From Ken Barber" This is a multi-part message in MIME format. ------=_NextPart_000_0007_01C149EA.EB67AE20 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hi, I purchased an old military 1000 watt dummy load at a hamfest today. = It is quite large and has industrial size radiators. I ran 500 watts = into it for about 5 minutes. I noticed that the input area where the = "N" connector is fastened got quite warm, whereas the rest of the dummy = load didn't seem to get warm at all. I opened it up and found that the = oil is low and would not completely cover up the resistive element and = that the oil is rather dirty. I saw in a radio handbook that = transformer oil may be obtained from the local power company, so I will = try them as a source. If you know of another source, please let me know = who it is. I know nothing about oil and heat transfer, so could someone explain = why one could not use motor oil or mineral oil or cooking oil such as = olive oil ? Secondly, should the transformer oil be filled right up to = the top of the dummy load or should there be a little room for = expansion? 73, Ken W2DTC ------=_NextPart_000_0007_01C149EA.EB67AE20 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Hi,

I purchased an = old military 1000 watt dummy load at a hamfest today. It = is=20 quite large and has industrial size radiators. I ran 500 = watts into=20 it for about 5 minutes. I noticed that the input area where = the "N"=20 connector is fastened got quite warm, whereas the rest of the dummy load = didn't=20 seem to get warm at all. I opened it up and found that the oil is = low and=20 would not completely cover up the resistive element and that the=20 oil is rather dirty. I saw in a radio handbook = that transformer oil=20 may be obtained from the local power company, so I will try them as = a=20 source. If you know of another source, please let me know who it=20 is.

I know nothing = about oil=20 and heat transfer, so could someone explain why one could not use motor = oil or=20 mineral oil or cooking oil such as olive oil ? Secondly, = should the=20 transformer oil be filled right up to the top of the dummy load or = should=20 there be a little room for expansion?

73,

Ken = W2DTC

------=_NextPart_000_0007_01C149EA.EB67AE20-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 1 01:51:55 2001 From: 2@vc.net (2) Date: Sun, 30 Sep 2001 17:51:55 -0700 Subject: [AMPS] transformer oil Message-ID: <200110010052.f910q9h12250@contesting.com> >Hi, > I purchased an old military 1000 watt dummy load at a hamfest today. It >is quite large and has industrial size radiators. I ran 500 watts into it >for about 5 minutes. I noticed that the input area where the "N" >connector is fastened got quite warm, whereas the rest of the dummy load >didn't seem to get warm at all. I opened it up and found that the oil is >low and would not completely cover up the resistive element and that the >oil is rather dirty. I saw in a radio handbook that transformer oil may >be obtained from the local power company, so I will try them as a source. >If you know of another source, please let me know who it is. > I know nothing about oil and heat transfer, so could someone explain why >one could not use motor oil or mineral oil or cooking oil such as olive >oil ? Secondly, should the transformer oil be filled right up to the top >of the dummy load or should there be a little room for expansion? // I use Mobil-1 five-wt. synthetic oil in my Bird dummy load. In that model, the oil lever should be just up to the filler hole with the load in the normal config. cheers, Ken - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From kc4slk@csrlink.net Mon Oct 1 02:05:43 2001 From: kc4slk@csrlink.net (Mike Sawyer) Date: Sun, 30 Sep 2001 21:05:43 -0400 Subject: Fw: [AMPS] transformer oil Message-ID: <005d01c14a15$32e01740$c17aadd1@kc4slk> This is a multi-part message in MIME format. ------=_NextPart_000_005A_01C149F3.AB282520 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable ----- Original Message -----=20 From: Mike Sawyer=20 To: Ken Barber=20 Sent: Sunday, September 30, 2001 8:50 PM Subject: Re: [AMPS] transformer oil Ken, First and foremost, the oil in the dummy load, may contain PCB's or = Poly-Chlorinated Biphenyl's. It is said to have been a carcinogen. That = having been said, generally dark oil means that it has been "cooked" = pretty good. Try to locate a silicone based oil. That is what they use = nowadays instead of the PCB type oil. If you can't locate it, mineral = oil will do well at a lower rating. If you can find an old Heath = 'Cantenna', it can give you an idea the difference between mineral oil = and transformer oil. I use the silicone based oil due to the fact that = it is available at work.=20 Gud luck, Mike(y) W3SLK ----- Original Message -----=20 From: Ken Barber=20 To: Radio-contesting.com=20 Sent: Sunday, September 30, 2001 8:03 PM Subject: [AMPS] transformer oil Hi, I purchased an old military 1000 watt dummy load at a hamfest today. = It is quite large and has industrial size radiators. I ran 500 watts = into it for about 5 minutes. I noticed that the input area where the = "N" connector is fastened got quite warm, whereas the rest of the dummy = load didn't seem to get warm at all. I opened it up and found that the = oil is low and would not completely cover up the resistive element and = that the oil is rather dirty. I saw in a radio handbook that = transformer oil may be obtained from the local power company, so I will = try them as a source. If you know of another source, please let me know = who it is. I know nothing about oil and heat transfer, so could someone explain = why one could not use motor oil or mineral oil or cooking oil such as = olive oil ? Secondly, should the transformer oil be filled right up to = the top of the dummy load or should there be a little room for = expansion? 73, Ken W2DTC ------=_NextPart_000_005A_01C149F3.AB282520 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

----- Original Message -----=20

From: Mike = Sawyer

To: Ken=20 Barber

Sent: Sunday, September 30, 2001 8:50 PM

Subject: Re: [AMPS] transformer oil

Ken,

First and foremost, the oil in the dummy load, = may=20 contain PCB's or Poly-Chlorinated Biphenyl's. It is said to have been a=20 carcinogen. That having been said, generally dark oil means that it has = been=20 "cooked" pretty good. Try to locate a silicone based oil. That is what = they use=20 nowadays instead of the PCB type oil. If you can't locate it, mineral = oil will=20 do well at a lower rating. If you can find an old Heath 'Cantenna', it = can give=20 you an idea the difference between mineral oil and transformer oil. I = use the=20 silicone based oil due to the fact that it is available at work.

Gud luck,

Mike(y)
W3SLK

----- Original Message -----
From:=20 Ken = Barber=20
To: Radio-contesting.com

Sent: Sunday, September 30, = 2001 8:03=20 PM

Subject: [AMPS] transformer = oil

Hi,

I purchased = an=20 old military 1000 watt dummy load at a hamfest today. = It is=20 quite large and has industrial size radiators. I ran 500 = watts into=20 it for about 5 minutes. I noticed that the input area where = the "N"=20 connector is fastened got quite warm, whereas the rest of the dummy = load=20 didn't seem to get warm at = all. I opened it up and found that the oil = is low and=20 would not completely cover up the resistive element and that the=20 oil is rather = dirty. I saw in a radio handbook = that transformer=20 oil may be obtained from the local power company, so I will try = them as a=20 source. If you know of another source, please let me know who it = is.

I know = nothing about oil=20 and heat transfer, so could someone explain why one could not use = motor oil or=20 mineral oil or cooking oil such as olive oil ? Secondly, = should the=20 transformer oil be filled right up to the top of the dummy = load or should=20 there be a little room for expansion?

73,

Ken = W2DTC

------=_NextPart_000_005A_01C149F3.AB282520-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Mike" Message-ID: <010c01c14a18$e23243a0$6401a8c0@neptune> This is a multi-part message in MIME format. ------=_NextPart_000_0109_01C149DE.35658EA0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Ken,=20 You can buy transformer oil from Ameritron or MFJ for $24.95/Gallon. = Transformer=20 oil has better thermal properties than mineral oil and thus will give = better power=20 handling than with mineral oil (MFJ gives derating curves for their = dummy load=20 using both transformer oil and mineral oil). Per the MFJ-250 manual, = motor oil is=20 not recommended for use in dummy loads due to its low vaporization = temperature. By the way, if you find a lower priced source for transformer oil, let = me know,=20 I need a couple more gallons for an upcoming project=20 73 de Mike, W4EF.......... =20 P.S. Since your dummy load is of unknown origin, you may want to = properly dispose of=20 the old oil as it might contain PCB's which are known to be carcinogenic = when burned. =20 ----- Original Message -----=20 From: Ken Barber=20 To: Radio-contesting.com=20 Sent: Sunday, September 30, 2001 5:03 PM Subject: [AMPS] transformer oil Hi, I purchased an old military 1000 watt dummy load at a hamfest today. = It is quite large and has industrial size radiators. I ran 500 watts = into it for about 5 minutes. I noticed that the input area where the = "N" connector is fastened got quite warm, whereas the rest of the dummy = load didn't seem to get warm at all. I opened it up and found that the = oil is low and would not completely cover up the resistive element and = that the oil is rather dirty. I saw in a radio handbook that = transformer oil may be obtained from the local power company, so I will = try them as a source. If you know of another source, please let me know = who it is. I know nothing about oil and heat transfer, so could someone explain = why one could not use motor oil or mineral oil or cooking oil such as = olive oil ? Secondly, should the transformer oil be filled right up to = the top of the dummy load or should there be a little room for = expansion? 73, Ken W2DTC =20 ------=_NextPart_000_0109_01C149DE.35658EA0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Ken,

You can buy transformer = oil from=20 Ameritron or MFJ for $24.95/Gallon. Transformer

oil has better thermal = properties than=20 mineral oil and thus will give better power

handling than with mineral oil = (MFJ gives=20 derating curves for their dummy load

using both transformer = oil and mineral oil). Per the MFJ-250 = manual, motor=20 oil is

not recommended for use in = dummy loads due to its low vaporization=20 temperature.

By the way, if you find a lower = priced=20 source for transformer oil, let me know,

I need a couple more gallons = for an=20 upcoming project

73 de Mike, = W4EF.......... =20

P.S. Since your dummy load is = of unknown=20 origin, you may want to properly dispose of

the old oil as it might contain PCB's which are known to be = carcinogenic when=20 burned.

----- Original Message -----

From:=20 Ken = Barber=20

To: Radio-contesting.com

Sent: Sunday, September 30, = 2001 5:03=20 PM

Subject: [AMPS] transformer = oil

Hi,

I purchased = an=20 old military 1000 watt dummy load at a hamfest today. = It is=20 quite large and has industrial size radiators. I ran 500 = watts into=20 it for about 5 minutes. I noticed that the input area where = the "N"=20 connector is fastened got quite warm, whereas the rest of the dummy = load=20 didn't seem to get warm at = all. I opened it up and found that the oil = is low and=20 would not completely cover up the resistive element and that the=20 oil is rather = dirty. I saw in a radio handbook = that transformer=20 oil may be obtained from the local power company, so I will try = them as a=20 source. If you know of another source, please let me know who it = is.

I know = nothing about oil=20 and heat transfer, so could someone explain why one could not use = motor oil or=20 mineral oil or cooking oil such as olive oil ? Secondly, = should the=20 transformer oil be filled right up to the top of the dummy = load or should=20 there be a little room for expansion?

73,

Ken = W2DTC

------=_NextPart_000_0109_01C149DE.35658EA0-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From K4SO@aol.com Mon Oct 1 02:46:24 2001 From: K4SO@aol.com (K4SO@aol.com) Date: Sun, 30 Sep 2001 21:46:24 EDT Subject: [AMPS] Noises in electrolytic capacitors Message-ID: <123.5255efc.28e924f0@aol.com> --part1_123.5255efc.28e924f0_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Tom gets the troubleshooting prize for this problem. After pulling the caps, I checked the equalizing/bleeder resistors and found one open! It looks absolutely perfect, no signs of physical damage such as heat, cracks or scrapes. I'll need to get a replacement, then see if the cap is damaged beyond use. It's doubtful at best. Thanks again for all the feedback. It's been an education beyond the initial problem. 73, Mark --part1_123.5255efc.28e924f0_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit Tom gets the troubleshooting prize for this problem. After pulling the caps, I checked the equalizing/bleeder resistors and found one open! It looks absolutely perfect, no signs of physical damage such as heat, cracks or scrapes. I'll need to get a replacement, then see if the cap is damaged beyond use. It's doubtful at best.

Thanks again for all the feedback. It's been an education beyond the initial problem.

73, Mark --part1_123.5255efc.28e924f0_boundary-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From wb8jkr@juno.com Mon Oct 1 10:16:04 2001 From: wb8jkr@juno.com (wb8jkr@juno.com) Date: Mon, 1 Oct 2001 05:16:04 -0400 Subject: [AMPS] transformer oil Message-ID: <20011001.052556.-945949.0.WB8JKR@juno.com> For what its worth, I did some research in this area about 10 years ago while building a large oil filled capacitor for a Tesla coil project. I found out that Texaco repackages "transformer oil" and sells it as "Turbine oil" its called Texaco R/O #46 and at that time it was about $20.00 for 5 gallons. 73, Mark WB8JKR Novice 3/71, General 8/72, Advanced 6/80, Extra 8/88 Member Society of Cable Telecommunication Engineers Member ARRL, DXCC, WAC, WAS, VUCC 2 meters, GJDXCC, OTC, RCC, QCWA On Sun, 30 Sep 2001 18:32:06 -0700 "Mike" writes: > Ken, > > You can buy transformer oil from Ameritron or MFJ for $24.95/Gallon. > Transformer > oil has better thermal properties than mineral oil and thus will > give better power > handling than with mineral oil (MFJ gives derating curves for their > dummy load > using both transformer oil and mineral oil). Per the MFJ-250 manual, > motor oil is > not recommended for use in dummy loads due to its low vaporization > temperature. > > By the way, if you find a lower priced source for transformer oil, > let me know, > I need a couple more gallons for an upcoming project > > 73 de Mike, W4EF.......... ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Mon Oct 1 15:40:34 2001 From: stevek@jmr.com (Steve Katz) Date: Mon, 1 Oct 2001 07:40:34 -0700 Subject: FW: [AMPS] 866A replacement .... SEMTECH STR4B32 ... any data ple ase Message-ID: > Walter, this is a 577 rectifier tube replacement, manufactured in the 24th > week of 1976, or now 25+ years old. > > Semtech hasn't made such items since the early 1980's. They are a local > company, here in Newbury Park, CA and I know their products well. Problem > with a lot of the old potted HV rectifier tube replacements is that they > are potted with Emerson-Cuming Stycast epoxy which, unless potted under a > vacuum, traps air bubbles that can invite corona. > > WB2WIK/6 > > "Each success only buys an admission ticket to a more difficult problem." > -- Henry Kissinger > > -----Original Message----- > From: Walter Dail [SMTP:kt4ja@cfl.rr.com] > Sent: Saturday, September 29, 2001 11:05 AM > To: amps@contesting.com > Subject: Re: [AMPS] 866A replacement .... SEMTECH STR4B32 ... any > data please > > > OK, while on the Semtech subject, I've got two Semtech STR 577, > with "7624" underneath that number(probably a lot number??) They are about > the same height as a 572B (maybe a little taller) with the four pins and > anode cap. > Does anyone have any data on these rectifier replacements? Ratings? I've > searched > the Semtech website with no luck. > > 73, > Walter - KT4JA > > ----- Original Message ----- > From: "skipp isaham" > To: > Sent: Saturday, September 29, 2001 12:54 PM > Subject: [AMPS] 866A replacement .... SEMTECH STR4B32 ... any data please > > > > > > - > > : From: "Wynand van Wyk" > > : Hi all, > > : I was today given two items at a flea market ... "you > > : are the only one I know that will appreciate and use > > : this in you amp projects" I was told. > > - > > At a flea market, it's most often the first indication that > > one should look for the attached anchor chain... > > - > > : It turns out to be two items with a 4 pin base (fits into > > : the 866A & 811A sockets) have hefty heat sinks and > > : anode cap on top. > > : About as tall as a 811A tube. > > : Markings ..SEMTECH STR4B32 > > : My guess it is a replacement solid state rectifier for > > : the 866A mercury valve rectifiers. > > - > > Not limited to the 866a replacement. There is a non > > mercury similar tube to the 866a which from memory > > is the 3B28 or 3B29.... one of those two numbers I > > believe. > > - > > Solid state replacements are/were very popular as a > > viable retrofit in tube power supplies. One must > > consider the original 866a has quite a bit of voltage > > drop while in operation. Same with the non merc > > tube (and most tube rectifiers). > > - > > It is interesting to know that some mfgrs often relied > > on the voltage drop as part of the circuit parameters. > > Replacement of the tube rectified raises the supply > > voltage, sometimes too high in certain circuits. There > > have been failures from the elevated supply voltages. > > - > > For a block of time, equipment owners were replacing > > vintage vacuum rectifiers with the ssr replacements. > > Most "get away" with the higher output supply voltage. > > They are made in all sizes and types, you happen to > > have a common HV SSR 4 pin unit. They are also > > manufactured for smaller supplies and popular in > > some Collins Amateur Equipment. > > - > > Some of us pull them back out of our amplifiers to > > restore vintage operation. In the tube guitar amplifier > > groups I frequent, we consider the "sag" (operating > > voltage drop) a feature. :-) They do offer a measure > > of ruggedness and reliability vs glass packages. I've > > never had one fail. There is a very slight increase in > > amplifier power. Extreme or marginal circuits might > > require adjustment of the zsac value. > > - > > I now run the non merc version in my 30-S1, the SSR > > units work and work in lower profile power supplies > > (which are viewed less often). Original 866a's > > still glow in circuits that allow their operational view > > from a safe position. The Viking Valiant is such an > > example. > > - > > I'll look to see if I have a data sheet for your particular > > ssr replacement. > > - > > : Any info and how I can utilize this in my High Voltage > > : supplies appreciated. > > : Wynand > > : ZS6ARF > > > > Most of the installation instructions are basic plug & > > play, but some are smart enough to advise caution > > related to the resultant elevated supply potential(s). > > - > > cheers > > skipp > > - > > > > ________________________________________________________________ > > GET INTERNET ACCESS FROM JUNO! > > Juno offers FREE or PREMIUM Internet access for less! > > Join Juno today! For your FREE software, visit: > > http://dl.www.juno.com/get/web/. > > > > -- > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > Submissions: amps@contesting.com > > Administrative requests: amps-REQUEST@contesting.com > > Problems: owner-amps@contesting.com > > > > > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jflanders2@home.com Mon Oct 1 20:51:33 2001 From: jflanders2@home.com (Jerry Flanders) Date: Mon, 01 Oct 2001 15:51:33 -0400 Subject: [AMPS] Special power-up on old unused AL-1200? Message-ID: <5.1.0.14.1.20011001154937.01e3cec0@mail> My 14 year old AL-1200 (w/internal QSK, bought new from Ameritron back then) has not been powered up for 6-8 years. I was about to power it up to get it working with my new IC-756PRO and it occurred to me that perhaps I need to take special care starting up the PS caps. I have a variac somewhere if I need to charge up slow but would rather not fool with any special precautions unless there is reason to. Any quickie advice before I plug it in? Thanks Jerry W4UK -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From oz1pif@get2net.dk Mon Oct 1 21:21:42 2001 From: oz1pif@get2net.dk (Peter Frenning, OZ1PIF) Date: Mon, 1 Oct 2001 22:21:42 +0200 Subject: [AMPS] Special power-up on old unused AL-1200? References: <5.1.0.14.1.20011001154937.01e3cec0@mail> Message-ID: <007701c14ab6$af5d11a0$0100a8be@oz1pif> Hi jerry, I would dust off the variac and slowly wind it up over 3-4 hours! Those caps need some reconditioning! Vy 73 de OZ1PIF, Peter New DXpedition to Greenland for CQWW! See: http://www.qsl.net/xp1ab ********** OZ1PIF ************** email: oz1pif(no-spam-filler)@get2net.dk http://hjem.get2net.dk/oz1pif Shack Ph. +45 4619 3208 Snailmail: Peter Frenning Ternevej 23 DK-4130 Viby Sj. Denmark *********************************** ----- Original Message ----- From: "Jerry Flanders" To: Sent: Monday, October 01, 2001 9:51 PM Subject: [AMPS] Special power-up on old unused AL-1200? > > My 14 year old AL-1200 (w/internal QSK, bought new from Ameritron back > then) has not been powered up for 6-8 years. I was about to power it up to > get it working with my new IC-756PRO and it occurred to me that perhaps I > need to take special care starting up the PS caps. I have a variac > somewhere if I need to charge up slow but would rather not fool with any > special precautions unless there is reason to. > > Any quickie advice before I plug it in? > > Thanks > > Jerry W4UK > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From kd4lyh@earthlink.net Tue Oct 2 00:00:13 2001 From: kd4lyh@earthlink.net (KD4LYH) Date: Mon, 1 Oct 2001 19:00:13 -0400 Subject: [AMPS] YC-156 Input impedance Message-ID: <000001c14acd$12cc1400$d3200b3f@computer> This is a multi-part message in MIME format. ------=_NextPart_000_000E_01C14AAB.4D3B9CE0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hello List , Could someone give me a ballpark figure as to the input impedance of a = yc-156. I would like to build a tuned input circuit.Is the input = impedance of the tube and the driving point impedance to different = things or are they the same. Any help is appreciated. Regards to All ------=_NextPart_000_000E_01C14AAB.4D3B9CE0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Hello List ,

Could someone give me a ballpark figure = as to the=20 input impedance of a yc-156. I would like to build a tuned input = circuit.Is the=20 input impedance of the tube and the driving point impedance to different = things=20 or are they the same. Any help is appreciated.

Regards to = All

------=_NextPart_000_000E_01C14AAB.4D3B9CE0-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From MWapner@Vetronix.com Mon Oct 1 22:07:52 2001 From: MWapner@Vetronix.com (Mike Wapner) Date: Mon, 1 Oct 2001 14:07:52 -0700 Subject: [AMPS] Henry 4K Ultra vs. 3K Classic X Mk II Message-ID: <11CA8AEBA4D7D0119FFF00805F29965D0287D8B0@EXCHANGE_NT1> Henry 4K Ultra (3CX1500A7) vs. Henry 3K Classic X MkII (3CX1200A7) > I have the opportunity to purchase one of these two amps. Any help with > the pros/cons of each would be appreciated. Thanks. Mike-K6QD -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From engelen.jan@skynet.be Mon Oct 1 23:21:34 2001 From: engelen.jan@skynet.be (engelen.jan) Date: Tue, 2 Oct 2001 00:21:34 +0200 Subject: [AMPS] Help with GS35B. Message-ID: This is a multi-part message in MIME format. ------=_NextPart_000_0048_01C14AD8.319934C0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit Hi, I�m building an amp with a gs35b using 2 designs : www.qsl.net/dl4mea & www.sci.fi/~oh3aww/pa_gu84b/eng/pa_gu84b.htm But because the output capacity�s of the 2 tubes are different, the length of the tube over the anode should be longer. BUT HOW MUCH LONGER?? That�s the problem� Can anyone help me with the calculation ? 73 ON1DSE Engelen Jan Mailto: Engelen.Jan@skynet.be Tel: + 32 495 232125 Barrierstraat 72 3960 Bree-B ------=_NextPart_000_0048_01C14AD8.319934C0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Hi,

I’m building an amp with a gs35b using 2 designs : =

www.qsl.net/dl4mea = & www.sci.fi/~= oh3aww/pa_gu84b/eng/pa_gu84b.htm <= /span>

But because the output capacity’s of the = 2 tubes are different, the length of the tube over the anode should be longer. BUT = HOW MUCH LONGER?? That’s the problem…=

Can anyone help me with the calculation ? =

73 ON1DSE

<= /p>

Engelen Jan = <= /b>

<= /b>

Mailto: = Engelen.Jan@skynet.be

Tel: + 32 495 232125<= /p>
Barrierstraat = 72<= /p>
3960 Bree-B<= /p>
<= /p>

------=_NextPart_000_0048_01C14AD8.319934C0-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Tue Oct 2 01:26:48 2001 From: W8JI@contesting.com (Tom Rauch) Date: Mon, 1 Oct 2001 20:26:48 -0400 Subject: [AMPS] Special power-up on old unused AL-1200? In-Reply-To: <5.1.0.14.1.20011001154937.01e3cec0@mail> Message-ID: <3BB8D188.21775.17E87C0F@localhost> > My 14 year old AL-1200 (w/internal QSK, bought new from Ameritron back > then) has not been powered up for 6-8 years. I was about to power it > up to get it working with my new IC-756PRO and it occurred to me that > perhaps I need to take special care starting up the PS caps. I have a > variac somewhere if I need to charge up slow but would rather not fool > with any special precautions unless there is reason to. Whatever you do, DON'T start it through a variac and wind it up slowly unless you defeat the step-start system!!!! While you can most likely just power it up (the capacitors have 550 volt foil and will handle extra leakage just fine for a while), if you want to be more comfortable you could disconnect the primarys and run one primary up slowly with a 120v variac. I think a bigger worry is the tube. I'd run the blower and the filament of the tube for three or four hours at full voltage before applying high voltage. You can do that with the primary of the HV transformer disconnected. Be careful messing with HV. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From kd4lyh@earthlink.net Tue Oct 2 03:16:34 2001 From: kd4lyh@earthlink.net (KD4LYH) Date: Mon, 1 Oct 2001 22:16:34 -0400 Subject: [AMPS] YC-156 Input Impedance Message-ID: <001601c14ae8$43a5ec20$e2200b3f@computer> This is a multi-part message in MIME format. ------=_NextPart_000_0013_01C14AC6.BAE16C00 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I would like to thank all the people who responded to my question. This is a great list. Best Regards Jeff KD4LYH ------=_NextPart_000_0013_01C14AC6.BAE16C00 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
I would like to thank all the people = who responded=20 to my question.

This is a great list.

Best Regards Jeff = KD4LYH
------=_NextPart_000_0013_01C14AC6.BAE16C00-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Tue Oct 2 03:22:58 2001 From: philk5pc@tyler.net (Phil Clements) Date: Mon, 1 Oct 2001 21:22:58 -0500 Subject: [AMPS] YC-156 Input impedance References: <000001c14acd$12cc1400$d3200b3f@computer> Message-ID: <016601c14ae9$278d6da0$a7084c42@phil> This is a multi-part message in MIME format. ------=_NextPart_000_0163_01C14ABF.3E066520 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable It is 25 ohms. The data on a 3CX15000B7 is where you look for Data on designing a linear amp. The YC-156 is the same tube, only with 5kw cooling fin. (((73))) Phil, K5PC Subject: [AMPS] YC-156 Input impedance Hello List , Could someone give me a ballpark figure as to the input impedance of a = yc-156. I would like to build a tuned input circuit.Is the input = impedance of the tube and the driving point impedance to different = things or are they the same. Any help is appreciated. Regards to All ------=_NextPart_000_0163_01C14ABF.3E066520 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
It is 25 = ohms.

The data on a = 3CX15000B7 is=20 where you look

for Data on = designing a=20 linear amp. The YC-156

is the same tube, = only with=20 5kw cooling fin.

(((73)))
Phil, = K5PC

Subject: [AMPS] YC-156 Input impedance

Hello List ,

Could someone give me a ballpark = figure as to the=20 input impedance of a yc-156. I would like to build a tuned input = circuit.Is=20 the input impedance of the tube and the driving point impedance to = different=20 things or are they the same. Any help is appreciated.

Regards to=20 All
------=_NextPart_000_0163_01C14ABF.3E066520-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From rabella@mail.ilstu.edu Tue Oct 2 03:06:42 2001 From: rabella@mail.ilstu.edu (Ralph A. Bellas) Date: Mon, 01 Oct 2001 21:06:42 -0500 Subject: [AMPS] Locate SB220 Resistors Message-ID: <3.0.3.32.20011001210642.0092c730@mail.ilstu.edu> I'm looking for a half dozen of the 4.7 M 2W resistors that are used in the SB220 metering circuit. Can anyone suggest a source for these? Thanks. Ralph K9ZO -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Tue Oct 2 04:57:30 2001 From: 2@vc.net (2) Date: Mon, 1 Oct 2001 20:57:30 -0700 Subject: [AMPS] Henry 4K Ultra vs. 3K Classic X Mk II Message-ID: <200110020357.f923vd303368@contesting.com> > >Henry 4K Ultra (3CX1500A7) vs. >Henry 3K Classic X MkII (3CX1200A7) >> I have the opportunity to purchase one of these two amps. Any help with >> the pros/cons of each would be appreciated. Thanks. Mike-K6QD > // The 3CX1200A7 has been obsoleted by the 3CX1200Z7. The ...A7 has much feedback C. Thus, it can become a VHF oscillator. The Z7 has about one-tenth as much feedback C, so it tends to be more stable. The 3CX1500A7/8877 also has little feedback C, however, one should probably use a low VHF-Q/VHF-Rp suppressor to minimize intermittent parasites. /see Figure 24 on my Web site/ >-- cheers, Mike - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Tue Oct 2 14:04:09 2001 From: 2@vc.net (2) Date: Tue, 2 Oct 2001 06:04:09 -0700 Subject: [AMPS] Noises in electrolytic capacitors Message-ID: <200110021304.f92D4H312715@contesting.com> >Tom gets the troubleshooting prize for this problem. // Agreed >After pulling the caps, >I checked the equalizing/bleeder resistors and found one open! It looks >absolutely perfect, no signs of physical damage such as heat, cracks or >scrapes. I'll need to get a replacement, then see if the cap is damaged >beyond use. It's doubtful at best. > >Thanks again for all the feedback. It's been an education beyond the initial >problem. > // Unreliability is why we do not proffer wire-wound resistors for electrolytic capacitor equalizer/bleeder service. Although lower value wire-wound resistors are fairly reliable, as you have apparently discovered, such is not the case with higher-value units. - My guess is that the capacitor that had the open bleeder has white deposits around the pressure vent. and/or shows higher leakage @450v. Replacing the entire string of capacitors with new, 105�C units might be best. I would also replace the wire-wound equalizer resistors with MOF resistors because they are more stable & more reliable. /sources: Mouser Electronics -- 800.346.6873. Digikey -- 800.344.4539/ cheers, Mark - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k7fm@teleport.com Tue Oct 2 14:36:26 2001 From: k7fm@teleport.com (Lamb) Date: Tue, 2 Oct 2001 06:36:26 -0700 Subject: [AMPS] Noises in electrolytic capacitors References: <200110021304.f92D4H312715@contesting.com> Message-ID: <009c01c14b47$40773540$e43c1ad8@colinlam> In aircraft, a dual ignition system is used - because your life depends upon it. Perhaps a good practice to adopt is to use a redundancy on the bleeder resistors. This would protect the capacitors from blowing and also make sure the voltage is discharged. A suggestion would be to either have one set as the main bleeder/equalizer set with a high value in parallel as a backup, or have parallel resistors of twice the value. I like wire would resistors with a low enough resistance to load the power supply. Because of their fragility (my spell checker seems to like that word), a high value metal film resistor could be used in parallel. An annual glance at the discharge rate on the voltage meter would tell you if the primary resistors are still intact. And since our memories are failing, we can document the decay time in the manual under "notes and modifications" that we religiously keep. 73, Colin K7FM -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k1xt@hotmail.com Tue Oct 2 14:55:51 2001 From: k1xt@hotmail.com (bill thomas) Date: Tue, 02 Oct 2001 08:55:51 -0500 Subject: [AMPS] Henry 4K Ultra vs. 3K Classic X Mk II Message-ID: >From: Mike Wapner >To: "'amps@contesting.com'" >Subject: [AMPS] Henry 4K Ultra vs. 3K Classic X Mk II >Date: Mon, 1 Oct 2001 14:07:52 -0700 > > >Henry 4K Ultra (3CX1500A7) vs. >Henry 3K Classic X MkII (3CX1200A7) > > I have the opportunity to purchase one of these two amps. Any help with > > the pros/cons of each would be appreciated. Thanks. Mike-K6QD > > I have a Henry 3K Classic X with a 3cx1500a7 and it has worked flawlessly for me. Thirty-five to forty watts in gives me 1500 out. It's much easier to find 3cx1500a7 tubes on the second market as well as pullouts. They are a very prolific tube. Don't mess with the suppresor. There is no need to. Bill k1xt _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From phil@vaxxine.com Tue Oct 2 15:02:04 2001 From: phil@vaxxine.com (Phil (VA3UX)) Date: Tue, 02 Oct 2001 10:02:04 -0400 Subject: [AMPS] Noises in electrolytic capacitors In-Reply-To: <200110021304.f92D4H312715@contesting.com> Message-ID: <5.0.2.1.0.20011002095801.009f3ec0@vaxxine.com> At 06:04 AM 10/2/2001 -0700, 2 wrote: > >Tom gets the troubleshooting prize for this problem. > >// Agreed > > >After pulling the caps, > >I checked the equalizing/bleeder resistors and found one open! It looks > >absolutely perfect, no signs of physical damage such as heat, cracks or > >scrapes. I'll need to get a replacement, then see if the cap is damaged > >beyond use. It's doubtful at best. Thinking back a number of years, I had exactly the same experience with the equalizers in my Viewstar amp. Two of them were open, with absolutely no visual evidence that anything was wrong. These were 10 watt Ohmite Brown Devils - decent quality wirewounds by most standards. The resistors "looked" like new. In my case, the capacitors were fine despite the open resistors. Phil > > > >Thanks again for all the feedback. It's been an education beyond the > initial > >problem. > > >// Unreliability is why we do not proffer wire-wound resistors for >electrolytic capacitor equalizer/bleeder service. Although lower value >wire-wound resistors are fairly reliable, as you have apparently >discovered, such is not the case with higher-value units. >- My guess is that the capacitor that had the open bleeder has white >deposits around the pressure vent. and/or shows higher leakage @450v. >Replacing the entire string of capacitors with new, 105�C units might be >best. I would also replace the wire-wound equalizer resistors with MOF >resistors because they are more stable & more reliable. /sources: >Mouser Electronics -- 800.346.6873. Digikey -- 800.344.4539/ > >cheers, Mark > >- R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. >end > > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Tue Oct 2 15:32:00 2001 From: stevek@jmr.com (Steve Katz) Date: Tue, 2 Oct 2001 07:32:00 -0700 Subject: [AMPS] Henry 4K Ultra vs. 3K Classic X Mk II Message-ID: Mike, unless Henry has come back out with the 4K Ultra, that's a rather old design that's "continuous tune" from 3.5 through 30 MHz and offers excellent coverage of frequencies between the ham bands, so used to be popular with government agencies, embassies, etc. It had some neat features like a filament voltage adjustment and test points, not normally found on amateur equipment. It's a good amp, but does not cover 160m and requires the typical "8877 three minute warm-up," which can be frustrating (for me). I just sold a 3K Premier (which is a 3K Classic X Mk III, virtually no difference with the Mk II) which had 160m coverage. I don't recall if the "Mark II" covers 160 or not, maybe not. The Mk III definitely does, as does the "Premier," whatever that means. This was obviously a rather huge cost adder, as Henry used large B&W coil stock (not a toroid) to add 160m, as well as lots of HV doorknob padders switched in by their famous plunger switches driven by the bandswitch which also drives a chain, pulleys, triple-action camshaft (only kidding) and all that stuff that makes the bandswitch difficult to turn. I might have had a parasite problem with the 3K Premier, never investigated fully enough to ascertain; however I used to use the amp quite a lot on the lower bands (160, 80, 40) and one day noted a large change in the way it tuned on 40. Still made 1500W output, but tuned in a different point, leading me to believe something failed. Sure enough, investigation revealed two doorknob caps had cracked in half, leaving pieces of ceramic material laying around inside the RF cage, and with that, their values had obviously changed (or possibly dropped to zero). These were 7500V caps -- Henry doesn't really skrimp on components. The parasitic suppressor on the 3CX1200D7 still looked fine, although I didn't isolate the resistor from the inductor to measure the R. But something made those doorknobs blow. On the bright side, if you live in the L.A. area, as long as Henry's in business, they'll service those amps and probably have spare parts for them. I've found their service to be rather remarkable. I brought in an old 3K Classic X (export model) which was 12 years old and long out of warranty and whose roller inductor had jammed the roller between turns of the inductor (having jumped off the track) and burned the plate RF Choke; they not only repaired it for free, but upgraded it to current production standards, also for free. They do take responsibility when something fails due to poor design. 73, Mike. Steve WB2WIK/6 > Henry 4K Ultra (3CX1500A7) vs. > Henry 3K Classic X MkII (3CX1200A7) > > I have the opportunity to purchase one of these two amps. Any help with > > the pros/cons of each would be appreciated. Thanks. Mike-K6QD > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Ken Barber" This is a multi-part message in MIME format. ------=_NextPart_000_0009_01C14B43.BB985820 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable First of all thanks to the many who replied, I got a lot of good = information. I learned a lot and I appreciate it, you guys are really = great. My power company is so large and so protected that I was unable = to make contact with anyone who know anything. The maintenance = department referred me to the transportation department etc...... The suggestion to buy 5 weight mobil-1 was interesting but nowhere = could I locate this weight oil. Someone (many thanks to you!) steered me to MFJ who sells this oil = and that is my solution to my problem. I just placed my order. Again thanks, 73, Ken W2DTC --------------------------------------------------- Hi, I purchased an old military 1000 watt dummy load at a hamfest today. = It is quite large and has industrial size radiators. I ran 500 watts = into it for about 5 minutes. I noticed that the input area where the = "N" connector is fastened got quite warm, whereas the rest of the dummy = load didn't seem to get warm at all. I opened it up and found that the = oil is low and would not completely cover up the resistive element and = that the oil is rather dirty. I saw in a radio handbook that = transformer oil may be obtained from the local power company, so I will = try them as a source. If you know of another source, please let me know = who it is. I know nothing about oil and heat transfer, so could someone explain = why one could not use motor oil or mineral oil or cooking oil such as = olive oil ? Secondly, should the transformer oil be filled right up to = the top of the dummy load or should there be a little room for = expansion? 73, Ken W2DTC ------=_NextPart_000_0009_01C14B43.BB985820 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

   First of all=20 thanks to the many who replied, I got a lot of good information. I = learned a=20 lot and I appreciate it, you guys are really great. My = power=20 company is so large and so protected that I was unable to make = contact with=20 anyone who know anything. The maintenance department referred me to = the=20 transportation department etc......

   The = suggestion=20 to buy 5 weight mobil-1 was interesting but nowhere could I = locate=20 this weight oil.

   Someone (many thanks to you!) = steered=20 me to MFJ who sells this oil and that is my solution to my = problem. I just=20 placed my order.

Again thanks,

73,

   Ken W2DTC

---------------------------------------------------

Hi,

I purchased an = old military 1000 watt dummy load at a hamfest today. It = is=20 quite large and has industrial size radiators. I ran 500 = watts into=20 it for about 5 minutes. I noticed that the input area where = the "N"=20 connector is fastened got quite warm, whereas the rest of the dummy load = didn't=20 seem to get warm at all.  I opened it up and found that the oil is = low and=20 would not completely cover up the resistive element and that the=20 oil is rather dirty.  I saw in a radio handbook = that transformer oil=20 may be obtained from the local power company, so I will try them as = a=20 source. If you know of another source, please let me know who it=20 is.

I know nothing = about oil=20 and heat transfer, so could someone explain why one could not use motor = oil or=20 mineral oil or cooking oil such as olive oil ?  Secondly, = should the=20 transformer oil be filled right up to the top of the dummy load or = should=20 there be a little room for expansion?

73,

Ken = W2DTC

= ------=_NextPart_000_0009_01C14B43.BB985820-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From pringle50@home.com Tue Oct 2 21:37:29 2001 From: pringle50@home.com (pringle50@home.com) Date: Tue, 2 Oct 2001 15:37:29 -0500 Subject: [AMPS] transformer oil revisited Message-ID: <002701c14b82$1554df80$c4620e41@htsbrg1.ms.home.com> BlankW2DTC I'm sure you are relieved to find transformer oil for your dummy load. Some hams use mineral oil but frankly its not comparable. There use to be several manufacturers of transformer oil but I'm not for sure that all still do it. The ones I use to purchase when I managed a large transformer manufacturing facility was Sun Oil in Pennsylvania where W3HNK, the worlds best QSL Manager worked for many years and from Shell Oil in Martinez, CA. The oil was shipped in a tanker rail car and would typically take 10-14 days to reach us. During the transit time, the transformer oil would absorb moisture and the net effect would be that the dielectric strength would be greatly reduced, necessitating processing prior to including in a transformer. This process involves pumping the oil into a large pressure vessel that is under high vacuum conditions and heating up the oil while in this state. Gasses would be liberated and the moisture removed, thus increasing the dielectric strength. Ideally this oil should be capable of 45,000 volts but it was not uncommon to see it arrive at a dielectric strength of 20,000 volts. My point is that depending on where you live, particularly if you live in a real humid environment, your oil will absorb moisture so you will need to replace it and in my case on my own dummy load here in Mississippi, once per year. Within a transformer, the oil served two main purposes. One as a heat transfer agent and one as an insulator. Within your dummy load it does exactly the same thing. You CAN NOT seal the dummy load because as you heat the load immersed in the oil, gases are expelled and must be vented through a relief valve on your dummy load. Transformer oil is very difficult to set on fire but once you do it is very difficult to extinguish so keep this in mind and be very careful to not overheat. Don't know what you paid for the transformer oil but it would not surprise me that it was in the range of $18-24/gallon as it was costing over $2.00/gallon in the 70's when I purchased it for our transformer manufacturing plant. That price would be in line compared to other price escalation in aluminum, steel copper etc. I'm a retired electrical engineer and no longer involved in manufacturing but thought you may be interested in these comments. 73, J. Leon Pringle, Jr W 5 N A E-Mail: w5na@megagate.com or w5na@mdxa.org or pringle50@home.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From wd7s@att.net Tue Oct 2 20:22:30 2001 From: wd7s@att.net (PAUL HEWITT) Date: Tue, 2 Oct 2001 14:22:30 -0500 Subject: [AMPS] YC-156 Input impedance In-Reply-To: <016601c14ae9$278d6da0$a7084c42@phil> Message-ID: I am very curious how you arrived at that input impedance. As you know EVERY set of operating parameters results in a different drive impedance and the original question did not supply any operating information. Are you guessing? Or worse yet are you reading from a data sheet under typical operation? I'm sure that nowhere on the 3cx15000b7 data sheet is there any information, (except the constant current curves), for operating this tube at the reduced power level(I hope) the builder plans to use. Paul PAUL HEWITT WD7S PRODUCTIONS QRO HOMEBREW COMPONENTS http://wd7s.home.att.net -----Original Message----- From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On Behalf Of Phil Clements Sent: Monday, October 01, 2001 9:23 PM To: KD4LYH; amps@contesting.com Subject: Re: [AMPS] YC-156 Input impedance It is 25 ohms. The data on a 3CX15000B7 is where you look for Data on designing a linear amp. The YC-156 is the same tube, only with 5kw cooling fin. (((73))) Phil, K5PC Subject: [AMPS] YC-156 Input impedance Hello List , Could someone give me a ballpark figure as to the input impedance of a yc-156. I would like to build a tuned input circuit.Is the input impedance of the tube and the driving point impedance to different things or are they the same. Any help is appreciated. Regards to All -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Ken Barber" This is a multi-part message in MIME format. ------=_NextPart_000_0040_01C14B79.EDEC58E0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Lee, Had I not had found MFJ as a source for the transformer oil I sure = would have written a letter. It was indeed a hassle, first the insane push = button routine, then the "your call is important to us" garbage, then the referrals to hell and back. As a retired guy, I want to keep hassles to a minimum. When I was working, hassles were a daily occurrence and my system was hardened to hassles, now that I have plenty of time to actually pursue the "hassle system" I find it more relaxing to just write a check and be done with = it. 73 and thanks for your interest, Ken W2DTC ---------------------------------------------------- ----- Original Message ----- From: "LEE R. WICAL" To: "Ken Barber" Sent: Tuesday, October 02, 2001 3:29 PM Subject: Ken de Lee > Ken: > I'd Write a letter to the power company president with your simple request. > Quite getting jerked around, by jerks who are passing the buck. > I would write! > Lee > > At 01:11 PM 10/2/01 -0400, you wrote: > > The maintenance department referred me to the = transportation > >department etc...... oil. I just placed my order. Again > >thanks, 73, Ken W2DTC > >--------------------------------------------------- Hi, > >If you know of another source, please let me know who it is. or should > > there be a little room for expansion? 73, Ken W2DTC ------=_NextPart_000_0040_01C14B79.EDEC58E0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Lee,
   Had I not had found MFJ as a source for the=20 transformer oil I sure would
have written a letter. It was = indeed a=20 hassle, first the insane push button
routine, then the "your = call is=20 important to us" garbage, then the
referrals to hell and=20 back.
   As a retired guy, I want to keep hassles to a=20 minimum. When I was
working, hassles were a daily occurrence = and my=20 system was hardened to
hassles, now that I have plenty of time to = actually=20 pursue the "hassle
system" I find it more relaxing to just write a = check and=20 be done with it.
73 and thanks for your interest,
Ken=20 W2DTC
----------------------------------------------------

= -----=20 Original Message -----
From: "LEE R. WICAL" <leewical@lava.net>
To: "Ken = Barber"=20 <kenw2dtc@home.com>
Sent:=20 Tuesday, October 02, 2001 3:29 PM
Subject: Ken de Lee

> = Ken:
> I'd Write a letter to the power company president with your = simple
request.
> Quite getting jerked around, by jerks who are = passing=20 the buck.
> I would write!
> Lee
>
> At 01:11 PM = 10/2/01=20 -0400, you wrote:
>=20 >            = The=20 maintenance department referred me to the transportation
>=20 >department etc......       =20 oil.      I just placed my order. = Again
>=20 >thanks,   73,    Ken W2DTC
>=20 >--------------------------------------------------- Hi,
> = >If you=20 know of another source, please let me know who it =20 is.     or
should
> > there be a little = room for=20 expansion? 73, Ken W2DTC
------=_NextPart_000_0040_01C14B79.EDEC58E0-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w2cqm@juno.com Wed Oct 3 02:14:43 2001 From: w2cqm@juno.com (Ronald Lumachi) Date: Tue, 2 Oct 2001 21:14:43 -0400 Subject: [AMPS] SELL: 6m deck components Message-ID: <20011002.212830.6830.2.W2CQM@juno.com> SELL: A 6m component package consisting of the following: Reduced output Eimac 8877 tested at 1000W output (70%) 1983 date code. Clean, no dents or discolorations. Shipped in original carton. Grid and idle current perfect. Includes a Johnson 8877 air system socket w/grid to ground tabs, HV plate choke for 6m, heavy wall teflon chimney, 180 second 110VAC solid state delay timer, two (2) 12VDC@10W zener diodes and the 6m tank coil. $225+ shipping for the entire package. Ron W2CQM/3 -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 3 03:46:23 2001 From: 2@vc.net (2) Date: Tue, 2 Oct 2001 19:46:23 -0700 Subject: [AMPS] Noises in electrolytic capacitors Message-ID: <200110030246.f932kUZ12132@contesting.com> > >In aircraft, a dual ignition system is used - because your life depends upon >it. Perhaps a good practice to adopt is to use a redundancy on the bleeder >resistors. This would protect the capacitors from blowing and also make >sure the voltage is discharged. > // Two equalizers in parallel would not solve the open-resistor problem because the resistance across each capacitor must be the same at all times or capacitor failure is certain. High value wire-wound resistors have a higher failure rate than MOF resistors, so the solution is avoid wire-wound resistors in this application. >... ... - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 3 03:46:27 2001 From: 2@vc.net (2) Date: Tue, 2 Oct 2001 19:46:27 -0700 Subject: [AMPS] Noises in electrolytic capacitors Message-ID: <200110030246.f932kYZ12141@contesting.com> > >At 06:04 AM 10/2/2001 -0700, 2 wrote: > >> >Tom gets the troubleshooting prize for this problem. >> >>// Agreed >> >> >After pulling the caps, >> >I checked the equalizing/bleeder resistors and found one open! It looks >> >absolutely perfect, no signs of physical damage such as heat, cracks or >> >scrapes. I'll need to get a replacement, then see if the cap is damaged >> >beyond use. It's doubtful at best. > > >Thinking back a number of years, I had exactly the same experience with the >equalizers in my Viewstar amp. Two of them were open, with absolutely no >visual evidence that anything was wrong. These were 10 watt Ohmite Brown >Devils // An apt name. >- decent quality wirewounds by most standards. The resistors >"looked" like new. In my case, the capacitors were fine despite the open >resistors. > // If this situation had gone on for long, two of the filter capacitors would have been long gone. cheers, Phil > >> > >> >Thanks again for all the feedback. It's been an education beyond the >> initial >> >problem. >> > >>// Unreliability is why we do not proffer wire-wound resistors for >>electrolytic capacitor equalizer/bleeder service. Although lower value >>wire-wound resistors are fairly reliable, as you have apparently >>discovered, such is not the case with higher-value units. >>- My guess is that the capacitor that had the open bleeder has white >>deposits around the pressure vent. and/or shows higher leakage @450v. >>Replacing the entire string of capacitors with new, 105�C units might be >>best. I would also replace the wire-wound equalizer resistors with MOF >>resistors because they are more stable & more reliable. /sources: >>Mouser Electronics -- 800.346.6873. Digikey -- 800.344.4539/ >> >>cheers, Mark >> >>- R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. >>end >> >> >>-- >>FAQ on WWW: http://www.contesting.com/FAQ/amps >>Submissions: amps@contesting.com >>Administrative requests: amps-REQUEST@contesting.com >>Problems: owner-amps@contesting.com > > > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 3 03:46:29 2001 From: 2@vc.net (2) Date: Tue, 2 Oct 2001 19:46:29 -0700 Subject: [AMPS] Henry 4K Ultra vs. 3K Classic X Mk II Message-ID: <200110030246.f932kaZ12147@contesting.com> > >Mike, unless Henry has come back out with the 4K Ultra, that's a rather old >design that's "continuous tune" from 3.5 through 30 MHz and offers excellent >coverage of frequencies between the ham bands, so used to be popular with >government agencies, embassies, etc. It had some neat features like a >filament voltage adjustment and test points, // Excellent idea. Some Collins amplifiers had this feature. >not normally found on amateur >equipment. It's a good amp, but does not cover 160m and requires the >typical "8877 three minute warm-up," which can be frustrating (for me). > // Amen >I just sold a 3K Premier (which is a 3K Classic X Mk III, virtually no >difference with the Mk II) which had 160m coverage. I don't recall if the >"Mark II" covers 160 or not, maybe not. The Mk III definitely does, as does >the "Premier," whatever that means. This was obviously a rather huge cost >adder, as Henry used large B&W coil stock (not a toroid) to add 160m, as >well as lots of HV doorknob padders switched in by their famous plunger >switches driven by the bandswitch which also drives a chain, pulleys, >triple-action camshaft (only kidding) and all that stuff that makes the >bandswitch difficult to turn. > >I might have had a parasite problem with the 3K Premier, never investigated >fully enough to ascertain; however I used to use the amp quite a lot on the >lower bands (160, 80, 40) and one day noted a large change in the way it >tuned on 40. Still made 1500W output, but tuned in a different point, >leading me to believe something failed. Sure enough, investigation revealed >two doorknob caps had cracked in half, leaving pieces of ceramic material >laying around inside the RF cage, and with that, their values had obviously >changed (or possibly dropped to zero). These were 7500V caps // What were the C values? tnx >-- Henry >doesn't really skrimp on components. // Henry Radio resonant-choke power supplies are formidable. >The parasitic suppressor on the >3CX1200D7 still looked fine, although I didn't isolate the resistor from the >inductor to measure the R. But something made those doorknobs blow. > // My guess is that it probably wasn't a parasite. > ... cheerz > > >> Henry 4K Ultra (3CX1500A7) vs. >> Henry 3K Classic X MkII (3CX1200A7) >> > I have the opportunity to purchase one of these two amps. Any help with >> > the pros/cons of each would be appreciated. Thanks. Mike-K6QD >> >> >> -- >> FAQ on WWW: http://www.contesting.com/FAQ/amps >> Submissions: amps@contesting.com >> Administrative requests: amps-REQUEST@contesting.com >> Problems: owner-amps@contesting.com > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Wed Oct 3 06:42:20 2001 From: philk5pc@tyler.net (Phil Clements) Date: Wed, 3 Oct 2001 00:42:20 -0500 Subject: [AMPS] YC-156 Input impedance References: Message-ID: <01d701c14bce$2cdb4bc0$a7084c42@phil> Phil Clements 410 VZ CR 4903 Ben Wheeler, TX 75754 ----- Original Message ----- From: "PAUL HEWITT" To: "Phil Clements" ; "KD4LYH" ; Sent: Tuesday, October 02, 2001 2:22 PM Subject: RE: [AMPS] YC-156 Input impedance > I am very curious how you arrived at > that input impedance. As you know EVERY > set of operating parameters results in a > different drive impedance and the > original question did not supply any > operating information. Are you > guessing? Or worse yet are you reading > from a data sheet under typical > operation? I'm sure that nowhere on the > 3cx15000b7 data sheet is there any > information, (except the constant > current curves), for operating this tube > at the reduced power level(I hope) the > builder plans to use. > Paul Wrong, Kimo-Sabe! The Eimac data sheet plainly states that typical performance (measured data) to 30 mhz that the cathode input impedance is 24 ohms. It also states that a resonant input circuit should be installed at the cathode, and it is to have a Q of 5 or MORE. This assumes an anode RL of 1000 ohms. For folks that would go to all the trouble and expense to put one of these tubes and then operate it at reduced output, a few bucks more will buy you a tuned input circuit with a roller coil and two variable caps. People might wonder why anyone would use a YC-156. Pulls are beginning to show up at reasonable prices from the usual MRI repair sources. They require no socket, they bolt right to the chassis. The 6 kv supply that is powering a 4-1000A amp is just perfect for the YC-156. And last but not least, it should last a lifetime loafing at 1500 watts. On my YC-156,I use my usual choice of input circuit. I buy them from Henry radio, all pre-wired and pre mounted; 160-10 meters. They are 50 ohms in and 50 ohms out. I then go through a 2:1 transformer (an old Alpha 77SX trick) to arrive at 25 ohms with a Q of 5+. I told the man 25 ohms because that will get him in the ball park starting out. We have a lot of headroom here...what's a few DB with a 15 DB gain bottle? Been there, done that, got the "T" shirt. (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Wed Oct 3 12:47:00 2001 From: W8JI@contesting.com (Tom Rauch) Date: Wed, 3 Oct 2001 07:47:00 -0400 Subject: [AMPS] YC-156 Input impedance In-Reply-To: <01d701c14bce$2cdb4bc0$a7084c42@phil> Message-ID: <3BBAC274.24188.1F7DE15E@localhost> > Wrong, Kimo-Sabe! > The Eimac data sheet plainly states that typical performance > (measured data) to 30 mhz that the cathode input impedance > is 24 ohms. It also states that a resonant input circuit should be > installed at the cathode, and it is to have a Q of 5 or MORE. This > assumes an anode RL of 1000 ohms. Using Eimac's characteristic curves in a software generated Chafffe analysis all for class AB2: 6000v @ 14000w=30 ohms cathode impedance 6500v @ 12000w=23 ohms 5000v @ 10,000w=19 ohms Driving impedance depends greatly on operating conditions. Most 3CPX5000's I have seen are around 18-20 ohms. > For folks that would go to all the trouble and expense to put > one of these tubes and then operate it at reduced output, a > few bucks more will buy you a tuned input circuit with a roller > coil and two variable caps. While impedance matching can be accomplished many ways, the most important improvement of using a tuned input is realized when the tuned input proveds a very low impedance at the cathode for harmonics of the operating frequency, especially the low-order harmonics. That means where ever and how ever the tuned input is located, impedance measurements from the cathode looking back at that network should show a virtual short at harmonics of the operating frequency. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Wed Oct 3 13:23:19 2001 From: W8JI@contesting.com (Tom Rauch) Date: Wed, 3 Oct 2001 08:23:19 -0400 Subject: [AMPS] Noises in electrolytic capacitors In-Reply-To: <5.0.2.1.0.20011002095801.009f3ec0@vaxxine.com> References: <200110021304.f92D4H312715@contesting.com> Message-ID: <3BBACAF7.18989.1F9F223B@localhost> > Thinking back a number of years, I had exactly the same experience > with the equalizers in my Viewstar amp. Two of them were open, with > absolutely no visual evidence that anything was wrong. While I have no idea specifically about the resistor used in that case, when looking at the parts inherited from other "XXXXstar" bankruptcy purchases many were surplus. Amp supply had the same purchase mentality. I remember all the HV 1 megohm meter multiplier resistors purchased from Electronic Surplus in Cleveland, and how often they failed despite being operated under their ratings. Obviously those resistors were there because someone dumped them. The problem with that is some parts are on the surplus market because they are rejects, and unreliable. Surplus parts are never a bargain, because you can usually buy the parts new and with some assurance they are OK for less money. Bleeder and equalizing resistors should be high-rel parts. They should NEVER be carbon or carbon film, and they should be 100% tested. Wire wound parts are actually just as reliable as film or oxide resistors, if you get good parts. Carbon resistors are a huge problem, and should never be used. The same goes for resistors that rivet or crimp resistance wire to a terminal. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Wed Oct 3 13:23:19 2001 From: W8JI@contesting.com (Tom Rauch) Date: Wed, 3 Oct 2001 08:23:19 -0400 Subject: [AMPS] Noises in electrolytic capacitors In-Reply-To: <009c01c14b47$40773540$e43c1ad8@colinlam> Message-ID: <3BBACAF7.25126.1F9F2196@localhost> > A suggestion would be to either have one set as the main > bleeder/equalizer set with a high value in parallel as a backup, or > have parallel resistors of twice the value. In the case of equal value parallel resistors, the capacitors would have to be rated at twice the normal operating voltage. Otherwise you gain nothing. Using a high value and low value in parallel would really be wasteful. If the resistors serve the purpose of bleeders only, and not equalization, then two systems in parallel is a worthwhile idea...except for the following condition:. anyone who depends on bleeders to guarantee no HV after a given period of time is a fool, and we should let Darwin's selective evolution theory go to work and cull him out of the gene pool. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Wt8r@aol.com Wed Oct 3 13:47:58 2001 From: Wt8r@aol.com (Wt8r@aol.com) Date: Wed, 3 Oct 2001 08:47:58 EDT Subject: [AMPS] Problem with AL-811H Message-ID: --part1_c8.1b76777b.28ec62fe_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit I am attempting to repair an AL-811H for a friend. The amp has been abused due to mishandling as aircraft baggage making several trips to the Caribbean and back. The outer case shows several dings and one of the threaded holes in the chassis metal which holds the cover in place has been broken open. The reported symptoms are: When attempting to tune the amp upon return to home QTH, there was a pop and a flash inside the amp. On my bench, I am driving the amp using an Icom 751-A. The only visible signs of damage evident to any of the electronic components was one of the two 1000pF DC blocking capacitors from the anode/plate RFC to the tank circuit was cracked open slightly. I replaced these with two 500pF (6KV) capacitors for test purposes with no apparent difference in result. Using an ohm meter, it appears that the DC input blocking capacitors at the top end of the filament RF choke are good and that no short circuit to ground exists on the input. The tubes show no internal shorts using an ohm meter. The tubes light properly, the HV is 1700V and the anode idling current when keyed (without drive) is 150 mA (which is about right). I disassembled the rear pc board from the rear panel and inspected the traces for burns and shorts, but nothing was obvious. When attempting to operate the amp, the grid current and plate current swing up and down in synchronism with the drive, but NO RF output is observed. I am using a power meter and a Bird 2500 watt dummy load. Adjustment of the TUNE and LOAD capacitor produce no apparent dip nor power output. No unusual smell or noise is observed. Any suggestions would be greatly appreciated. Dave, WT8R --part1_c8.1b76777b.28ec62fe_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit I am attempting to repair an AL-811H for a friend. The amp has been abused due to mishandling as aircraft baggage making several trips to the Caribbean and back. The outer case shows several dings and one of the threaded holes in the chassis metal which holds the cover in place has been broken open.

The reported symptoms are: When attempting to tune the amp upon return to home QTH, there was a pop and a flash inside the amp.

On my bench, I am driving the amp using an Icom 751-A. The only visible signs of damage evident to any of the electronic components was one of the two 1000pF DC blocking capacitors from the anode/plate RFC to the tank circuit was cracked open slightly. I replaced these with two 500pF (6KV) capacitors for test purposes with no apparent difference in result. Using an ohm meter, it appears that the DC input blocking capacitors at the top end of the filament RF choke are good and that no short circuit to ground exists on the input. The tubes show no internal shorts using an ohm meter. The tubes light properly, the HV is 1700V and the anode idling current when keyed (without drive) is 150 mA (which is about right).

I disassembled the rear pc board from the rear panel and inspected the traces for burns and shorts, but nothing was obvious.

When attempting to operate the amp, the grid current and plate current swing up and down in synchronism with the drive, but NO RF output is observed. I am using a power meter and a Bird 2500 watt dummy load. Adjustment of the TUNE and LOAD capacitor produce no apparent dip nor power output. No unusual smell or noise is observed.

Any suggestions would be greatly appreciated.

Dave, WT8R

--part1_c8.1b76777b.28ec62fe_boundary-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From bjk@ihug.co.nz Wed Oct 3 14:03:42 2001 From: bjk@ihug.co.nz (Barry Kirkwood) Date: Thu, 4 Oct 2001 01:03:42 +1200 Subject: [AMPS] Noises in electrolytic capacitors References: <200110021304.f92D4H312715@contesting.com> <3BBACAF7.18989.1F9F223B@localhost> Message-ID: <03cf01c14c0b$d7a12ce0$30d0adcb@ihug.co.nz> Very Interesting! My Viewstar had the same problem. Ended out building new capacitor mounts as exact replacements not available here. Used new German hi spec resistors. No problems since. 73 end Barry Kirkwood PhD ZL1DD Signal Hill Homestay 66 Cory Road Palm Beach Waiheke Island 1240 NEW ZEALAND www.waiheke.co.nz/signal.htm ----- Original Message ----- From: Tom Rauch To: ; Phil (VA3UX) Cc: Sent: Thursday, 04 October, 2001 12:23 AM Subject: Re: [AMPS] Noises in electrolytic capacitors > > > > Thinking back a number of years, I had exactly the same experience > > with the equalizers in my Viewstar amp. Two of them were open, with > > absolutely no visual evidence that anything was wrong. > > While I have no idea specifically about the resistor used in that > case, when looking at the parts inherited from other "XXXXstar" > bankruptcy purchases many were surplus. > > Amp supply had the same purchase mentality. I remember all the > HV 1 megohm meter multiplier resistors purchased from Electronic > Surplus in Cleveland, and how often they failed despite being > operated under their ratings. Obviously those resistors were there > because someone dumped them. > > The problem with that is some parts are on the surplus market > because they are rejects, and unreliable. Surplus parts are never a > bargain, because you can usually buy the parts new and with > some assurance they are OK for less money. > > Bleeder and equalizing resistors should be high-rel parts. They > should NEVER be carbon or carbon film, and they should be 100% > tested. Wire wound parts are actually just as reliable as film or > oxide resistors, if you get good parts. > > Carbon resistors are a huge problem, and should never be used. > The same goes for resistors that rivet or crimp resistance wire to a > terminal. > 73, Tom W8JI > W8JI@contesting.com > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jkolin@worldnet.att.net Wed Oct 3 05:04:02 2001 From: jkolin@worldnet.att.net (J Kolin) Date: Wed, 3 Oct 2001 00:04:02 -0400 Subject: [AMPS] SB-220 Message-ID: <000401c14bc0$735a8240$02000003@ne2q> I have an SB-220 UNBUILT kit in the original two cartons. Complete. What is this thing worth these days? Jay NE2Q -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From K4SO@aol.com Wed Oct 3 14:21:39 2001 From: K4SO@aol.com (K4SO@aol.com) Date: Wed, 3 Oct 2001 09:21:39 EDT Subject: [AMPS] Noises in electrolytic capacitors Message-ID: --part1_a2.1a5a50ea.28ec6ae3_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit For whatever it's worth, the part in question is labeled HEI 8732, FST-20. I have ordered an Ohmite 25W unit with the same physical characteristics. While we all hope for 100% reliability, these parts lasted 13 years (of admittedly intermittent use) before 1 failed. Luckily the failure was not catastrophic. I have never trusted them to protect me from HV, I always watch the meter, then short the HV before diving in. The idea of redundancy is generally a good one, but it doesn't sound like there is a viable option for that here. I even thought about pulling the whole mess and throwing in an overrated oil filled cap and a BIG bleeder, but I've got spares and I'm gambling that this repair, with new caps, should hold up for a while. Thanks again. 73, Mark --part1_a2.1a5a50ea.28ec6ae3_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit For whatever it's worth, the part in question is labeled HEI 8732, FST-20. I have ordered an Ohmite 25W unit with the same physical characteristics. While we all hope for 100% reliability, these parts lasted 13 years (of admittedly intermittent use) before 1 failed. Luckily the failure was not catastrophic. I have never trusted them to protect me from HV, I always watch the meter, then short the HV before diving in.

The idea of redundancy is generally a good one, but it doesn't sound like there is a viable option for that here. I even thought about pulling the whole mess and throwing in an overrated oil filled cap and a BIG bleeder, but I've got spares and I'm gambling that this repair, with new caps, should hold up for a while.

Thanks again.

73, Mark --part1_a2.1a5a50ea.28ec6ae3_boundary-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jtml@lanl.gov Wed Oct 3 14:59:21 2001 From: jtml@lanl.gov (John T. M. Lyles) Date: Wed, 3 Oct 2001 07:59:21 -0600 Subject: [AMPS] Xfmr Oil In-Reply-To: <200110030345.f933jbZ13692@contesting.com> References: <200110030345.f933jbZ13692@contesting.com> Message-ID: We use many gallons per year of Shell Diala X Transformer Oil. It is widely available from Shell jobbers, and comes in 55 gallon drums. There are much more expensive silicone based oils called Envirotemp or something like that, but they aren't recommended except in extreme cases. As W5NA said, to get the full dielectric strength of this oil, as it would be required for a 4160:13,800 V transformer, it must be processed, heated, filled with vacuum on top, then a nitrogen blanket added at the end to prevent oxidation products from forming and eleminate most moisture ingress. We use Diala up to 90 kVDC in some modulators for klystrons. For 1 kW Dummy Loads, it would be fine to use without all the precautions. It is made esp for electrical gear and can handle occasional arcs, although this is detremental to oils in general (and equipment). S D Meyers Company (headquartered in Ohio, but having district offices all over the US) does a lot of powerline transfomer rebuilding and oil processing, and may sell you small quantities if you call them. We have a contract where a semi-truck mounted hot oil processing system comes every year. They recirculate our transformer oils through Fullers Earth (a clay) and other filtration. Also checking the chemistry for various gases which indicate overheating and arcing. In this way, we have extended the lifetime of some 2 MVA transformers beyond 30 years without failure. 73 John K5PRO -- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w9wis@charter.net Wed Oct 3 15:07:54 2001 From: w9wis@charter.net (Michael Melland) Date: Wed, 03 Oct 2001 09:07:54 -0500 Subject: [AMPS] Xfmr Oil In-Reply-To: Message-ID: > We use many gallons per year of Shell Diala X Transformer Oil. Last year I had picked up a used Bird RF load and wanted to replace the resistor core inside as it was slightly out of specs. As long as I was doing this I wanted to replace the oil.... Bird only stocks replacement transformer oil in 5 gal pails and it was sort of expensive. Eventually the tech I dealt with at Bird sent me the material data sheets for the oil they use.... Shell Diala X. I couldn't find a source locally that would sell me any in under a 5 gal pail..... I phoned the maintenance department of our local power provider and the supervisor told me I could stop in a they'd provide me with some. I ended up receiving 2 gallons pumped right from their bulk tank and they gave it to me free. They said they purchase it by rail tanker and the time to process my .20 of oil would cost way more then what the oil would cost. Rebuilt the load and all is fine..... and I have quite a bit of x-former oil to spare. I had asked about storage of the oil and they said just to keep my containers sealed and it would store indefinitely. I ended up getting a very nice tour of the shop and watched them rebuild some large transformers..... pretty neat. Mike, W9WIS -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Wed Oct 3 15:22:56 2001 From: stevek@jmr.com (Steve Katz) Date: Wed, 3 Oct 2001 07:22:56 -0700 Subject: [AMPS] Henry 4K Ultra vs. 3K Classic X Mk II Message-ID: > > > >Mike, unless Henry has come back out with the 4K Ultra, that's a rather > old > >design that's "continuous tune" from 3.5 through 30 MHz and offers > excellent > >coverage of frequencies between the ham bands, so used to be popular with > >government agencies, embassies, etc. It had some neat features like a > >filament voltage adjustment and test points, > > // Excellent idea. Some Collins amplifiers had this feature. > > >not normally found on amateur > >equipment. It's a good amp, but does not cover 160m and requires the > >typical "8877 three minute warm-up," which can be frustrating (for me). > > > // Amen > > >I just sold a 3K Premier (which is a 3K Classic X Mk III, virtually no > >difference with the Mk II) which had 160m coverage. I don't recall if > the > >"Mark II" covers 160 or not, maybe not. The Mk III definitely does, as > does > >the "Premier," whatever that means. This was obviously a rather huge > cost > >adder, as Henry used large B&W coil stock (not a toroid) to add 160m, as > >well as lots of HV doorknob padders switched in by their famous plunger > >switches driven by the bandswitch which also drives a chain, pulleys, > >triple-action camshaft (only kidding) and all that stuff that makes the > >bandswitch difficult to turn. > > > >I might have had a parasite problem with the 3K Premier, never > investigated > >fully enough to ascertain; however I used to use the amp quite a lot on > the > >lower bands (160, 80, 40) and one day noted a large change in the way it > >tuned on 40. Still made 1500W output, but tuned in a different point, > >leading me to believe something failed. Sure enough, investigation > revealed > >two doorknob caps had cracked in half, leaving pieces of ceramic material > >laying around inside the RF cage, and with that, their values had > obviously > >changed (or possibly dropped to zero). These were 7500V caps > > // What were the C values? > > ::I don't recall, but in the 100-300pF range, I believe (plate tuning pi > input padders) > > >-- Henry > >doesn't really skrimp on components. > > // Henry Radio resonant-choke power supplies are formidable. > > >The parasitic suppressor on the > >3CX1200D7 still looked fine, although I didn't isolate the resistor from > the > >inductor to measure the R. But something made those doorknobs blow. > > > // My guess is that it probably wasn't a parasite. > ::Maybe not, I never found out. The funny thing about the pi-L circuits > used by Henry in most of their amps is that they will resonate with many > combinations of C and L, and since everything is fully adjustable > (including the L), one can achieve 1500W output with lots of tuning > combinations. There is only one "most correct" combination, that results > in max output with minimum input power (and also minimum grid current), > and it can take some time to find that point. Then, changing antennas > creates the need to go through the hunt once again... > > > ... > > cheerz > > > > > >> Henry 4K Ultra (3CX1500A7) vs. > >> Henry 3K Classic X MkII (3CX1200A7) > >> > I have the opportunity to purchase one of these two amps. Any help > with > >> > the pros/cons of each would be appreciated. Thanks. Mike-K6QD > >> > >> > >> -- > >> FAQ on WWW: http://www.contesting.com/FAQ/amps > >> Submissions: amps@contesting.com > >> Administrative requests: amps-REQUEST@contesting.com > >> Problems: owner-amps@contesting.com > > > >-- > >FAQ on WWW: http://www.contesting.com/FAQ/amps > >Submissions: amps@contesting.com > >Administrative requests: amps-REQUEST@contesting.com > >Problems: owner-amps@contesting.com > > > > > > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. > end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Wed Oct 3 15:34:51 2001 From: stevek@jmr.com (Steve Katz) Date: Wed, 3 Oct 2001 07:34:51 -0700 Subject: [AMPS] Problem with AL-811H Message-ID: > I am attempting to repair an AL-811H for a friend. The amp has been > abused due to mishandling as aircraft baggage making several trips to the > Caribbean and back. The outer case shows several dings and one of the > threaded holes in the chassis metal which holds the cover in place has > been broken open. > > The reported symptoms are: When attempting to tune the amp upon return to > home QTH, there was a pop and a flash inside the amp. > > ::Sounds like someone took a picture. Did you pose? > > On my bench, I am driving the amp using an Icom 751-A. The only visible > signs of damage evident to any of the electronic components was one of the > two 1000pF DC blocking capacitors from the anode/plate RFC to the tank > circuit was cracked open slightly. I replaced these with two 500pF (6KV) > capacitors for test purposes with no apparent difference in result. Using > an ohm meter, it appears that the DC input blocking capacitors at the top > end of the filament RF choke are good and that no short circuit to ground > exists on the input. The tubes show no internal shorts using an ohm > meter. The tubes light properly, the HV is 1700V and the anode idling > current when keyed (without drive) is 150 mA (which is about right). > > I disassembled the rear pc board from the rear panel and inspected the > traces for burns and shorts, but nothing was obvious. > > When attempting to operate the amp, the grid current and plate current > swing up and down in synchronism with the drive, but NO RF output is > observed. I am using a power meter and a Bird 2500 watt dummy load. > Adjustment of the TUNE and LOAD capacitor produce no apparent dip nor > power output. No unusual smell or noise is observed. > > ::This really sounds like a T-R relay not making contact, or possibly not > even switching. I don't recall if the AL811H has a separate input relay > and output relay, or if they're all one unit; however, the symptoms seem > to indicate an open circuit between the plate tank and the coaxial output > receptacle... > > Any suggestions would be greatly appreciated. > > Dave, WT8R > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Wed Oct 3 15:35:47 2001 From: stevek@jmr.com (Steve Katz) Date: Wed, 3 Oct 2001 07:35:47 -0700 Subject: [AMPS] SB-220 Message-ID: Wow, I'll bet that's worth quite a bit to a bona fide Heath collector! To the rest of us, it's just an old pair of 3-500Z's and a pile of parts... > I have an SB-220 UNBUILT kit in the original two cartons. Complete. What > is > this thing worth these days? > > Jay NE2Q > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w2ge@home.com Wed Oct 3 16:21:23 2001 From: w2ge@home.com (Phil Levin W2GE) Date: Wed, 3 Oct 2001 11:21:23 -0400 Subject: [AMPS] SB-220 In-Reply-To: <000401c14bc0$735a8240$02000003@ne2q> Message-ID: Would you believe maybe 2000 or more??? With eBay these days anything is possible. Unbuilt Heathkits are like gold.... Phil W2GE -----Original Message----- From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On Behalf Of J Kolin Sent: Wednesday, October 03, 2001 12:04 AM To: amps@contesting.com Subject: [AMPS] SB-220 I have an SB-220 UNBUILT kit in the original two cartons. Complete. What is this thing worth these days? Jay NE2Q -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From wb8jkr@juno.com Wed Oct 3 16:33:44 2001 From: wb8jkr@juno.com (wb8jkr@juno.com) Date: Wed, 3 Oct 2001 11:33:44 -0400 Subject: [AMPS] SB-220 Message-ID: <20011003.113548.-944441.2.WB8JKR@juno.com> On Ebay you should get 3 grand !! ;^( I wouldn't give more than $600.00 but its just my opinion. Mark WB8JKR On Wed, 3 Oct 2001 00:04:02 -0400 "J Kolin" writes: > > I have an SB-220 UNBUILT kit in the original two cartons. Complete. > What is > this thing worth these days? > > Jay NE2Q > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 3 16:51:36 2001 From: 2@vc.net (2) Date: Wed, 3 Oct 2001 08:51:36 -0700 Subject: [AMPS] SB-220 Message-ID: <200110031551.f93FpfZ28017@contesting.com> > >Wow, I'll bet that's worth quite a bit to a bona fide Heath collector! To >the rest of us, it's just an old pair of 3-500Z's and a pile of parts... > // On e.bay,com one sold for a seemingly celestial price. cheers > >> I have an SB-220 UNBUILT kit in the original two cartons. Complete. What >> is >> this thing worth these days? >> >> Jay NE2Q >> >> >> -- >> FAQ on WWW: http://www.contesting.com/FAQ/amps >> Submissions: amps@contesting.com >> Administrative requests: amps-REQUEST@contesting.com >> Problems: owner-amps@contesting.com > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 3 16:51:37 2001 From: 2@vc.net (2) Date: Wed, 3 Oct 2001 08:51:37 -0700 Subject: [AMPS] Noises in electrolytic capacitors Message-ID: <200110031551.f93FphZ28023@contesting.com> > >> A suggestion would be to either have one set as the main >> bleeder/equalizer set with a high value in parallel as a backup, or >> have parallel resistors of twice the value. > >In the case of equal value parallel resistors, the capacitors would >have to be rated at twice the normal operating voltage. > >Otherwise you gain nothing. > >Using a high value and low value in parallel would really be >wasteful. > >If the resistors serve the purpose of bleeders only, and not >equalization, then two systems in parallel is a worthwhile >idea...except for the following condition:. > >anyone who depends on bleeders to guarantee no HV after a given >period of time is a fool, and we should let Darwin's selective >evolution theory go to work and cull him out of the gene pool. > // The amount of energy stored (<100J) would be unlikely to cause death. I know of no one eho became a Silent Key because of an open bleeder resistor in a ham amp. All such decedents that I am aware of didn't pull the mains plug. cheers - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Wed Oct 3 16:59:28 2001 From: stevek@jmr.com (Steve Katz) Date: Wed, 3 Oct 2001 08:59:28 -0700 Subject: [AMPS] SB-220 Message-ID: Hard to believe anyone would pay $2K for having to do at least two weekends' worth of work and end up with an amplifier that is beneath the overall quality and performance of, say, an AL-82 that costs $2195 retail, assembled and with a warranty. But I suppose there are some....what did P.T. Barnum say, again? "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: wb8jkr@juno.com [SMTP:wb8jkr@juno.com] > Sent: Wednesday, October 03, 2001 8:34 AM > To: jkolin@worldnet.att.net > Cc: amps@contesting.com > Subject: Re: [AMPS] SB-220 > > > On Ebay you should get 3 grand !! ;^( > > I wouldn't give more than $600.00 but its > just my opinion. > > Mark WB8JKR > > > On Wed, 3 Oct 2001 00:04:02 -0400 "J Kolin" > writes: > > > > I have an SB-220 UNBUILT kit in the original two cartons. Complete. > > What is > > this thing worth these days? > > > > Jay NE2Q > > > > > > -- > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > Submissions: amps@contesting.com > > Administrative requests: amps-REQUEST@contesting.com > > Problems: owner-amps@contesting.com > > > > ________________________________________________________________ > GET INTERNET ACCESS FROM JUNO! > Juno offers FREE or PREMIUM Internet access for less! > Join Juno today! For your FREE software, visit: > http://dl.www.juno.com/get/web/. > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From gdaught6@leland.stanford.edu Wed Oct 3 17:32:59 2001 From: gdaught6@leland.stanford.edu (George T. Daughters) Date: Wed, 3 Oct 2001 09:32:59 -0700 Subject: [AMPS] Re: Darwinian selection: was : Noises in electrolytic capacitors In-Reply-To: <200110031551.f93FphZ28023@contesting.com> Message-ID: <200110031633.f93GX0V11760@smtp1.Stanford.EDU> Hi, Tom, then Rich wrote... > >anyone who depends on bleeders to guarantee no HV after a given > >period of time is a fool, and we should let Darwin's selective > >evolution theory go to work and cull him out of the gene pool. > > > // The amount of energy stored (<100J) would be unlikely to cause > death. > I know of no one eho became a Silent Key because of an open bleeder > resistor in a ham amp. All such decedents that I am aware of didn't > pull the mains plug. 100 Joules, ill-timed with respect to the heart's intrinsic excitation and unfortunately applied such that the right (or wrong, actually) amount goes through the heart, is plenty to kill. What usually happens though, is a big-a** "kick" as most of the skeletal muscles get stimulated, and we are launched from our previous position. The safe way is: 1) pull the mains, 2) short the HV and 3) use the one-hand-in-the-pocket method. People who leave the mains plugged in are prime Darwinian candidates, partly because even a "little" shock can make you jump and your hand(s) can go where you didn't intend them... like the AC line, or HV AC. I had a shop-teacher Elmer (not a ham)who taught me "Every tool you own is waiting to make you bleed." I've adapted that to "Every electronic/electrical circuit is waiting to make you dead." 73, George Daughters, K6GT See you in the 2001 CQP! (California QSO Party, October 6-7) -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From rrossi@btv.ibm.com Wed Oct 3 17:57:18 2001 From: rrossi@btv.ibm.com (Ron D. Rossi) Date: Wed, 03 Oct 2001 12:57:18 -0400 Subject: [AMPS] Re: Darwinian selection: was : Noises in electrolytic capacitors In-Reply-To: <200110031633.f93GX0V11760@smtp1.Stanford.EDU> Message-ID: <200110031657.MAA28316@johnpaul.btv.ibm.com> >>>"George T. Daughters" said: > > 100 Joules, ill-timed with respect to the heart's intrinsic > excitation and unfortunately applied such that the right (or wrong, > actually) amount goes through the heart, is plenty to kill. What > usually happens though, is a big-a** "kick" as most of the skeletal > muscles get stimulated, and we are launched from our previous > position. And as a reference... prehospital defibrillation protocols call for 200J, then 300J, then all subsequent shocks at 360J! -- 73 es God Bless de KK1L...ron (kk1l@arrl.net) <>< QTH: Jericho, Vermont My page: http://www.qsl.net/kk1l -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Wed Oct 3 18:11:38 2001 From: philk5pc@tyler.net (Phil Clements) Date: Wed, 3 Oct 2001 12:11:38 -0500 Subject: [AMPS] YC-156 Input impedance References: Message-ID: <021901c14c2e$77ba7700$a7084c42@phil> ----- Original Message ----- From: "PAUL HEWITT" To: "Phil Clements" Sent: Wednesday, October 03, 2001 9:04 AM Subject: RE: [AMPS] YC-156 Input impedance > It's too bad your engineering skills > don't match your ability at being a > smart-ass. Been there-did it wrong is > probably more accurate. > > PAUL HEWITT > WD7S PRODUCTIONS > QRO HOMEBREW COMPONENTS The response to your post to me and the reflector was tailored you your terse and pithy remarks. It is very sad that you have no sense of humor, and hate to be proven wrong. I gave the guy good advice, and backed up by Tom Rauch's calculations, and my actual operating conditions with a working YC-156 here on the desk. The guy has not asked for more details, so I assume my advice was helpful to him. Most folks who know me will tell you that my engineering skills DO match my ability at being a smart-ass. I have been there (first home-brew amp in 1954) and been "doing it" ever since. I try to give people honest advice here on the reflector, tailored to the question asked. I try to refrain from telling how to build a watch when asked what time it is. (((73))) Phil, K5PC > Subject: Re: [AMPS] YC-156 Input impedance > Sent: Tuesday, October 02, 2001 2:22 PM > > I am very curious how you arrived at > > that input impedance. As you know > EVERY > > set of operating parameters results in > a > > different drive impedance and the > > original question did not supply any > > operating information. Are you > > guessing? Or worse yet are you > reading > > from a data sheet under typical > > operation? I'm sure that nowhere on > the > > 3cx15000b7 data sheet is there any > > information, (except the constant > > current curves), for operating this > tube > > at the reduced power level(I hope) the > > builder plans to use. > > Paul > > Wrong, Kimo-Sabe! > The Eimac data sheet plainly states that > typical performance > (measured data) to 30 mhz that the > cathode input impedance > is 24 ohms. It also states that a > resonant input circuit should be > installed at the cathode, and it is to > have a Q of 5 or MORE. > This assumes an anode RL of 1000 ohms. > > For folks that would go to all the > trouble and expense to put > one of these tubes and then operate it > at reduced output, a > few bucks more will buy you a tuned > input circuit with a roller > coil and two variable caps. > > People might wonder why anyone would use > a YC-156. > Pulls are beginning to show up at > reasonable prices from > the usual MRI repair sources. They > require no socket, they > bolt right to the chassis. The 6 kv > supply that is powering a > 4-1000A amp is just perfect for the > YC-156. And last but not > least, it should last a lifetime loafing > at 1500 watts. > > On my YC-156,I use my usual choice of > input circuit. I buy > them from Henry radio, all pre-wired and > pre mounted; 160-10 > meters. They are 50 ohms in and 50 ohms > out. I then go through > a 2:1 transformer (an old Alpha 77SX > trick) to arrive at 25 ohms > with a Q of 5+. > > I told the man 25 ohms because that will > get him in the ball park > starting out. We have a lot of headroom > here...what's a few DB > with a 15 DB gain bottle? > > Been there, done that, got the "T" > shirt. > > (((73))) > Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Wed Oct 3 18:16:09 2001 From: philk5pc@tyler.net (Phil Clements) Date: Wed, 3 Oct 2001 12:16:09 -0500 Subject: [AMPS] YC-156 Input impedance References: Message-ID: <022301c14c2f$1907ccc0$a7084c42@phil> > With fixed tuned input networks, > "ballpark" figures are of no use. > Thanks, Paul > > PAUL HEWITT > WD7S PRODUCTIONS > QRO HOMEBREW COMPONENTS Fixed tuned inputs with a Q of 5 or better are hard to come up with if one wishes to cover an entire band. (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From doug@nc.rr.com Wed Oct 3 18:57:24 2001 From: doug@nc.rr.com (Doug Hall) Date: Wed, 3 Oct 2001 13:57:24 -0400 Subject: [AMPS] SB-220 In-Reply-To: Message-ID: I can't tell from your comment whether you're serious or not. Surely you must know that the vast majority of people who buy unbuilt Heathkits have no intention of ever building them. And even though you can't believe it, there are quite a number of folks who would take considerable delight in owning a little bit of amateur radio history in the form of an unbuilt Heathkit SB-220. As far as price is concerned, the laws of supply and demand still apply - why shouldn't they? Doug, K4DSP > -----Original Message----- > From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On > Behalf Of Steve Katz > Sent: Wednesday, October 03, 2001 11:59 AM > To: 'wb8jkr@juno.com'; jkolin@worldnet.att.net > Cc: amps@contesting.com > Subject: RE: [AMPS] SB-220 > > > > Hard to believe anyone would pay $2K for having to do at least > two weekends' > worth of work and end up with an amplifier that is beneath the overall > quality and performance of, say, an AL-82 that costs $2195 > retail, assembled > and with a warranty. But I suppose there are some....what did P.T. Barnum > say, again? -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Wed Oct 3 18:55:03 2001 From: stevek@jmr.com (Steve Katz) Date: Wed, 3 Oct 2001 10:55:03 -0700 Subject: [AMPS] SB-220 Message-ID: Hi Doug, Unfortunately, I was serious. But then, I've never been a "collector" of anything. My enjoyment in ham radio is actually using the equipment and making contacts with it. I know there are others who enjoy other aspects... 73, Steve, WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Doug Hall [SMTP:doug@nc.rr.com] > Sent: Wednesday, October 03, 2001 10:57 AM > To: Steve Katz > Cc: amps@contesting.com > Subject: RE: [AMPS] SB-220 > > > I can't tell from your comment whether you're serious or not. Surely you > must know that the vast majority of people who buy unbuilt Heathkits have > no > intention of ever building them. > > And even though you can't believe it, there are quite a number of folks > who > would take considerable delight in owning a little bit of amateur radio > history in the form of an unbuilt Heathkit SB-220. As far as price is > concerned, the laws of supply and demand still apply - why shouldn't they? > > Doug, K4DSP > > > -----Original Message----- > > From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On > > Behalf Of Steve Katz > > Sent: Wednesday, October 03, 2001 11:59 AM > > To: 'wb8jkr@juno.com'; jkolin@worldnet.att.net > > Cc: amps@contesting.com > > Subject: RE: [AMPS] SB-220 > > > > > > > > Hard to believe anyone would pay $2K for having to do at least > > two weekends' > > worth of work and end up with an amplifier that is beneath the overall > > quality and performance of, say, an AL-82 that costs $2195 > > retail, assembled > > and with a warranty. But I suppose there are some....what did P.T. > Barnum > > say, again? -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From wd7s@att.net Wed Oct 3 15:04:12 2001 From: wd7s@att.net (PAUL HEWITT) Date: Wed, 3 Oct 2001 09:04:12 -0500 Subject: [AMPS] YC-156 Input impedance In-Reply-To: <3BBAC274.24188.1F7DE15E@localhost> Message-ID: PAUL HEWITT WD7S PRODUCTIONS QRO HOMEBREW COMPONENTS http://wd7s.home.att.net > Wrong, Kimo-Sabe! > The Eimac data sheet plainly states that typical performance > (measured data) to 30 mhz that the cathode input impedance > is 24 ohms. It also states that a resonant input circuit should be > installed at the cathode, and it is to have a Q of 5 or MORE. This > assumes an anode RL of 1000 ohms. Using Eimac's characteristic curves in a software generated Chafffe analysis all for class AB2: 6000v @ 14000w=30 ohms cathode impedance 6500v @ 12000w=23 ohms 5000v @ 10,000w=19 ohms Driving impedance depends greatly on operating conditions. I think I said this Most 3CPX5000's I have seen are around 18-20 ohms. > For folks that would go to all the trouble and expense to put > one of these tubes and then operate it at reduced output, a > few bucks more will buy you a tuned input circuit with a roller > coil and two variable caps. While impedance matching can be accomplished many ways, the most important improvement of using a tuned input is realized when the tuned input proveds a very low impedance at the cathode for harmonics of the operating frequency, especially the low-order harmonics. That means where ever and how ever the tuned input is located, impedance measurements from the cathode looking back at that network should show a virtual short at harmonics of the operating frequency. 73, Tom W8JI W8JI@contesting.com Do you know what values were used to establish the load line used in your Chaffe analysis? With fixed tuned input networks, "ballpark" figures are of no use. Thanks, Paul PAUL HEWITT WD7S PRODUCTIONS QRO HOMEBREW COMPONENTS http://wd7s.home.att.net -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 3 20:42:20 2001 From: 2@vc.net (2) Date: Wed, 3 Oct 2001 12:42:20 -0700 Subject: [AMPS] Re: Darwinian selection: was : Noises in electrolytic capacitors Message-ID: <200110031942.f93JgPZ04480@contesting.com> > > >Hi, > >Tom, then Rich wrote... > > >> >anyone who depends on bleeders to guarantee no HV after a given >> >period of time is a fool, and we should let Darwin's selective >> >evolution theory go to work and cull him out of the gene pool. >> > >> // The amount of energy stored (<100J) would be unlikely to cause >> death. >> I know of no one eho became a Silent Key because of an open bleeder >> resistor in a ham amp. All such decedents that I am aware of didn't >> pull the mains plug. > >100 Joules, ill-timed with respect to the heart's intrinsic >excitation and unfortunately applied such that the right (or wrong, >actually) amount goes through the heart, is plenty to kill. // Defibrillators have more than 100 Joules. >What usually happens though, is a big-a** "kick" as most of the skeletal >muscles get stimulated, and we are launched from our previous >position. > >The safe way is: 1) pull the mains, // Amen, George > 2) short the HV // In a G-G amplifier, if some remaining charge is on the filter capacitor, shorting the HV to gnd is a fairly reliable way to zap the grid current meter. My shorting stick has a 1000-ohm, 100W resistor in series with it to limit peak discharge current. . >3) and use the >one-hand-in-the-pocket method. > // Especially after a 6-pack of 811s. >People who leave the mains plugged in are prime Darwinian candidates, >partly because even a "little" shock can make you jump and your >hand(s) can go where you didn't intend them... like the AC line, or >HV AC. > >I had a shop-teacher Elmer (not a ham)who taught me "Every tool you >own is waiting to make you bleed." I've adapted that to "Every >electronic/electrical circuit is waiting to make you dead." > >73, > > >George Daughters, K6GT - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Wed Oct 3 20:46:21 2001 From: philk5pc@tyler.net (Phil Clements) Date: Wed, 3 Oct 2001 14:46:21 -0500 Subject: [AMPS] SB-220 References: Message-ID: <026a01c14c44$14690ac0$a7084c42@phil> > I can't tell from your comment whether you're serious or not. Surely you > must know that the vast majority of people who buy unbuilt Heathkits have no > intention of ever building them. They don't even want the box to be opened! The minute construction is begun, the price drops about $2 grand on a 220. E-Bay never ceases to amaze me....Collins, Drake, and un-built Heaths bring unbelievable prices. (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Wed Oct 3 21:03:55 2001 From: W8JI@contesting.com (Tom Rauch) Date: Wed, 3 Oct 2001 16:03:55 -0400 Subject: [AMPS] YC-156 Input impedance In-Reply-To: <022301c14c2f$1907ccc0$a7084c42@phil> Message-ID: <3BBB36EB.3217.2144E13C@localhost> > Fixed tuned inputs with a Q of 5 or better are hard to > come up with if one wishes to cover an entire band. 80 and 160 are the worse bands in terms of BW. Using a network Q of 5 and 18 ohms load R, 50 ohms source R... I get 5380 pF/1.84uH/ 8157 pF for 160-meters and an SWR of 1.5:1 at band edges. That's about 10% BW at 1.5:1 VSWR using normal component Q's and a network Q of 5. (network Q is higher than the simple Q Handbooks often use). So you should be able to do 370 kHz on 80, 700 kHz on 40, 1.4 MHz BW on 20. Most likely you actually don't need that much Q anyway, you just have to be sure the second and higher harmonics see a low impedance and the network matches the load and source. Eimac's data are just general suggestions and results vary with the actual operating conditions and circuit. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Wed Oct 3 21:03:55 2001 From: W8JI@contesting.com (Tom Rauch) Date: Wed, 3 Oct 2001 16:03:55 -0400 Subject: [AMPS] YC-156 Input impedance In-Reply-To: References: <3BBAC274.24188.1F7DE15E@localhost> Message-ID: <3BBB36EB.3788.2144E257@localhost> > Do you know what values were used to > establish the load line used in your > Chaffe analysis? yes. > With fixed tuned input networks, > "ballpark" figures are of no use. They certainly are. You have to start somewhere. Anyone who thinks he can do a paper design or look at a operating sheet and not tweak anything is living in dream-land. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From carlseye@tampabay.rr.com Wed Oct 3 21:06:06 2001 From: carlseye@tampabay.rr.com (carl seyersdahl) Date: Wed, 3 Oct 2001 16:06:06 -0400 Subject: [AMPS] Problem with AL-811H References: Message-ID: <004801c14c46$e9740100$3da22041@tampabay.rr.com> The first place I would look is the coax,cable from the ant. relay to the output connector. I fought an amp , (not an al811) sometime back for quite some time before I decided to look in that area. It isn't the only place , maybe but it is one of many, and it's just not too obvious either!!!!! disconnect the rf choke on the output side and measure from the output connector to ground.have fun!!!! carl / kz5ca ----- Original Message ----- From: "Steve Katz" To: ; Sent: Wednesday, October 03, 2001 10:34 AM Subject: RE: [AMPS] Problem with AL-811H > > > > > > > I am attempting to repair an AL-811H for a friend. The amp has been > > abused due to mishandling as aircraft baggage making several trips to the > > Caribbean and back. The outer case shows several dings and one of the > > threaded holes in the chassis metal which holds the cover in place has > > been broken open. > > > > The reported symptoms are: When attempting to tune the amp upon return to > > home QTH, there was a pop and a flash inside the amp. > > > > ::Sounds like someone took a picture. Did you pose? > > > > On my bench, I am driving the amp using an Icom 751-A. The only visible > > signs of damage evident to any of the electronic components was one of the > > two 1000pF DC blocking capacitors from the anode/plate RFC to the tank > > circuit was cracked open slightly. I replaced these with two 500pF (6KV) > > capacitors for test purposes with no apparent difference in result. Using > > an ohm meter, it appears that the DC input blocking capacitors at the top > > end of the filament RF choke are good and that no short circuit to ground > > exists on the input. The tubes show no internal shorts using an ohm > > meter. The tubes light properly, the HV is 1700V and the anode idling > > current when keyed (without drive) is 150 mA (which is about right). > > > > I disassembled the rear pc board from the rear panel and inspected the > > traces for burns and shorts, but nothing was obvious. > > > > When attempting to operate the amp, the grid current and plate current > > swing up and down in synchronism with the drive, but NO RF output is > > observed. I am using a power meter and a Bird 2500 watt dummy load. > > Adjustment of the TUNE and LOAD capacitor produce no apparent dip nor > > power output. No unusual smell or noise is observed. > > > > ::This really sounds like a T-R relay not making contact, or possibly not > > even switching. I don't recall if the AL811H has a separate input relay > > and output relay, or if they're all one unit; however, the symptoms seem > > to indicate an open circuit between the plate tank and the coaxial output > > receptacle... > > > > Any suggestions would be greatly appreciated. > > > > Dave, WT8R > > > > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Wed Oct 3 22:03:26 2001 From: W8JI@contesting.com (Tom Rauch) Date: Wed, 3 Oct 2001 17:03:26 -0400 Subject: [AMPS] SB-220 In-Reply-To: <026a01c14c44$14690ac0$a7084c42@phil> Message-ID: <3BBB44DE.31711.217B6381@localhost> > They don't even want the box to be opened! > The minute construction is begun, the price drops > about $2 grand on a 220. > > E-Bay never ceases to amaze me....Collins, Drake, and un-built > Heaths bring unbelievable prices. > > (((73))) > Phil, K5PC I have a few dozen original SB-220 parts boxes and tape, plus the shipping boxes that were sent to me when I was doing work for Heath. I'm actually using them for trash boxes. It sounds like the boxes are worth $1500 each with packing tape. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Wed Oct 3 22:03:26 2001 From: W8JI@contesting.com (Tom Rauch) Date: Wed, 3 Oct 2001 17:03:26 -0400 Subject: [AMPS] Problem with AL-811H In-Reply-To: <004801c14c46$e9740100$3da22041@tampabay.rr.com> Message-ID: <3BBB44DE.13618.217B62F0@localhost> That isn't the problem being described Carl. The tubes arced, and the diode that protects the meters is now shorted. > The first place I would look is the coax,cable from the ant. relay to > the output connector. I fought an amp , (not an al811) sometime back > for quite some time before I decided to look in that area. It isn't > the only place , maybe but it is one of many, and it's just not too > obvious either!!!!! disconnect the rf choke on the output side and > measure from the output connector to ground.have fun!!!! > carl / kz5ca -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Wed Oct 3 22:32:39 2001 From: philk5pc@tyler.net (Phil Clements) Date: Wed, 3 Oct 2001 16:32:39 -0500 Subject: [AMPS] Problem with AL-811H References: <004801c14c46$e9740100$3da22041@tampabay.rr.com> Message-ID: <029001c14c52$ee295540$a7084c42@phil> > The first place I would look is the coax,cable from the ant. relay to the > output connector. I fought an amp , (not an al811) sometime back for quite > some time before I decided to look in that area. It isn't the only place , > maybe but it is one of many, and it's just not too obvious either!!!!! > disconnect the rf choke on the output side and measure from the output > connector to ground.have fun!!!! > carl / kz5ca Sage advice, Carl. I have seen that several times. Also, he can check to make sure the path from the blocking caps to the antenna connector is not open. Of course, the antenna relay will have to be energized to do this test. (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From phil@vaxxine.com Wed Oct 3 22:47:02 2001 From: phil@vaxxine.com (Phil (VA3UX)) Date: Wed, 03 Oct 2001 17:47:02 -0400 Subject: [AMPS] Noises in electrolytic capacitors In-Reply-To: <3BBACAF7.18989.1F9F223B@localhost> References: <5.0.2.1.0.20011002095801.009f3ec0@vaxxine.com> <200110021304.f92D4H312715@contesting.com> Message-ID: <5.0.2.1.0.20011003174344.009f11a0@vaxxine.com> At 08:23 AM 10/3/2001 -0400, Tom Rauch wrote: > > Thinking back a number of years, I had exactly the same experience > > with the equalizers in my Viewstar amp. Two of them were open, with > > absolutely no visual evidence that anything was wrong. > >While I have no idea specifically about the resistor used in that >case, when looking at the parts inherited from other "XXXXstar" >bankruptcy purchases many were surplus. These were all new parts when built Tom. Ohmite Brown Devils are still made. They're hollow core, wire-wound, glazed enamel. Physically, nice well made looking resistors. But that didn't seem to prevent the phenomenon of wire wounds opening-up for no apparent reason. Phil -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Wed Oct 3 23:30:23 2001 From: stevek@jmr.com (Steve Katz) Date: Wed, 3 Oct 2001 15:30:23 -0700 Subject: [AMPS] SB-220 Message-ID: The human species never ceases to amaze me. "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Tom Rauch [SMTP:w8ji@akorn.net] > Sent: Wednesday, October 03, 2001 2:03 PM > To: doug@nc.rr.com; Steve Katz; Phil Clements > Cc: amps@contesting.com > Subject: Re: [AMPS] SB-220 > > > They don't even want the box to be opened! > > The minute construction is begun, the price drops > > about $2 grand on a 220. > > > > E-Bay never ceases to amaze me....Collins, Drake, and un-built > > Heaths bring unbelievable prices. > > > > (((73))) > > Phil, K5PC > > I have a few dozen original SB-220 parts boxes and tape, plus the > shipping boxes that were sent to me when I was doing work for > Heath. I'm actually using them for trash boxes. > > It sounds like the boxes are worth $1500 each with packing tape. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From hostmaster@goproweb.net Wed Oct 3 22:08:09 2001 From: hostmaster@goproweb.net (Bill English) Date: Wed, 3 Oct 2001 17:08:09 -0400 Subject: [AMPS] Message-ID: First of all I would like to thank all of you for very useful information on this reflector. Most times it's extremely good reading. I was wondering if anyone had info on where mods for the Clipperton L could be found, I am interested in a good inrush protection circuit and warc band operation. Thanks to all Sig: The Mark of an expert isn't that he knows everything, it's that he knows where to look everything up. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Thu Oct 4 01:21:36 2001 From: W8JI@contesting.com (Tom Rauch) Date: Wed, 3 Oct 2001 20:21:36 -0400 Subject: [AMPS] Noises in electrolytic capacitors In-Reply-To: <5.0.2.1.0.20011003174344.009f11a0@vaxxine.com> References: <3BBACAF7.18989.1F9F223B@localhost> Message-ID: <3BBB7350.13869.2230D828@localhost> > These were all new parts when built Tom. Ohmite Brown Devils are > still made. They're hollow core, wire-wound, glazed enamel. > Physically, nice well made looking resistors. But that didn't seem to > prevent the phenomenon of wire wounds opening-up for no apparent > reason. Maybe so. The high failure resistors from Amp Supply and Ameritron's original AL80 were brand new IRC resistors from surplus channels. Same for some Vectronics and Viewstar parts. My point is you just never know. It's best to avoid surplus parts. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From wd7s@att.net Thu Oct 4 00:29:43 2001 From: wd7s@att.net (PAUL HEWITT) Date: Wed, 3 Oct 2001 18:29:43 -0500 Subject: [AMPS] YC-156 Input impedance In-Reply-To: <3BBB36EB.3788.2144E257@localhost> Message-ID: -----Original Message----- From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On Behalf Of Tom Rauch Sent: Wednesday, October 03, 2001 3:04 PM To: KD4LYH; amps@contesting.com; Phil Clements; PAUL HEWITT Subject: RE: [AMPS] YC-156 Input impedance > Do you know what values were used to > establish the load line used in your > Chaffe analysis? yes. Thank you for those figures > With fixed tuned input networks, > "ballpark" figures are of no use. They certainly are. You have to start somewhere. Anyone who thinks he can do a paper design or look at a operating sheet and not tweak anything is living in dream-land. So lets get in the ball park. 1500-3000 watts of output instead of the 10-14 thousand watts output quoted. My Chaffe analysis software for the yc-156 gives me an input impedance value of 40 ohms at 5kv plate voltage and 3KW output and it climbs to 47 ohms as I lower the output to power to 1500 watts, (VBmin 1200v both cases). If your software will give an answer for this lower output power could you please pass it along. Dreamland to me is not doing the math and "lifting" values from a data sheet using an entirely different set of operating parameters than I plan to use. Input network tweaking is required but (hopefully) not 25% or more or I've missed something on the paper design. Paul Hewitt -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Wt8r@aol.com Thu Oct 4 04:08:09 2001 From: Wt8r@aol.com (Wt8r@aol.com) Date: Wed, 3 Oct 2001 23:08:09 EDT Subject: [AMPS] Problem with AL-811H Message-ID: --part1_a4.1aaaa113.28ed2c99_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 10/3/01 5:11:07 PM Eastern Daylight Time, w8ji@akorn.net writes: > Subj: Re: [AMPS] Problem with AL-811H > Date: 10/3/01 5:11:07 PM Eastern Daylight Time > From: w8ji@akorn.net (Tom Rauch) > Sender: owner-amps@contesting.com > Reply-to: W8JI@contesting.com > To: carlseye@tampabay.rr.com (carl seyersdahl) > CC: amps@contesting.com > > >That isn't the problem being described Carl. > > The tubes arced, and the diode that protects the meters is now > shorted. ============================================================= > carl / kz5ca wrote: > > The first place I would look is the coax,cable from the ant. relay to > > the output connector. I fought an amp , (not an al811) sometime back > > for quite some time before I decided to look in that area. It isn't > > the only place , maybe but it is one of many, and it's just not too > > obvious either!!!!! disconnect the rf choke on the output side and > > measure from the output connector to ground.have fun!!!! > > carl / kz5ca > Carl, Thank you for accurately analyzing my problem. A cracked solder connection in the tank circuit (which was barely visible) turned out to be the problem. You seem to grasp the situation with a minimum of information. The tubes are all in good condition and the amplifier works well after redoing the joint. Thanks to all who offered suggestions which lead to the correct analysis of the problem. Regards & 73 de Dave, WT8R --part1_a4.1aaaa113.28ed2c99_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 10/3/01 5:11:07 PM Eastern Daylight Time, w8ji@akorn.net writes:

Subj: Re: [AMPS] Problem with AL-811H
Date: 10/3/01 5:11:07 PM Eastern Daylight Time
From:    w8ji@akorn.net (Tom Rauch)
Sender:    owner-amps@contesting.com
Reply-to:    W8JI@contesting.com
To:    carlseye@tampabay.rr.com (carl seyersdahl)
CC:    amps@contesting.com

>That isn't the problem being described Carl.

The tubes arced, and the diode that protects the meters is now
shorted.

=============================================================
carl / kz5ca wrote:

> The first place I would look is the coax,cable from the ant. relay to
> the output connector. I fought an amp , (not an al811) sometime back
> for quite some time before I decided to look in that area. It isn't
> the only place , maybe but it is one of many, and it's just not too
> obvious either!!!!! disconnect the rf choke on the output side and
> measure from the output connector to ground.have fun!!!!
>   carl / kz5ca
=============================================================

Carl,

Thank you for accurately analyzing my problem. A cracked solder connection in the tank circuit (which was barely visible) turned out to be the problem. You seem to grasp the situation with a minimum of information. The tubes are all in good condition and the amplifier works well after redoing the joint.

Thanks to all who offered suggestions which lead to the correct analysis of the problem.

Regards & 73 de

Dave, WT8R
--part1_a4.1aaaa113.28ed2c99_boundary-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From g8gsq@qsl.net Thu Oct 4 07:28:33 2001 From: g8gsq@qsl.net (Steve Thompson) Date: Thu, 4 Oct 2001 07:28:33 +0100 Subject: [AMPS] Noises in electrolytic capacitors Message-ID: <003401c14c9d$cb54e700$74877ad5@jackie> -----Original Message----- From: Phil (VA3UX) Cc: amps@contesting.com ; K4SO@aol.com Date: 04 October 2001 01:26 Subject: Re: [AMPS] Noises in electrolytic capacitors > >> These were all new parts when built Tom. Ohmite Brown Devils are >> still made. They're hollow core, wire-wound, glazed enamel. >> Physically, nice well made looking resistors. But that didn't seem to >> prevent the phenomenon of wire wounds opening-up for no apparent >> reason. I've seen numerous failures of products in the cell and paging base station industry from repeated expansion/contraction movement in component leads and coax inners. WW resistors have a degree of physical movement available in the wire. It's unlikely that a ham amp PSU goes through enough hot/cold cycles to cause failure that way, but it might contribute. Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From PhilHSS@Breathemail.net Thu Oct 4 14:44:19 2001 From: PhilHSS@Breathemail.net (Phil) Date: Thu, 4 Oct 2001 14:44:19 +0100 Subject: [AMPS] YC-156 Input impedance Message-ID: Gentlemen, I am in the process of assembling various bits of hardware to build an amplifier for HF using the YC-156. Hence, I'm watching the information on the reflector with great interest - not always a full understanding, but interest non-the-less! I am relatively new to the art of amplifier building, having only constructed with a GS23b for 70cms and a GS35b on 2m. As my design is in it's infancy, any light that you chaps can shine on the subject is gratefully received and noted. Keep up the good work! Regards, Phil G0HSS -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From nx7u@arrl.net Thu Oct 4 15:42:39 2001 From: nx7u@arrl.net (Scott Townley) Date: Thu, 04 Oct 2001 07:42:39 -0700 Subject: [AMPS] RF Electronics shut-down and more info Message-ID: <3BBC755F.796D64C@mindspring.com> ARRL web story http://www.arrl.org/news/stories/2001/10/02/3/?nc=1 The cited rules: 47CFR97.315 "Certification of External RF Power Amplifiers" http://frwebgate.access.gpo.gov/cgi-bin/get-cfr.cgi?TITLE=47&PART=97&SECTION=315&YEAR=2000&TYPE=TEXT 47CFR2.815 (Subpart I Marketing of Radio-frequency Devices) "External radio frequency power amplifiers" http://frwebgate.access.gpo.gov/cgi-bin/get-cfr.cgi?TITLE=47&PART=2&SECTION=815&YEAR=2000&TYPE=TEXT An Observation: In the past three years the FCC has been moving a lot of "boilerplate" regulations to part 2, like license renewal procedures, general technical requirements (like this), etc. Therefore in many cases it is no longer sufficient for amateurs to only be familiar with Part 97 but also with many portions of Part 2. Having dealt somewhat with the FCC professionally, I can relate that the best way to respond to them is "Yes Sir Right Away Sir". Very few cases are won on the "so prove me wrong" stance. As to the question from RF Electronics as to why Communications Concepts is allowed (thus far) to remain in business, I can only conjecture that the FCC doesn't consider CC as selling a "kit". On their website it's clear you get parts but no instructions outside of the applicable Motorola Application Note. And having seen those, I couldn't call them kit instructions. As to the other peripheral comments about future sales of parts/tubes, etc., read the WHOLE rule set. Making decisions based on partial exerpts is inevitably out of context and largely meaningless (all the peripheral concerns I've seen thus far are in fact addressed in the whole of the rules). -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Thu Oct 4 16:11:37 2001 From: 2@vc.net (2) Date: Thu, 4 Oct 2001 08:11:37 -0700 Subject: [AMPS] Problem with AL-811H Message-ID: <200110041511.f94FBeZ28444@contesting.com> >In a message dated 10/3/01 5:11:07 PM Eastern Daylight Time, w8ji@akorn.net >writes: > > >> Subj: Re: [AMPS] Problem with AL-811H >> Date: 10/3/01 5:11:07 PM Eastern Daylight Time >> From: w8ji@akorn.net (Tom Rauch) >> Sender: owner-amps@contesting.com >> Reply-to: W8JI@contesting.com >> To: carlseye@tampabay.rr.com (carl seyersdahl) >> CC: amps@contesting.com >> >> >That isn't the problem being described Carl. >> >> The tubes arced, and the diode that protects the meters is now >> shorted. >============================================================= >> carl / kz5ca wrote: > >> > The first place I would look is the coax,cable from the ant. relay to >> > the output connector. I fought an amp , (not an al811) sometime back >> > for quite some time before I decided to look in that area. It isn't >> > the only place , maybe but it is one of many, and it's just not too >> > obvious either!!!!! disconnect the rf choke on the output side and >> > measure from the output connector to ground.have fun!!!! >> > carl / kz5ca >> >Carl, > >Thank you for accurately analyzing my problem. A cracked solder connection >in the tank circuit (which was barely visible) turned out to be the >problem. // I don't see how an out of resonance tank could cause the meter protection diodes to short and the tubes to arc. What kind of diodes shorted? My guess is that Murphy was right in that everything is more complicated than it first appears. - cheers >You seem to grasp the situation with a minimum of information. The tubes >are >all in good condition and the amplifier works well after redoing the joint. > >Thanks to all who offered suggestions which lead to the correct analysis of >the problem. > >Regards & 73 de > >Dave, WT8R > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Thu Oct 4 16:11:42 2001 From: 2@vc.net (2) Date: Thu, 4 Oct 2001 08:11:42 -0700 Subject: [AMPS] Noises in electrolytic capacitors Message-ID: <200110041511.f94FBiZ28450@contesting.com> > > >-----Original Message----- > >From: Phil (VA3UX) >Cc: amps@contesting.com ; K4SO@aol.com >Date: 04 October 2001 01:26 >Subject: Re: [AMPS] Noises in electrolytic capacitors > > >> >>> These were all new parts when built Tom. Ohmite Brown Devils are >>> still made. They're hollow core, wire-wound, glazed enamel. >>> Physically, nice well made looking resistors. But that didn't seem to >>> prevent the phenomenon of wire wounds opening-up for no apparent >>> reason. >I've seen numerous failures of products in the cell and paging base station >industry from repeated expansion/contraction movement in component leads and >coax inners. WW resistors have a degree of physical movement available in >the wire. It's unlikely that a ham amp PSU goes through enough hot/cold >cycles to cause failure that way, but it might contribute. > // Two reasons that we chose to carry Matsushita MOF equalizer resistors is the low failure rate and the superb accuracy. So far, we have sold more than 7,000 units and there has not been a reported failure. However, with high-R wire-wound equalizer resistors, this is hardly the case My guess is that hot-cold, on-off cycling is one reason for this since Ni-Cr alloys have a coefficient of temperature expansion-rate that is different than glass or ceramic. So how does one know if the resistance of the equalizers is sufficient? Measure the V across each electrolytic filter capacitor. If the voltages are within a few percent, chances are that there will be fewer surprises during the next contest. cheers, Steve > > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From PhilHSS@Breathemail.net Thu Oct 4 16:22:23 2001 From: PhilHSS@Breathemail.net (Phil) Date: Thu, 4 Oct 2001 16:22:23 +0100 Subject: [AMPS] DOD006 / RCA-7213 Tubes Message-ID: Gentlemen, Does anyone know if DOD006 Tubes can be made to 'go' on 23cms at all, please? I believe that the DOD006 is much the same as an RCA-7213 tube which can operate up to 1200MHz or so, but is 1296MHz pushing things too far? What level of RF might be produced? I suspect that it may be the case that I'll have to use the tube at a lower frequency - I have a design where they operate at 1500w output at 70cms for instance. Using it on HF might be interesting....! Thanks and Regards , Phil G0HSS -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Ian White, G3SEK" References: Message-ID: Phil wrote: > >Gentlemen, > >Does anyone know if DOD006 Tubes can be made to 'go' on 23cms at all, >please? I believe that the DOD006 is much the same as an RCA-7213 tube which >can operate up to 1200MHz or so, but is 1296MHz pushing things too far? What >level of RF might be produced? > >I suspect that it may be the case that I'll have to use the tube at a lower >frequency - I have a design where they operate at 1500w output at 70cms for >instance. Using it on HF might be interesting....! > A real 7213 works fine at 432, but a DOD006 isn't quite the same. As far as I know, only G3LTF has made a DOD006 work well at 432, though they work fine at 144 and, yes, even on HF. I haven't heard of anyone making even a real 7213 work at 1296MHz with useful gain, efficiency or power output. 73 from Ian G3SEK Editor, 'The VHF/UHF DX Book' 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.com/g3sek -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From n1nk@home.com Fri Oct 5 00:52:26 2001 From: n1nk@home.com (Jim Spears) Date: Thu, 4 Oct 2001 19:52:26 -0400 Subject: [AMPS] vom check of 3-500Z tubes Message-ID: <00f601c14d2f$9ef5e000$9348fea9@ports1.ri.home.com> my amp supply lk-500 zb did a funny thing a while back when I powered it up after a long time in the closet and a cross country move. so far I have found a blown 1 ohm, 5 watt wire wound resistor. it was in two pieces so there is little debate on whether or not it blew... one area that was suggested as a potential problem was an internal short in one or both tubes. I pulled them and did a vom check for short vs open across all pin combinations. both tubes are eimac 3-500z if one looks at the bottom of the tube with the plate away, there are 5 pins. one is by itself and the other 4 make up the rest of the array. I see short (0 ohms) from the pin by itself and its two neighbors and open between any of these and either the plate or the other pins. I see short between the remaining 2 pins and open between these and either the plate or the other pins. when I say short, I mean 0 ohms as measured by my cheapo radio shack digital vom; not sure I could tell the difference between 0 ohms and the resistance across the filament which should be some small number. I would guess that the 3 pin set are connections to the grid and the 2 pin set is the filament. so from a low voltage standpoint, it does not look like there is a short between either the filament or the grid and the plate nor between the grid and the plate nor between the filament and the grid. maybe at 3000 vdc, things change... comments? jim N1NK x AB6R -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ko4nrbs@yahoo.com Fri Oct 5 03:08:17 2001 From: ko4nrbs@yahoo.com (Bill Smith) Date: Thu, 4 Oct 2001 19:08:17 -0700 (PDT) Subject: [AMPS] ALPHA 374A Message-ID: <20011005020817.7248.qmail@web20506.mail.yahoo.com> I've found a Alpha 374A amplifier that has not been used for several years. The guy says he'll sell it but does not know what it may be worth. It is in very clean condition and when checked out today had full output. It is in orginial condition with no mods. It's pretty obvious this amp has not been used much!! There isn't a scratch on it anywhere. What is a fair market price for this amp? Does the Alpha 374A have a good reputation? 73, Bill Smith KO4NR ===== Bill Smith KO4NR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 5 03:28:13 2001 From: 2@vc.net (2) Date: Thu, 4 Oct 2001 19:28:13 -0700 Subject: [AMPS] vom check of 3-500Z tubes Message-ID: <200110050228.f952SFZ11204@contesting.com> > >my amp supply lk-500 zb did a funny thing a while back when I powered it up >after a long time in the closet and a cross country move. so far I have >found a blown 1 ohm, 5 watt wire wound resistor. it was in two pieces so >there is little debate on whether or not it blew... > // Where was it in the circuit? >one area that was suggested as a potential problem was an internal short in >one or both tubes. > // If you can see the anoode cooler touching the grid, you have an internal short. >I pulled them and did a vom check for short vs open across all pin >combinations. both tubes are eimac 3-500z > >if one looks at the bottom of the tube with the plate away, there are 5 >pins. one is by itself // This is pin 3. Count clockwise. Pins 2, 3, 4 are grid. Pins 1 and 5 are filament. > and the other 4 make up the rest of the array. ... ... >I would guess that the 3 pin set are connections to the grid and the 2 pin >set is the filament. > >so from a low voltage standpoint, it does not look like there is a short >between either the filament or the grid and the plate nor between the grid >and the plate nor between the filament and the grid. maybe at 3000 vdc, >things change... > >comments? > // If the anode cooler is not touching the grid, I would suspect a parasite. >jim >N1NK >x AB6R > > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From hostmaster@goproweb.net Fri Oct 5 03:46:00 2001 From: hostmaster@goproweb.net (Bill English) Date: Thu, 4 Oct 2001 22:46:00 -0400 Subject: [AMPS] Message-ID: Hello all, anyone out there have an idea as to a fair market price on a working Henry 2K4 amp? As I have a chance to get one, I would like to know if there are any land mines to look out for. Thanks, Bill/W4VD Sig: The Mark of an expert isn't that he knows everything, it's that he knows where to look everything up. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ko4nrbs@yahoo.com Fri Oct 5 10:46:43 2001 From: ko4nrbs@yahoo.com (Bill Smith) Date: Fri, 5 Oct 2001 02:46:43 -0700 (PDT) Subject: [AMPS] 500 pf 6kv Ceramic Disc Capacitors Message-ID: <20011005094643.25866.qmail@web20502.mail.yahoo.com> Looking for a couple 500 pf 6KV ceramic disc capacitors. They are not the doorknob type. Thanks, Bill Smith KO4NR ===== Bill Smith KO4NR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From kce@freeway.net Fri Oct 5 12:30:24 2001 From: kce@freeway.net (kenneth m cubilo) Date: Fri, 05 Oct 2001 07:30:24 -0400 Subject: [AMPS] re al1500 Message-ID: <3BBD99D0.878327A5@freeway.net> hi i have a change to pick up a ameritron al1500 amp, anyone out here have any pros or cons on this critter? thanks ken w8ob -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w2ge@home.com Fri Oct 5 13:02:03 2001 From: w2ge@home.com (Phil Levin W2GE) Date: Fri, 5 Oct 2001 08:02:03 -0400 Subject: [AMPS] re al1500 Message-ID: Con, 3 minute warm up time on an 8877... Some argue over the lack of parasitic suppressor and some tube reliability issues..... Personally the AL1200 is more of a war horse... its a contesters favorite, like the energizer bunny.... Phil W2GE -----Original Message----- From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On Behalf Of kenneth m cubilo Sent: Friday, October 05, 2001 7:30 AM To: amps@contesting.com Subject: [AMPS] re al1500 hi i have a change to pick up a ameritron al1500 amp, anyone out here have any pros or cons on this critter? thanks ken w8ob -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 5 15:24:08 2001 From: 2@vc.net (2) Date: Fri, 5 Oct 2001 07:24:08 -0700 Subject: [AMPS] re al1500 Message-ID: <200110051424.f95EO8Z21716@contesting.com> > > > >Con, 3 minute warm up time on an 8877... > // This isn't much of a problem if the station operator switches on the 8877's heater whenever the transceiver is switched on. > >Some argue over the lack of parasitic suppressor and some tube reliability >issues..... > // There are more than a few AL-1500 owners who have gone through more than a few 8877s during the first 12-months. Nacherly, the expert who designed the AL-1500 blames Eimac. /see Figure 24 on my Web site/ The long excursion on the wide river in the Land of the Pharoahs continues. - Before purchasing a used AL-1500 amplifier, I would perform the Funderberg gold sputter test on the 8877. This test is described on my Web site. The test takes about a minute. >Personally the AL1200 is more of a war horse... its a contesters favorite, >like the energizer bunny.... > // Even though the 3cx1200A7 has about 10-times as much feedback-C as a 3cx1200Z7, and, understandably, has a well deserved reputation for squirrelish antics and big bangs, the filament helices are not nearly as subject to bending as a 3-500Z's, so grid-filament shorts are rare following a big bang. However, If I owned an AL-1200, or any MFJ-Ameritron amplifier, I would add a suitable glitch resistor in series with the positive lead of the anode supply. cheers, Phil W2GE > >-----Original Message----- >From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On >Behalf Of kenneth m cubilo >Sent: Friday, October 05, 2001 7:30 AM >To: amps@contesting.com >Subject: [AMPS] re al1500 > > > >hi i have a change to pick up a ameritron al1500 amp, anyone out here >have any pros or cons on this critter? >thanks ken w8ob > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 5 15:24:10 2001 From: 2@vc.net (2) Date: Fri, 5 Oct 2001 07:24:10 -0700 Subject: [AMPS] Message-ID: <200110051424.f95EOAZ21720@contesting.com> > >Hello all, > >anyone out there have an idea as to a fair market price on a working Henry >2K4 amp? As I have a chance to get one, I would like to know if there are >any land mines to look out for. > >Thanks, >Bill/W4VD > > >Sig: The Mark of an expert isn't that he knows everything, it's that he >knows where to look everything up. > // I know of one "expert" on AMPS who makes stuff up. > cheers, Bill >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Fri Oct 5 15:22:18 2001 From: stevek@jmr.com (Steve Katz) Date: Fri, 5 Oct 2001 07:22:18 -0700 Subject: [AMPS] ALPHA 374A Message-ID: I purchased a 374A in "mint" condition a few years ago for $1295, and felt that was a reasonably good deal. Obviously, the cost of three new replacement tubes is about that! For one with very few hours on the tubes and in factory-fresh condition, I'd have likely paid a bit more. When you say "full output," is that in the bandpass (no-tune) mode? If so, and you get full output on 10m in the bandpass mode, that's wonderful, and unusual for such an oldie, probably means the owner never messed with it! Only caveat I can think of is that the 374A needs to be installed where there's a lot of breathing room behind it. It does not vent or exhaust out the top, but out the rear, and the output duct is very small (as you've likely noticed) and blows a steady stream of very hot air under key-down condx. That air needs to blow, unrestricted, for quite a distance. I wouldn't place anything behind the amp for about 12" or so. Other than that, it's a rather amazing amp that has proven itself a workhorse in hundreds of contest stations around the world... WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Bill Smith [SMTP:ko4nrbs@yahoo.com] > Sent: Thursday, October 04, 2001 7:08 PM > To: amps@contesting.com > Subject: [AMPS] ALPHA 374A > > > I've found a Alpha 374A amplifier that has not been > used for several years. The guy says he'll sell it > but does not know what it may be worth. It is in very > clean condition and when checked out today had full > output. It is in orginial condition with no mods. > It's pretty obvious this amp has not been used much!! > There isn't a scratch on it anywhere. > > What is a fair market price for this amp? Does the > Alpha 374A have a good reputation? > 73, > Bill Smith KO4NR > > ===== > Bill Smith KO4NR > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Fri Oct 5 15:28:31 2001 From: W8JI@contesting.com (Tom Rauch) Date: Fri, 5 Oct 2001 10:28:31 -0400 Subject: [AMPS] vom check of 3-500Z tubes In-Reply-To: <00f601c14d2f$9ef5e000$9348fea9@ports1.ri.home.com> Message-ID: <3BBD8B4F.14599.2A5EE2FB@localhost> > my amp supply lk-500 zb did a funny thing a while back when I powered > it up after a long time in the closet and a cross country move. so > far I have found a blown 1 ohm, 5 watt wire wound resistor. it was in > two pieces so there is little debate on whether or not it blew... Most likely you have a gas problem with the tubes. That is normal for tubes that sit a long time, especially tubes that might have had the seals operated at elevated temperatures prior to sitting. You can not test that with a VOM. You need a high voltage tester. You should have a breakdown of 11kV or more from anode to grid in a good 3-500Z. The grid is the offset pin, and the two adjacent pins. The remaining two pins are filament. > one area that was suggested as a potential problem was an internal > short in one or both tubes. Yep, and it most likely is gas. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w6ru@bak.rr.com Fri Oct 5 16:35:34 2001 From: w6ru@bak.rr.com (Terry Gaiser) Date: Fri, 5 Oct 2001 08:35:34 -0700 Subject: [AMPS] ALPHA 374A References: Message-ID: <000901c14db3$6038bb60$6501a8c0@amd14gig> I think you are mistaken ... the 374A does exhaust out the top ... has 2 tubes ... no bandpass mode on 10 meters. Terry W6RU ----- Original Message ----- From: Steve Katz To: 'Bill Smith' ; Sent: Friday, October 05, 2001 7:22 AM Subject: RE: [AMPS] ALPHA 374A > > I purchased a 374A in "mint" condition a few years ago for $1295, and felt > that was a reasonably good deal. Obviously, the cost of three new > replacement tubes is about that! For one with very few hours on the tubes > and in factory-fresh condition, I'd have likely paid a bit more. > > When you say "full output," is that in the bandpass (no-tune) mode? If so, > and you get full output on 10m in the bandpass mode, that's wonderful, and > unusual for such an oldie, probably means the owner never messed with it! > > Only caveat I can think of is that the 374A needs to be installed where > there's a lot of breathing room behind it. It does not vent or exhaust out > the top, but out the rear, and the output duct is very small (as you've > likely noticed) and blows a steady stream of very hot air under key-down > condx. That air needs to blow, unrestricted, for quite a distance. I > wouldn't place anything behind the amp for about 12" or so. Other than > that, it's a rather amazing amp that has proven itself a workhorse in > hundreds of contest stations around the world... > > WB2WIK/6 > > "Each success only buys an admission ticket to a more difficult problem." -- > Henry Kissinger > > > -----Original Message----- > > From: Bill Smith [SMTP:ko4nrbs@yahoo.com] > > Sent: Thursday, October 04, 2001 7:08 PM > > To: amps@contesting.com > > Subject: [AMPS] ALPHA 374A > > > > > > I've found a Alpha 374A amplifier that has not been > > used for several years. The guy says he'll sell it > > but does not know what it may be worth. It is in very > > clean condition and when checked out today had full > > output. It is in orginial condition with no mods. > > It's pretty obvious this amp has not been used much!! > > There isn't a scratch on it anywhere. > > > > What is a fair market price for this amp? Does the > > Alpha 374A have a good reputation? > > 73, > > Bill Smith KO4NR > > > > ===== > > Bill Smith KO4NR > > > > -- > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > Submissions: amps@contesting.com > > Administrative requests: amps-REQUEST@contesting.com > > Problems: owner-amps@contesting.com > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k8cpa@arrl.net Fri Oct 5 15:51:47 2001 From: k8cpa@arrl.net (chuck) Date: Fri, 05 Oct 2001 10:51:47 -0400 Subject: [AMPS] In-Reply-To: <200110051424.f95EOAZ21720@contesting.com> Message-ID: <3.0.6.32.20011005105147.00832220@pop3.norton.antivirus> >// I know of one "expert" on AMPS who makes stuff up. > Yup. and you're one of them. Cheers. -Chuck -Chuck Adkins K8CPA Drummer, Guitar Player, Ham Radio, Jesus Freak Type Person at Large http://www.qsl.net/k8cpa k8cpa@arrl.net ---------------------------------------------------- Sign Up for NetZero Platinum Today Only $9.95 per month! http://my.netzero.net/s/signup?r=platinum&refcd=PT97 -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From hostmaster@goproweb.net Fri Oct 5 16:30:32 2001 From: hostmaster@goproweb.net (Bill English) Date: Fri, 5 Oct 2001 11:30:32 -0400 Subject: [AMPS] RE Henry 2K4 Message-ID: Do these work very well on 17 and 12?? Bill/W4VD Sig: The Mark of an expert isn't that he knows everything, it's that he knows where to look everything up. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Fri Oct 5 17:43:30 2001 From: stevek@jmr.com (Steve Katz) Date: Fri, 5 Oct 2001 09:43:30 -0700 Subject: [AMPS] ALPHA 374A Message-ID: Not my 374A! Hmmmm...it's possible they changed something during the multi-year sales cycle of this product, but the "374" meant "3 x 8874" and used 3 tubes -- at least mine does. They also had a "274" which was "2 x 8874" and used two tubes. Mine exhausts out the rear, exclusively. There's no holes in the top, at all. WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Terry Gaiser [SMTP:w6ru@bak.rr.com] > Sent: Friday, October 05, 2001 8:36 AM > To: Steve Katz; 'Bill Smith'; amps@contesting.com > Subject: Re: [AMPS] ALPHA 374A > > I think you are mistaken ... the 374A does exhaust out the top ... has 2 > tubes ... no bandpass mode on 10 meters. > Terry W6RU > > ----- Original Message ----- > From: Steve Katz > To: 'Bill Smith' ; > Sent: Friday, October 05, 2001 7:22 AM > Subject: RE: [AMPS] ALPHA 374A > > > > > > I purchased a 374A in "mint" condition a few years ago for $1295, and > felt > > that was a reasonably good deal. Obviously, the cost of three new > > replacement tubes is about that! For one with very few hours on the > tubes > > and in factory-fresh condition, I'd have likely paid a bit more. > > > > When you say "full output," is that in the bandpass (no-tune) mode? If > so, > > and you get full output on 10m in the bandpass mode, that's wonderful, > and > > unusual for such an oldie, probably means the owner never messed with > it! > > > > Only caveat I can think of is that the 374A needs to be installed where > > there's a lot of breathing room behind it. It does not vent or exhaust > out > > the top, but out the rear, and the output duct is very small (as you've > > likely noticed) and blows a steady stream of very hot air under key-down > > condx. That air needs to blow, unrestricted, for quite a distance. I > > wouldn't place anything behind the amp for about 12" or so. Other than > > that, it's a rather amazing amp that has proven itself a workhorse in > > hundreds of contest stations around the world... > > > > WB2WIK/6 > > > > "Each success only buys an admission ticket to a more difficult > problem." -- > > Henry Kissinger > > > > > -----Original Message----- > > > From: Bill Smith [SMTP:ko4nrbs@yahoo.com] > > > Sent: Thursday, October 04, 2001 7:08 PM > > > To: amps@contesting.com > > > Subject: [AMPS] ALPHA 374A > > > > > > > > > I've found a Alpha 374A amplifier that has not been > > > used for several years. The guy says he'll sell it > > > but does not know what it may be worth. It is in very > > > clean condition and when checked out today had full > > > output. It is in orginial condition with no mods. > > > It's pretty obvious this amp has not been used much!! > > > There isn't a scratch on it anywhere. > > > > > > What is a fair market price for this amp? Does the > > > Alpha 374A have a good reputation? > > > 73, > > > Bill Smith KO4NR > > > > > > ===== > > > Bill Smith KO4NR > > > > > > -- > > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > > Submissions: amps@contesting.com > > > Administrative requests: amps-REQUEST@contesting.com > > > Problems: owner-amps@contesting.com > > > > -- > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > Submissions: amps@contesting.com > > Administrative requests: amps-REQUEST@contesting.com > > Problems: owner-amps@contesting.com > > > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 5 18:18:55 2001 From: 2@vc.net (2) Date: Fri, 5 Oct 2001 10:18:55 -0700 Subject: [AMPS] Message-ID: <200110051718.f95HItZ26238@contesting.com> > >>// I know of one "expert" on AMPS who makes stuff up. >> > > >Yup. and you're one of them. > // An example, please. > tnx, Chuck > > >-Chuck Adkins K8CPA >Drummer, Guitar Player, Ham Radio, Jesus Freak Type Person at Large >http://www.qsl.net/k8cpa >k8cpa@arrl.net > > >---------------------------------------------------- >Sign Up for NetZero Platinum Today >Only $9.95 per month! >http://my.netzero.net/s/signup?r=platinum&refcd=PT97 > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 5 18:18:57 2001 From: 2@vc.net (2) Date: Fri, 5 Oct 2001 10:18:57 -0700 Subject: [AMPS] vom check of 3-500Z tubes Message-ID: <200110051718.f95HIuZ26244@contesting.com> > >> my amp supply lk-500 zb did a funny thing a while back when I powered >> it up after a long time in the closet and a cross country move. so >> far I have found a blown 1 ohm, 5 watt wire wound resistor. it was in >> two pieces so there is little debate on whether or not it blew... > >Most likely you have a gas problem with the tubes. That is normal >for tubes that sit a long time, especially tubes that might have had >the seals operated at elevated temperatures prior to sitting. > >You can not test that with a VOM. You need a high voltage tester. > >You should have a breakdown of 11kV or more from anode to grid >in a good 3-500Z. > >The grid is the offset pin, and the two adjacent pins. The remaining two >pins are filament. > >> one area that was suggested as a potential problem was an internal >> short in one or both tubes. > >Yep, and it most likely is gas. > // However, it could be vanishing gas that disappears seconds before the tube is connected to a high-potential tester. Normal leakage is <10uA @ 8kV. If you see >50uA leakage, it's regular gas that blew the 1 ohm, 5 watt wire wound resistor.. If you see <10uA leakage, it's vanishing gas that blew the 1 ohm, 5 watt wire wound resistor. cheers - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w6ru@bak.rr.com Fri Oct 5 19:41:53 2001 From: w6ru@bak.rr.com (Terry Gaiser) Date: Fri, 5 Oct 2001 11:41:53 -0700 Subject: [AMPS] ALPHA 374A References: Message-ID: <001901c14dcd$6d2d3c00$6501a8c0@amd14gig> What you describe is the "374" not a "374A" ... 2 different amplifiers. Terry W6RU ----- Original Message ----- From: Steve Katz To: 'Terry Gaiser' ; 'Bill Smith' ; Sent: Friday, October 05, 2001 9:43 AM Subject: RE: [AMPS] ALPHA 374A > Not my 374A! Hmmmm...it's possible they changed something during the > multi-year sales cycle of this product, but the "374" meant "3 x 8874" and > used 3 tubes -- at least mine does. They also had a "274" which was "2 x > 8874" and used two tubes. Mine exhausts out the rear, exclusively. There's > no holes in the top, at all. > > WB2WIK/6 > > "Each success only buys an admission ticket to a more difficult problem." -- > Henry Kissinger > > > -----Original Message----- > > From: Terry Gaiser [SMTP:w6ru@bak.rr.com] > > Sent: Friday, October 05, 2001 8:36 AM > > To: Steve Katz; 'Bill Smith'; amps@contesting.com > > Subject: Re: [AMPS] ALPHA 374A > > > > I think you are mistaken ... the 374A does exhaust out the top ... has 2 > > tubes ... no bandpass mode on 10 meters. > > Terry W6RU > > > > ----- Original Message ----- > > From: Steve Katz > > To: 'Bill Smith' ; > > Sent: Friday, October 05, 2001 7:22 AM > > Subject: RE: [AMPS] ALPHA 374A > > > > > > > > > > I purchased a 374A in "mint" condition a few years ago for $1295, and > > felt > > > that was a reasonably good deal. Obviously, the cost of three new > > > replacement tubes is about that! For one with very few hours on the > > tubes > > > and in factory-fresh condition, I'd have likely paid a bit more. > > > > > > When you say "full output," is that in the bandpass (no-tune) mode? If > > so, > > > and you get full output on 10m in the bandpass mode, that's wonderful, > > and > > > unusual for such an oldie, probably means the owner never messed with > > it! > > > > > > Only caveat I can think of is that the 374A needs to be installed where > > > there's a lot of breathing room behind it. It does not vent or exhaust > > out > > > the top, but out the rear, and the output duct is very small (as you've > > > likely noticed) and blows a steady stream of very hot air under key-down > > > condx. That air needs to blow, unrestricted, for quite a distance. I > > > wouldn't place anything behind the amp for about 12" or so. Other than > > > that, it's a rather amazing amp that has proven itself a workhorse in > > > hundreds of contest stations around the world... > > > > > > WB2WIK/6 > > > > > > "Each success only buys an admission ticket to a more difficult > > problem." -- > > > Henry Kissinger > > > > > > > -----Original Message----- > > > > From: Bill Smith [SMTP:ko4nrbs@yahoo.com] > > > > Sent: Thursday, October 04, 2001 7:08 PM > > > > To: amps@contesting.com > > > > Subject: [AMPS] ALPHA 374A > > > > > > > > > > > > I've found a Alpha 374A amplifier that has not been > > > > used for several years. The guy says he'll sell it > > > > but does not know what it may be worth. It is in very > > > > clean condition and when checked out today had full > > > > output. It is in orginial condition with no mods. > > > > It's pretty obvious this amp has not been used much!! > > > > There isn't a scratch on it anywhere. > > > > > > > > What is a fair market price for this amp? Does the > > > > Alpha 374A have a good reputation? > > > > 73, > > > > Bill Smith KO4NR > > > > > > > > ===== > > > > Bill Smith KO4NR > > > > > > > > -- > > > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > > > Submissions: amps@contesting.com > > > > Administrative requests: amps-REQUEST@contesting.com > > > > Problems: owner-amps@contesting.com > > > > > > -- > > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > > Submissions: amps@contesting.com > > > Administrative requests: amps-REQUEST@contesting.com > > > Problems: owner-amps@contesting.com > > > > > > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Fri Oct 5 18:40:15 2001 From: stevek@jmr.com (Steve Katz) Date: Fri, 5 Oct 2001 10:40:15 -0700 Subject: [AMPS] ALPHA 374A Message-ID: Hi Terry, You know, you might be right! My manual is for the 374A, but since I'm at the office and not home, I can't look at the front panel... I recall (I think) the original 374 had a natural aluminum colored front panel, which mine does not (it's brown/tan). What do you have and when was it mf'd? -Steve WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Terry Gaiser [SMTP:w6ru@bak.rr.com] > Sent: Friday, October 05, 2001 11:42 AM > To: Steve Katz; 'Bill Smith'; amps@contesting.com > Subject: Re: [AMPS] ALPHA 374A > > What you describe is the "374" not a "374A" ... 2 different amplifiers. > Terry W6RU > > ----- Original Message ----- > From: Steve Katz > To: 'Terry Gaiser' ; 'Bill Smith' ; > > Sent: Friday, October 05, 2001 9:43 AM > Subject: RE: [AMPS] ALPHA 374A > > > > Not my 374A! Hmmmm...it's possible they changed something during the > > multi-year sales cycle of this product, but the "374" meant "3 x 8874" > and > > used 3 tubes -- at least mine does. They also had a "274" which was "2 > x > > 8874" and used two tubes. Mine exhausts out the rear, exclusively. > There's > > no holes in the top, at all. > > > > WB2WIK/6 > > > > "Each success only buys an admission ticket to a more difficult > problem." -- > > Henry Kissinger > > > > > -----Original Message----- > > > From: Terry Gaiser [SMTP:w6ru@bak.rr.com] > > > Sent: Friday, October 05, 2001 8:36 AM > > > To: Steve Katz; 'Bill Smith'; amps@contesting.com > > > Subject: Re: [AMPS] ALPHA 374A > > > > > > I think you are mistaken ... the 374A does exhaust out the top ... has > 2 > > > tubes ... no bandpass mode on 10 meters. > > > Terry W6RU > > > > > > ----- Original Message ----- > > > From: Steve Katz > > > To: 'Bill Smith' ; > > > Sent: Friday, October 05, 2001 7:22 AM > > > Subject: RE: [AMPS] ALPHA 374A > > > > > > > > > > > > > > I purchased a 374A in "mint" condition a few years ago for $1295, > and > > > felt > > > > that was a reasonably good deal. Obviously, the cost of three new > > > > replacement tubes is about that! For one with very few hours on the > > > tubes > > > > and in factory-fresh condition, I'd have likely paid a bit more. > > > > > > > > When you say "full output," is that in the bandpass (no-tune) mode? > If > > > so, > > > > and you get full output on 10m in the bandpass mode, that's > wonderful, > > > and > > > > unusual for such an oldie, probably means the owner never messed > with > > > it! > > > > > > > > Only caveat I can think of is that the 374A needs to be installed > where > > > > there's a lot of breathing room behind it. It does not vent or > exhaust > > > out > > > > the top, but out the rear, and the output duct is very small (as > you've > > > > likely noticed) and blows a steady stream of very hot air under > key-down > > > > condx. That air needs to blow, unrestricted, for quite a distance. > I > > > > wouldn't place anything behind the amp for about 12" or so. Other > than > > > > that, it's a rather amazing amp that has proven itself a workhorse > in > > > > hundreds of contest stations around the world... > > > > > > > > WB2WIK/6 > > > > > > > > "Each success only buys an admission ticket to a more difficult > > > problem." -- > > > > Henry Kissinger > > > > > > > > > -----Original Message----- > > > > > From: Bill Smith [SMTP:ko4nrbs@yahoo.com] > > > > > Sent: Thursday, October 04, 2001 7:08 PM > > > > > To: amps@contesting.com > > > > > Subject: [AMPS] ALPHA 374A > > > > > > > > > > > > > > > I've found a Alpha 374A amplifier that has not been > > > > > used for several years. The guy says he'll sell it > > > > > but does not know what it may be worth. It is in very > > > > > clean condition and when checked out today had full > > > > > output. It is in orginial condition with no mods. > > > > > It's pretty obvious this amp has not been used much!! > > > > > There isn't a scratch on it anywhere. > > > > > > > > > > What is a fair market price for this amp? Does the > > > > > Alpha 374A have a good reputation? > > > > > 73, > > > > > Bill Smith KO4NR > > > > > > > > > > ===== > > > > > Bill Smith KO4NR > > > > > > > > > > -- > > > > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > > > > Submissions: amps@contesting.com > > > > > Administrative requests: amps-REQUEST@contesting.com > > > > > Problems: owner-amps@contesting.com > > > > > > > > -- > > > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > > > Submissions: amps@contesting.com > > > > Administrative requests: amps-REQUEST@contesting.com > > > > Problems: owner-amps@contesting.com > > > > > > > > > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From rrossi@btv.ibm.com Fri Oct 5 19:27:25 2001 From: rrossi@btv.ibm.com (Ron D. Rossi) Date: Fri, 05 Oct 2001 14:27:25 -0400 Subject: [AMPS] vom check of 3-500Z tubes In-Reply-To: <200110051718.f95HIuZ26244@contesting.com> Message-ID: <200110051827.OAA30130@johnpaul.btv.ibm.com> Jim Spears" said: > > > > >> my amp supply lk-500 zb did a funny thing a while back when I powered > >> it up after a long time in the closet and a cross country move. so > >> far I have found a blown 1 ohm, 5 watt wire wound resistor. it was in > >> two pieces so there is little debate on whether or not it blew... I am one of the least experienced amplifier debuggers on the reflector having only debugged and repaired five HF amplifiers (some more than once due to severe contest quest-op abuse). I have spent a great deal of time however troubleshooting other electronic things in my career. I try to start with an open mind to the problem. Root cause determination is a methodical process. Analyze the failure and then take the simplest and least expensive steps first working toward the more expensive and exotic. In this case DC check the tubes, look for obvious arcing or a discharge path, inspect and measure critical components in the path. Then replace the resistor and try again! Dust, bugs, errant shards of solder, etc. could surely trigger the disappearing glitch resistor trick. Doesn't it make sense after following the steps above to just replace the resistor and fire the rig up again? Then take the next step. I stand ready to be corrected! -- 73 es God Bless de KK1L...ron (kk1l@arrl.net) <>< QTH: Jericho, Vermont My page: http://www.qsl.net/kk1l -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Fri Oct 5 19:29:50 2001 From: philk5pc@tyler.net (Phil Clements) Date: Fri, 5 Oct 2001 13:29:50 -0500 Subject: [AMPS] ALPHA 374A References: Message-ID: <000d01c14dcb$b8c98940$1e084c42@phil> Was there not also a "manual tune" 374? The 76 series also had various numbers of tubes, depending on model #. (((73))) Phil, K5PC > Not my 374A! Hmmmm...it's possible they changed something during the > multi-year sales cycle of this product, but the "374" meant "3 x 8874" and > used 3 tubes -- at least mine does. They also had a "274" which was "2 x > 8874" and used two tubes. Mine exhausts out the rear, exclusively. There's > no holes in the top, at all. > > WB2WIK/6 > > I think you are mistaken ... the 374A does exhaust out the top ... has 2 > > tubes ... no bandpass mode on 10 meters. > > Terry W6RU -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From tkass@forpsych.org Fri Oct 5 18:56:28 2001 From: tkass@forpsych.org (Tim Kass) Date: Fri, 5 Oct 2001 13:56:28 -0400 Subject: [AMPS] ALPHA 374A Message-ID: <01754BAF2339D311BBB200A0CC3E638003BB94@CFPBDC> The 374 has 2 8874, as does the 274, but added 160 meters on it, where the 274 did not....the 374A came later... 73 Tim -----Original Message----- From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On Behalf Of Steve Katz Sent: Friday, October 05, 2001 12:44 PM To: 'Terry Gaiser'; 'Bill Smith'; amps@contesting.com Subject: RE: [AMPS] ALPHA 374A Not my 374A! Hmmmm...it's possible they changed something during the multi-year sales cycle of this product, but the "374" meant "3 x 8874" and used 3 tubes -- at least mine does. They also had a "274" which was "2 x 8874" and used two tubes. Mine exhausts out the rear, exclusively. There's no holes in the top, at all. WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Terry Gaiser [SMTP:w6ru@bak.rr.com] > Sent: Friday, October 05, 2001 8:36 AM > To: Steve Katz; 'Bill Smith'; amps@contesting.com > Subject: Re: [AMPS] ALPHA 374A > > I think you are mistaken ... the 374A does exhaust out the top ... has 2 > tubes ... no bandpass mode on 10 meters. > Terry W6RU > > ----- Original Message ----- > From: Steve Katz > To: 'Bill Smith' ; > Sent: Friday, October 05, 2001 7:22 AM > Subject: RE: [AMPS] ALPHA 374A > > > > > > I purchased a 374A in "mint" condition a few years ago for $1295, and > felt > > that was a reasonably good deal. Obviously, the cost of three new > > replacement tubes is about that! For one with very few hours on the > tubes > > and in factory-fresh condition, I'd have likely paid a bit more. > > > > When you say "full output," is that in the bandpass (no-tune) mode? If > so, > > and you get full output on 10m in the bandpass mode, that's wonderful, > and > > unusual for such an oldie, probably means the owner never messed with > it! > > > > Only caveat I can think of is that the 374A needs to be installed where > > there's a lot of breathing room behind it. It does not vent or exhaust > out > > the top, but out the rear, and the output duct is very small (as you've > > likely noticed) and blows a steady stream of very hot air under key-down > > condx. That air needs to blow, unrestricted, for quite a distance. I > > wouldn't place anything behind the amp for about 12" or so. Other than > > that, it's a rather amazing amp that has proven itself a workhorse in > > hundreds of contest stations around the world... > > > > WB2WIK/6 > > > > "Each success only buys an admission ticket to a more difficult > problem." -- > > Henry Kissinger > > > > > -----Original Message----- > > > From: Bill Smith [SMTP:ko4nrbs@yahoo.com] > > > Sent: Thursday, October 04, 2001 7:08 PM > > > To: amps@contesting.com > > > Subject: [AMPS] ALPHA 374A > > > > > > > > > I've found a Alpha 374A amplifier that has not been > > > used for several years. The guy says he'll sell it > > > but does not know what it may be worth. It is in very > > > clean condition and when checked out today had full > > > output. It is in orginial condition with no mods. > > > It's pretty obvious this amp has not been used much!! > > > There isn't a scratch on it anywhere. > > > > > > What is a fair market price for this amp? Does the > > > Alpha 374A have a good reputation? > > > 73, > > > Bill Smith KO4NR > > > > > > ===== > > > Bill Smith KO4NR > > > > > > -- > > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > > Submissions: amps@contesting.com > > > Administrative requests: amps-REQUEST@contesting.com > > > Problems: owner-amps@contesting.com > > > > -- > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > Submissions: amps@contesting.com > > Administrative requests: amps-REQUEST@contesting.com > > Problems: owner-amps@contesting.com > > > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From paulc@mediaone.net Fri Oct 5 19:43:21 2001 From: paulc@mediaone.net (Paul Christensen) Date: Fri, 5 Oct 2001 14:43:21 -0400 Subject: [AMPS] ALPHA 374A References: <01754BAF2339D311BBB200A0CC3E638003BB94@CFPBDC> Message-ID: <015a01c14dcd$9cbf4620$6401a8c0@paulch> Looks like the 374 was produced with three 8874s and two with the 374A. See the following link for a complete listing of legacy Alpha Amplifier specs... http://www.alpha-amps.com/html/legacy.htm For those intersted, detailed pictures of my vapor-cooled Alpha PA70-V are also listed on this page. Click on the "70-V" model number for the images. 73, -Paul, W9AC ----- Original Message ----- From: "Tim Kass" To: "'Steve Katz'" ; "'Terry Gaiser'" ; "'Bill Smith'" ; Sent: Friday, October 05, 2001 1:56 PM Subject: RE: [AMPS] ALPHA 374A > > The 374 has 2 8874, as does the 274, but added 160 meters on it, where the > 274 did not....the 374A came later... 73 Tim > > > > > > -----Original Message----- > From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On > Behalf Of Steve Katz > Sent: Friday, October 05, 2001 12:44 PM > To: 'Terry Gaiser'; 'Bill Smith'; amps@contesting.com > Subject: RE: [AMPS] ALPHA 374A > > > > Not my 374A! Hmmmm...it's possible they changed something during the > multi-year sales cycle of this product, but the "374" meant "3 x 8874" and > used 3 tubes -- at least mine does. They also had a "274" which was "2 x > 8874" and used two tubes. Mine exhausts out the rear, exclusively. There's > no holes in the top, at all. > > WB2WIK/6 > > "Each success only buys an admission ticket to a more difficult problem." -- > Henry Kissinger > > > -----Original Message----- > > From: Terry Gaiser [SMTP:w6ru@bak.rr.com] > > Sent: Friday, October 05, 2001 8:36 AM > > To: Steve Katz; 'Bill Smith'; amps@contesting.com > > Subject: Re: [AMPS] ALPHA 374A > > > > I think you are mistaken ... the 374A does exhaust out the top ... has 2 > > tubes ... no bandpass mode on 10 meters. > > Terry W6RU > > > > ----- Original Message ----- > > From: Steve Katz > > To: 'Bill Smith' ; > > Sent: Friday, October 05, 2001 7:22 AM > > Subject: RE: [AMPS] ALPHA 374A > > > > > > > > > > I purchased a 374A in "mint" condition a few years ago for $1295, and > > felt > > > that was a reasonably good deal. Obviously, the cost of three new > > > replacement tubes is about that! For one with very few hours on the > > tubes > > > and in factory-fresh condition, I'd have likely paid a bit more. > > > > > > When you say "full output," is that in the bandpass (no-tune) mode? If > > so, > > > and you get full output on 10m in the bandpass mode, that's wonderful, > > and > > > unusual for such an oldie, probably means the owner never messed with > > it! > > > > > > Only caveat I can think of is that the 374A needs to be installed where > > > there's a lot of breathing room behind it. It does not vent or exhaust > > out > > > the top, but out the rear, and the output duct is very small (as you've > > > likely noticed) and blows a steady stream of very hot air under key-down > > > condx. That air needs to blow, unrestricted, for quite a distance. I > > > wouldn't place anything behind the amp for about 12" or so. Other than > > > that, it's a rather amazing amp that has proven itself a workhorse in > > > hundreds of contest stations around the world... > > > > > > WB2WIK/6 > > > > > > "Each success only buys an admission ticket to a more difficult > > problem." -- > > > Henry Kissinger > > > > > > > -----Original Message----- > > > > From: Bill Smith [SMTP:ko4nrbs@yahoo.com] > > > > Sent: Thursday, October 04, 2001 7:08 PM > > > > To: amps@contesting.com > > > > Subject: [AMPS] ALPHA 374A > > > > > > > > > > > > I've found a Alpha 374A amplifier that has not been > > > > used for several years. The guy says he'll sell it > > > > but does not know what it may be worth. It is in very > > > > clean condition and when checked out today had full > > > > output. It is in orginial condition with no mods. > > > > It's pretty obvious this amp has not been used much!! > > > > There isn't a scratch on it anywhere. > > > > > > > > What is a fair market price for this amp? Does the > > > > Alpha 374A have a good reputation? > > > > 73, > > > > Bill Smith KO4NR > > > > > > > > ===== > > > > Bill Smith KO4NR > > > > > > > > -- > > > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > > > Submissions: amps@contesting.com > > > > Administrative requests: amps-REQUEST@contesting.com > > > > Problems: owner-amps@contesting.com > > > > > > -- > > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > > Submissions: amps@contesting.com > > > Administrative requests: amps-REQUEST@contesting.com > > > Problems: owner-amps@contesting.com > > > > > > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w2ge@home.com Fri Oct 5 19:46:08 2001 From: w2ge@home.com (Phil Levin W2GE) Date: Fri, 5 Oct 2001 14:46:08 -0400 Subject: [AMPS] GS-35B HF Schematic Message-ID: I could swear there is some schematics drawn up using the Russian GS-35B for HF somewhere in cyberland???? Any help or ideas??? Thanks in advance, Phil W2GE -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Fri Oct 5 19:43:59 2001 From: stevek@jmr.com (Steve Katz) Date: Fri, 5 Oct 2001 11:43:59 -0700 Subject: [AMPS] ALPHA 374A Message-ID: Hi Paul, After dismantling and inspecting a 70V many years ago, I built a six meter water-cooled amp using the 3CV1500, a quart of D-I water and a surplus transmission cooler with a muffin fan...seriously. Darn, those amps run cool. Wish I still had it. Steve WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Paul Christensen [SMTP:paulc@mediaone.net] > Sent: Friday, October 05, 2001 11:43 AM > To: Tim Kass; Steve Katz; 'Terry Gaiser'; 'Bill Smith'; > amps@contesting.com > Subject: Re: [AMPS] ALPHA 374A > > Looks like the 374 was produced with three 8874s and two with the 374A. > See the following link for a complete listing of legacy > Alpha Amplifier specs... > > http://www.alpha-amps.com/html/legacy.htm > > For those intersted, detailed pictures of my vapor-cooled Alpha PA70-V are > also listed on this page. Click on the "70-V" model > number for the images. > > 73, > > -Paul, W9AC > > ----- Original Message ----- > From: "Tim Kass" > To: "'Steve Katz'" ; "'Terry Gaiser'" ; > "'Bill Smith'" ; > Sent: Friday, October 05, 2001 1:56 PM > Subject: RE: [AMPS] ALPHA 374A > > > > > > The 374 has 2 8874, as does the 274, but added 160 meters on it, where > the > > 274 did not....the 374A came later... 73 Tim > > > > > > > > > > > > -----Original Message----- > > From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On > > Behalf Of Steve Katz > > Sent: Friday, October 05, 2001 12:44 PM > > To: 'Terry Gaiser'; 'Bill Smith'; amps@contesting.com > > Subject: RE: [AMPS] ALPHA 374A > > > > > > > > Not my 374A! Hmmmm...it's possible they changed something during the > > multi-year sales cycle of this product, but the "374" meant "3 x 8874" > and > > used 3 tubes -- at least mine does. They also had a "274" which was "2 > x > > 8874" and used two tubes. Mine exhausts out the rear, exclusively. > There's > > no holes in the top, at all. > > > > WB2WIK/6 > > > > "Each success only buys an admission ticket to a more difficult > problem." -- > > Henry Kissinger > > > > > -----Original Message----- > > > From: Terry Gaiser [SMTP:w6ru@bak.rr.com] > > > Sent: Friday, October 05, 2001 8:36 AM > > > To: Steve Katz; 'Bill Smith'; amps@contesting.com > > > Subject: Re: [AMPS] ALPHA 374A > > > > > > I think you are mistaken ... the 374A does exhaust out the top ... has > 2 > > > tubes ... no bandpass mode on 10 meters. > > > Terry W6RU > > > > > > ----- Original Message ----- > > > From: Steve Katz > > > To: 'Bill Smith' ; > > > Sent: Friday, October 05, 2001 7:22 AM > > > Subject: RE: [AMPS] ALPHA 374A > > > > > > > > > > > > > > I purchased a 374A in "mint" condition a few years ago for $1295, > and > > > felt > > > > that was a reasonably good deal. Obviously, the cost of three new > > > > replacement tubes is about that! For one with very few hours on the > > > tubes > > > > and in factory-fresh condition, I'd have likely paid a bit more. > > > > > > > > When you say "full output," is that in the bandpass (no-tune) mode? > If > > > so, > > > > and you get full output on 10m in the bandpass mode, that's > wonderful, > > > and > > > > unusual for such an oldie, probably means the owner never messed > with > > > it! > > > > > > > > Only caveat I can think of is that the 374A needs to be installed > where > > > > there's a lot of breathing room behind it. It does not vent or > exhaust > > > out > > > > the top, but out the rear, and the output duct is very small (as > you've > > > > likely noticed) and blows a steady stream of very hot air under > key-down > > > > condx. That air needs to blow, unrestricted, for quite a distance. > I > > > > wouldn't place anything behind the amp for about 12" or so. Other > than > > > > that, it's a rather amazing amp that has proven itself a workhorse > in > > > > hundreds of contest stations around the world... > > > > > > > > WB2WIK/6 > > > > > > > > "Each success only buys an admission ticket to a more difficult > > > problem." -- > > > > Henry Kissinger > > > > > > > > > -----Original Message----- > > > > > From: Bill Smith [SMTP:ko4nrbs@yahoo.com] > > > > > Sent: Thursday, October 04, 2001 7:08 PM > > > > > To: amps@contesting.com > > > > > Subject: [AMPS] ALPHA 374A > > > > > > > > > > > > > > > I've found a Alpha 374A amplifier that has not been > > > > > used for several years. The guy says he'll sell it > > > > > but does not know what it may be worth. It is in very > > > > > clean condition and when checked out today had full > > > > > output. It is in orginial condition with no mods. > > > > > It's pretty obvious this amp has not been used much!! > > > > > There isn't a scratch on it anywhere. > > > > > > > > > > What is a fair market price for this amp? Does the > > > > > Alpha 374A have a good reputation? > > > > > 73, > > > > > Bill Smith KO4NR > > > > > > > > > > ===== > > > > > Bill Smith KO4NR > > > > > > > > > > -- > > > > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > > > > Submissions: amps@contesting.com > > > > > Administrative requests: amps-REQUEST@contesting.com > > > > > Problems: owner-amps@contesting.com > > > > > > > > -- > > > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > > > Submissions: amps@contesting.com > > > > Administrative requests: amps-REQUEST@contesting.com > > > > Problems: owner-amps@contesting.com > > > > > > > > > > > > -- > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > Submissions: amps@contesting.com > > Administrative requests: amps-REQUEST@contesting.com > > Problems: owner-amps@contesting.com > > > > > > -- > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > Submissions: amps@contesting.com > > Administrative requests: amps-REQUEST@contesting.com > > Problems: owner-amps@contesting.com > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k8cpa@arrl.net Fri Oct 5 19:54:31 2001 From: k8cpa@arrl.net (chuck) Date: Fri, 05 Oct 2001 14:54:31 -0400 Subject: [AMPS] Message-ID: <3.0.6.32.20011005145431.0083dc20@pop3.norton.antivirus> >// An example, please. Your Website for starters. I contacted the ARRL and asked about the contents of your site.. and They told me...."Consider the source" 73 -Chuck Adkins K8CPA Drummer, Guitar Player, Ham Radio, Jesus Freak Type Person at Large http://www.qsl.net/k8cpa k8cpa@arrl.net ---------------------------------------------------- Sign Up for NetZero Platinum Today Only $9.95 per month! http://my.netzero.net/s/signup?r=platinum&refcd=PT97 -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 5 19:59:33 2001 From: 2@vc.net (2) Date: Fri, 5 Oct 2001 11:59:33 -0700 Subject: [AMPS] vom check of 3-500Z tubes Message-ID: <200110051859.f95IxXZ29158@contesting.com> > >Jim Spears" said: >> >> > >> >> my amp supply lk-500 zb did a funny thing a while back when I powered >> >> it up after a long time in the closet and a cross country move. so >> >> far I have found a blown 1 ohm, 5 watt wire wound resistor. it was in >> >> two pieces so there is little debate on whether or not it blew... > >I am one of the least experienced amplifier debuggers on the reflector >having >only debugged and repaired five HF amplifiers (some more than once due to >severe contest quest-op abuse). I have spent a great deal of time however >troubleshooting other electronic things in my career. > >I try to start with an open mind to the problem. Root cause determination is a >methodical process. Analyze the failure and then take the simplest and least >expensive steps first working toward the more expensive and exotic. In this >case DC check the tubes, look for obvious arcing or a discharge path, inspect >and measure critical components in the path. Then replace the resistor and try >again! Dust, bugs, errant shards of solder, etc. could surely trigger the >disappearing glitch resistor trick. Doesn't it make sense after following the >steps above to just replace the resistor and fire the rig up again? Then take >the next step. > >I stand ready to be corrected! > // Such is a good approach. My experiences suggest that when a component blows, there is a chance that it wasn't because the component was defective. In other words, something else could have made it blow. For example, replacing a blown fuse seldom fixes the problem unless one investigates and finds out Why the fuse blew. - A blown glitch resistor means that the manufacturer may not have performed the necessary short B+ to gnd test. cheers, Ron - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 5 20:15:18 2001 From: 2@vc.net (2) Date: Fri, 5 Oct 2001 12:15:18 -0700 Subject: [AMPS] Message-ID: <200110051915.f95JFIZ29644@contesting.com> >>// An example, please. > >Your Website for starters. > >I contacted the ARRL and asked about the contents of your site.. and They >told me...."Consider the source" > // Hows about a specific example, Chuck? tnx - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ly3nml@centras.lt Fri Oct 5 19:36:02 2001 From: ly3nml@centras.lt (Gintaras) Date: Fri, 5 Oct 2001 21:36:02 +0300 Subject: [AMPS] GS-35B HF Schematic References: Message-ID: <001b01c14dcc$986e09e0$0203010a@Gintaras> > I could swear there is some schematics drawn up using the Russian GS-35B for > HF somewhere in cyberland???? > > > Any help or ideas??? Thanks in advance, Phil W2GE > http://ly1dq.hypermart.net/e_gs-35b.htm -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From salers@hamal.freemail.ne.jp Fri Oct 5 22:32:03 2001 From: salers@hamal.freemail.ne.jp (Xu) Date: Sat, 6 Oct 2001 05:32:03 +0800 Subject: [AMPS] Fan Message-ID: <007c01c14de5$2e9d6100$ba775dd3@8163> Hi! I have many square fans,some of them are in 220AC,some of them in DC12V,could some tell me how to cauculate the LPM(litre per minute) depone on the current of 220V AC and DC12V?I have a pair 30W AC Fan,can use in a Chinese FU-100F(4CX1000)?I have a Chinese Military 1.6KW HF SSB transmitter(use a FU-100F),but origional fan is to noisy. 73! de Xu -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Fri Oct 5 22:31:14 2001 From: stevek@jmr.com (Steve Katz) Date: Fri, 5 Oct 2001 14:31:14 -0700 Subject: [AMPS] Fan Message-ID: Xu, air flow volume is not based on voltage or current, but on cross-section, blade pitch and design, and rotational speed. Most all fans have a label indicating the manufacturer and model number; it's usually best to contact them for a full data sheet. Usually the sheet will include plots of air volume vs. back pressure, which is important to know when cooling an external anode tube. WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Xu [SMTP:salers@hamal.freemail.ne.jp] > Sent: Friday, October 05, 2001 2:32 PM > To: amps@contesting.com > Cc: homebrew@qth.net > Subject: [AMPS] Fan > > > Hi! > I have many square fans,some of them are in 220AC,some of them in > DC12V,could some tell me how to cauculate the LPM(litre per minute) depone > on the current of 220V AC and DC12V?I have a pair 30W AC Fan,can use in a > Chinese FU-100F(4CX1000)?I have a Chinese Military 1.6KW HF SSB > transmitter(use a FU-100F),but origional fan is to noisy. > 73! de Xu > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From salers@hamal.freemail.ne.jp Fri Oct 5 22:41:18 2001 From: salers@hamal.freemail.ne.jp (Xu) Date: Sat, 6 Oct 2001 05:41:18 +0800 Subject: [AMPS] Fan->make correct and 8877 vs GS35 References: <007c01c14de5$2e9d6100$ba775dd3@8163> Message-ID: <000c01c14de7$a4ec0580$01785dd3@8163> Hi! I have many square fans,some of them for 220AC,some of them for DC12V,could someone tell me how to cauculate the LPM(litre per minute) depend on the current of 220V AC and DC12V?I have a pair 30W AC Fan,can use in a Chinese FU-100F(4CX1000)?I have a Chinese Military 1.6KW HF SSB transmitter(use a FU-100F),but origional fan is too noisy.ps what diffrent between GS35 and 8877? 73! de Xu -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ve6xt@hotmail.com Fri Oct 5 23:10:19 2001 From: ve6xt@hotmail.com (John Kirk) Date: Fri, 05 Oct 2001 22:10:19 +0000 Subject: [AMPS] Re: [HomeBrew] Fan->make correct and 8877 vs GS35 Message-ID: Hi Xu: In general, the square "muffin" fans will be inadequate for cooling large external anode tubes. The type you want to look for are known as "squirrel cage" because they have inside, a round blade assembly that looks like those things that caged hamsters and rats exercise on. Even with them, I don't think power consumption equates real well to air movement - best to try to dig up the manufacturers specs, or conduct a test. I think G3SEK's website and books have some material on how to measure air flow. Good luck! John VK2PV >From: "Xu" >To: >CC: >Subject: [HomeBrew] Fan->make correct and 8877 vs GS35 >Date: Sat, 6 Oct 2001 05:41:18 +0800 > > > > > Hi! > I have many square fans,some of them for 220AC,some of them for >DC12V,could someone tell me how to cauculate the LPM(litre per minute) >depend > on the current of 220V AC and DC12V?I have a pair 30W AC Fan,can use in a > Chinese FU-100F(4CX1000)?I have a Chinese Military 1.6KW HF SSB > transmitter(use a FU-100F),but origional fan is too noisy.ps what >diffrent >between > GS35 and 8877? > > 73! de Xu > > > >---- >Submissions: homebrew@qth.net _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From kd4lyh@earthlink.net Sat Oct 6 01:11:10 2001 From: kd4lyh@earthlink.net (KD4LYH) Date: Fri, 5 Oct 2001 20:11:10 -0400 Subject: [AMPS] Tuned Input Circuit Q Message-ID: <001301c14dfb$68fe2260$ee482a3f@computer> This is a multi-part message in MIME format. ------=_NextPart_000_0010_01C14DD9.DFF67EC0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hello List members, Is there a formula for calculating tuned input circuit Q. I see a chart = in Bill Orr,s Handbook for various input impedances with Q,s of 2-3. Im = probably missing something here. How would you calculate for a tuned = input Q of 5. Im trying to learn so if its a dumb question I apologize = for my lack of experience. Is it roughly Rin/xc1? Im curious as how to = arrive at the values for a tuned input pi net for a given Q. 73,s Jeff ------=_NextPart_000_0010_01C14DD9.DFF67EC0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hello List members,

Is there a formula for calculating = tuned input=20 circuit Q. I see a chart in Bill Orr,s Handbook for various input = impedances=20 with Q,s of 2-3. Im probably missing something here. How would you = calculate for=20 a tuned input Q of 5. Im trying to learn so if its a dumb question I = apologize=20 for my lack of experience. Is it roughly Rin/xc1? Im curious as how to = arrive at=20 the values for a tuned input pi net for a given Q.

73,s Jeff
------=_NextPart_000_0010_01C14DD9.DFF67EC0-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Sat Oct 6 02:02:34 2001 From: W8JI@contesting.com (Tom Rauch) Date: Fri, 5 Oct 2001 21:02:34 -0400 Subject: [AMPS] Tuned Input Circuit Q In-Reply-To: <001301c14dfb$68fe2260$ee482a3f@computer> Message-ID: <3BBE1FEA.31278.2CA378EE@localhost> > Is there a formula for calculating tuned input circuit Q. I see a > chart in Bill Orr,s Handbook for various input impedances with Q,s of > 2-3. Im probably missing something here. How would you calculate for a > tuned input Q of 5. Im trying to learn so if its a dumb question I > apologize for my lack of experience. Is it roughly Rin/xc1? Im curious > as how to arrive at the values for a tuned input pi net for a given Q. > 73,s Jeff Hi Jeff, Most Handbooks use the Q of one end of the network as the Q, but that is actually incorrect. The actual Q involves all parts of the system. Eimac almost certainly is using the entire network's Q, rather than the Q at one end of the network. The nice thing is Q has very little effect on the system, it is fairly non-critical as long as the Q is more than 1+ the square root of the ratio of the impedances. Less than that and the network won't act like a pi. To behave like a pi, the network has to look like a step down and step up L network connected back to back. In other words, phase shift has to be somewhat more than 90 degrees and the impedance someplace in the network to ground has to be less than the lowest of the source and load impedances. In many cases I have looked at, the "simple Q" of two is nearly an overall Q of five. Orr and Eimac actually somewhat agree. Other than matching, which sets the minimum usable Q, the only other reason for a high input system Q is to provide a reasonably low shunt impedance for harmonics. That prevents the cathode of the tube from moving around at harmonics caused by the shorter than 360 degree conduction angle of the tube. Another thing is if any harmonics from the shorter than 360 degree conduction angle of the tube reach a solid state exciter, they can "fool" the SWR shutdown circuit into thinking the RF is being delivered to a mismatched load. Because of this, all input circuits should be a low pass C-L-C pi network or a parallel tuned network, and not any form of "T" or an L-C-L high-pass pi network. Fortunately Q is very non-critical in most applications, that is why so many approximations and rules-of-thumb work. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Sat Oct 6 02:37:38 2001 From: philk5pc@tyler.net (Phil Clements) Date: Fri, 5 Oct 2001 20:37:38 -0500 Subject: [AMPS] Tuned Input Circuit Q References: <3BBE1FEA.31278.2CA378EE@localhost> Message-ID: <000901c14e07$7c803880$ee084c42@phil> A nifty disk came with the 1996 ARRL Handbook. Among the programs is "pinet." I find this useful in starting out with a new design. You are asked to input R2, which is Rout, C(min), Q, and steps for calculating R1. I will let Tom et al decide if this is in the "ball park." I ran an R2 of 50 ohms, C(min) of 15 pf, and Q of 5. For 160 meters, I got : C1=4194 pf L=2.9 uh and C2=4194 pf. For a Q of 2, the above change to: C1=1678 pf L=4.2 uh and C2=1678 pf. "Free" software is sometimes worth what it costs, but it has worked for starters for me. (((73))) Phil, K5PC > > Is there a formula for calculating tuned input circuit Q. I see a > > chart in Bill Orr,s Handbook for various input impedances with Q,s of > > 2-3. Im probably missing something here. How would you calculate for a > > tuned input Q of 5. Im trying to learn so if its a dumb question I > > apologize for my lack of experience. Is it roughly Rin/xc1? Im curious > > as how to arrive at the values for a tuned input pi net for a given Q. > > 73,s Jeff -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Sat Oct 6 02:44:31 2001 From: philk5pc@tyler.net (Phil Clements) Date: Fri, 5 Oct 2001 20:44:31 -0500 Subject: [AMPS] Re: [amps] Fans and Henry Kissinger References: Message-ID: <001301c14e08$732e3ec0$ee084c42@phil> Subject: RE: [AMPS] Fan > > Xu, air flow volume is not based on voltage or current, but on > cross-section, blade pitch and design, and rotational speed. > > Most all fans have a label indicating the manufacturer and model number; > it's usually best to contact them for a full data sheet. Usually the sheet > will include plots of air volume vs. back pressure, which is important to > know when cooling an external anode tube. Nicely done, Steve! Thanks for helping Xu out. > "Each success only buys an admission ticket to a more difficult problem." -- > Henry Kissinger " Each failure usually buys an admission ticket to a more expensive solution." Phil Clements (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From salers@hamal.freemail.ne.jp Sat Oct 6 02:52:06 2001 From: salers@hamal.freemail.ne.jp (Xu) Date: Sat, 6 Oct 2001 09:52:06 +0800 Subject: [AMPS] Re FAN Message-ID: <001e01c14e09$82570de0$83775dd3@8163> Thanks for all reply. 73! Xu -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From wstarks@citynet.net Sat Oct 6 02:58:00 2001 From: wstarks@citynet.net (Bill Starks) Date: Fri, 5 Oct 2001 21:58:00 -0400 Subject: [AMPS] RF Concepts 2-417 amp Message-ID: Does anyone have a manual for the RF Concepts 2-417 amp that they will either sell or make a copy of it for me. I'll reinburse all costs. Bill K8WOS -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From rabella@mail.ilstu.edu Sat Oct 6 03:25:12 2001 From: rabella@mail.ilstu.edu (Ralph A. Bellas) Date: Fri, 05 Oct 2001 21:25:12 -0500 Subject: [AMPS] 4.7M resistors Message-ID: <3.0.3.32.20011005212512.00963100@mail.ilstu.edu> I'm looking for a half dozen of the 4.7 M 2W resistors that are used in the SB220 metering circuit. I am not sure what type should be used. There is about 1kv across them. Can anyone suggest a source for these? Thanks. Ralph K9ZO -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Wt8r@aol.com Sat Oct 6 04:29:44 2001 From: Wt8r@aol.com (Wt8r@aol.com) Date: Fri, 5 Oct 2001 23:29:44 EDT Subject: [AMPS] Message-ID: --part1_c3.1725e57d.28efd4a8_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 10/5/01 2:55:38 PM Eastern Daylight Time, k8cpa@arrl.net writes: > > >// An example, please. > > Your Website for starters. > > I contacted the ARRL and asked about the contents of your site.. and They > told me...."Consider the source" > > 73 > -Chuck Adkins K8CPA > Chuck, The source you refer to is the "ARRL" when you say consider the source, isn't it ? 73 de Dave, WT8R --part1_c3.1725e57d.28efd4a8_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 10/5/01 2:55:38 PM Eastern Daylight Time, k8cpa@arrl.net writes:

>// An example, please.

Your Website for starters.

I contacted the ARRL and asked about the contents of your site.. and They
told me...."Consider the source"

73
-Chuck Adkins K8CPA

Chuck,

The source you refer to is the "ARRL" when you say consider the source, isn't it ?

73 de

Dave, WT8R --part1_c3.1725e57d.28efd4a8_boundary-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From kb7ww@uswest.net Sat Oct 6 04:49:20 2001 From: kb7ww@uswest.net (Arthur Moe) Date: Sat, 06 Oct 2001 03:49:20 +0000 Subject: [AMPS] Tuned Input Circuit Q References: <3BBE1FEA.31278.2CA378EE@localhost> Message-ID: <3BBE7F40.2CB23396@uswest.net> Tom Rauch wrote: > Because of this, all input circuits should be a low pass C-L-C pi > network or a parallel tuned network, and not any form of "T" or an > L-C-L high-pass pi network. > > Tom or others, Could you please clarify the last of this statement "and not any form of "T" or an L-C-L high-pass pi network. In Bob Sutherland's W6Po 3cx1500 8877 144 and 220 mhz amplifiers ( http://web.wt.net/~w5un/8877-1.htm ) plus if I remember his call correctly W6ODV's 8877 50 mhz in Hamradio. And all of the 3cx800 3cx1500 Amplifiers in the ARRL hand book ALL use an L-C-L "T" input network. Don't want to start a argument just looking for information. Thanks Art KB7WW -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sat Oct 6 07:54:45 2001 From: 2@vc.net (2) Date: Fri, 5 Oct 2001 23:54:45 -0700 Subject: [AMPS] Tuned Input Circuit Q Message-ID: <200110060654.f966shZ11449@contesting.com> > > > >Tom Rauch wrote: > >> Because of this, all input circuits should be a low pass C-L-C pi >> network or a parallel tuned network, and not any form of "T" or an >> L-C-L high-pass pi network. >> >> > > Tom or others, >Could you please clarify the last of this statement "and not any form >of "T" or an L-C-L high-pass pi network. > >In Bob Sutherland's W6Po 3cx1500 8877 144 and 220 mhz amplifiers >( http://web.wt.net/~w5un/8877-1.htm ) plus if I remember his call >correctly W6ODV's 8877 50 mhz in Hamradio. And all of the 3cx800 >3cx1500 Amplifiers in the ARRL hand book ALL use an L-C-L "T" input >network. > >Don't want to start a argument just looking for information. > // The statement that "or a parallel tuned network" should be questioned. A parallel tuned input will work ok only when the Q requirement is met and the average cathode-Z is close to 50-ohms. cheers, Art - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sat Oct 6 07:54:48 2001 From: 2@vc.net (2) Date: Fri, 5 Oct 2001 23:54:48 -0700 Subject: [AMPS] Message-ID: <200110060654.f966skZ11454@contesting.com> >In a message dated 10/5/01 2:55:38 PM Eastern Daylight Time, k8cpa@arrl.net >writes: >> >> >// An example, please. >> >> Your Website for starters. >> >> I contacted the ARRL and asked about the contents of your site.. and They >> told me...."Consider the source" >> >> 73 >> -Chuck Adkins K8CPA >> > >Chuck, > >The source you refer to is the "ARRL" when you say consider the source, >isn't it ? > // Of, by and for amateur radio advertisers. . . > cheers, Dave - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sat Oct 6 07:54:50 2001 From: 2@vc.net (2) Date: Fri, 5 Oct 2001 23:54:50 -0700 Subject: [AMPS] Tuned Input Circuit Q Message-ID: <200110060654.f966snZ11459@contesting.com> >Hello List members, >Is there a formula for calculating tuned input circuit Q. I see a chart in >Bill Orr,s Handbook for various input impedances with Q,s of 2-3. Im >probably missing something here. How would you calculate for a tuned input >Q of 5. Im trying to learn so if its a dumb question I apologize for my >lack of experience. Is it roughly Rin/xc1? // Yes. However, Xc2 raises the Q a bit. If Xc1=15 - 25 ohms, it will quite likely produce a decent match for the transceiver. More Q =s a better flywheel. Less Q =s more bandwidth and not as good an SWR. > Im curious as how to arrive at >the values for a tuned input pi net for a given Q. // G-G tuned inputs are sorta like fishing bait. Whatever works is right. - cheers, Jeff > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sat Oct 6 07:54:52 2001 From: 2@vc.net (2) Date: Fri, 5 Oct 2001 23:54:52 -0700 Subject: [AMPS] Tuned Input Circuit Q Message-ID: <200110060654.f966spZ11466@contesting.com> > >> Is there a formula for calculating tuned input circuit Q. I see a >> chart in Bill Orr,s Handbook for various input impedances with Q,s of >> 2-3. Im probably missing something here. How would you calculate for a >> tuned input Q of 5. Im trying to learn so if its a dumb question I >> apologize for my lack of experience. Is it roughly Rin/xc1? Im curious >> as how to arrive at the values for a tuned input pi net for a given Q. >> 73,s Jeff > >Hi Jeff, > >Most Handbooks use the Q of one end of the network as the Q, but >that is actually incorrect. The actual Q involves all parts of the >system. > >Eimac almost certainly is using the entire network's Q, rather than >the Q at one end of the network. // Almost is undoubtedly right. In Care and Feeding, Eimac figures Q based on Xc1. > >The nice thing is Q has very little effect on the system, it is fairly >non-critical as long as the Q is more than 1+ the square root of the >ratio of the impedances. Less than that and the network won't act >like a pi. To behave like a pi, the network has to look like a step >down and step up L network connected back to back. In other >words, phase shift has to be somewhat more than 90 degrees and >the impedance someplace in the network to ground has to be less >than the lowest of the source and load impedances. > >In many cases I have looked at, the "simple Q" of two is nearly an >overall Q of five. Orr and Eimac actually somewhat agree. > >Other than matching, which sets the minimum usable Q, the only >other reason for a high input system Q is to provide a reasonably >low shunt impedance for harmonics. That prevents the cathode of >the tube from moving around at harmonics caused by the shorter >than 360 degree conduction angle of the tube. Another thing is if >any harmonics from the shorter than 360 degree conduction angle >of the tube reach a solid state exciter, they can "fool" the SWR >shutdown circuit into thinking the RF is being delivered to a >mismatched load. > >Because of this, all input circuits should be a low pass C-L-C pi >network or a parallel tuned network, and not any form of "T" or an >L-C-L high-pass pi network. > >Fortunately Q is very non-critical in most applications, // For g-g amplifiers with a tube-type Pi-net tuned output driver, this is undoubtedly true. With a solid-state untuned output, this is hardly the case. >that is why >so many approximations and rules-of-thumb work. >73, Tom W8JI - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Ian White, G3SEK" make correct and 8877 vs GS35 In-Reply-To: References: Message-ID: John Kirk wrote: > >Hi Xu: >In general, the square "muffin" fans will be inadequate for cooling large >external anode tubes. The type you want to look for are known as "squirrel >cage" because they have inside, a round blade assembly that looks like those >things that caged hamsters and rats exercise on. >Even with them, I don't think power consumption equates real well to air >movement - best to try to dig up the manufacturers specs, or conduct a test. >I think G3SEK's website and books have some material on how to measure air >flow. Nothing on the website or the "DX Book" but it's very simple: you time how long it takes for the outlet air to fully inflate a light plastic bag. The idea comes courtesy of George, K6GT. The volume of the bag can be a bit tricky. In Britain a standard kitchen swing-bin liner is 50-55 litres, but you can measure it by pouring water into the bag. (The really clever trick is to support the bag in a barrel of water while you're going it. The guy in GJ who told me that said he learned it from Archimedes.) The other slightly difficult bit is to work out how to start with the bag crushed almost flat, and whip it quickly over the output - because you have to make the whole measurement while the blower is already running at full speed. I usually tape two sides, and very quickly pull the other two sides tight around the case. With a bit of practice you can get repeatability better than 10% which is fine for this application. It's a very good idea to make a mock-up with the blower, the tube and the important parts of the air-flow circuit. 73 from Ian G3SEK Editor, 'The VHF/UHF DX Book' 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.com/g3sek -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Wt8r@aol.com Sat Oct 6 14:16:55 2001 From: Wt8r@aol.com (Wt8r@aol.com) Date: Sat, 6 Oct 2001 09:16:55 EDT Subject: [AMPS] Message-ID: --part1_d6.ca8595f.28f05e47_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 10/6/01 2:54:59 AM Eastern Daylight Time, 2@vc.net writes: > >In a message dated 10/5/01 2:55:38 PM Eastern Daylight Time, k8cpa@arrl.net > >writes: > >> > >> >// An example, please. > >> > >> Your Website for starters. > >> > >> I contacted the ARRL and asked about the contents of your site.. and They > >> told me...."Consider the source" > >> > >> 73 > >> -Chuck Adkins K8CPA > >> > > > >Chuck, > > > >The source you refer to is the "ARRL" when you say consider the source, > >isn't it ? > > > // Of, by and for amateur radio advertisers. . . > > > cheers, Dave > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. > end > Chuck, I would be interested in taking a look at your web site. Would please supply the URL to the list? 73 & have a great day, Dave, WT8R --part1_d6.ca8595f.28f05e47_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 10/6/01 2:54:59 AM Eastern Daylight Time, 2@vc.net writes:

>In a message dated 10/5/01 2:55:38 PM Eastern Daylight Time, k8cpa@arrl.net
>writes:
>>
>> >// An example, please.
>>
>> Your Website for starters.
>>
>> I contacted the ARRL and asked about the contents of your site.. and They
>> told me...."Consider the source"
>>
>> 73
>> -Chuck Adkins K8CPA
>>
>
>Chuck,
>
>The source you refer to is the "ARRL" when you say consider the source,
>isn't it ?
>
//   Of, by and for amateur radio advertisers. . .
>
cheers, Dave

- R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures.
end

Chuck,

I would be interested in taking a look at your web site. Would please supply the URL to the list?

73 & have a great day,

Dave, WT8R --part1_d6.ca8595f.28f05e47_boundary-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k8cpa@arrl.net Sat Oct 6 17:09:43 2001 From: k8cpa@arrl.net (chuck) Date: Sat, 06 Oct 2001 12:09:43 -0400 Subject: [AMPS] In-Reply-To: Message-ID: <3.0.6.32.20011006120943.0082ea80@pop3.norton.antivirus> At 11:29 PM 10/5/2001 EDT, you wrote: >In a message dated 10/5/01 2:55:38 PM Eastern Daylight Time, k8cpa@arrl.net >writes: > >> > >Your Website for starters. > >I contacted the ARRL and asked about the contents of your site.. and They >told me...."Consider the source" > >73 > K8CPA > > > >Chuck, > >The source you refer to is the "ARRL" when you say consider the source, >isn't it ? > >73 de > >Dave, WT8R Nope. I'm referring to Rich Measures's Site... full of Half truths and Outright Lies. and let me give you fair warning... one more harrashing e-mail to my e-mail address and you will be hearing from my attorney. Don't bite more than you can chew. 73 -Chuck Adkins K8CPA Drummer, Guitar Player, Ham Radio, Jesus Freak Type Person at Large http://www.qsl.net/k8cpa k8cpa@arrl.net ---------------------------------------------------- Sign Up for NetZero Platinum Today Only $9.95 per month! http://my.netzero.net/s/signup?r=platinum&refcd=PT97 -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k8cpa@arrl.net Sat Oct 6 17:12:47 2001 From: k8cpa@arrl.net (chuck) Date: Sat, 06 Oct 2001 12:12:47 -0400 Subject: [AMPS] In-Reply-To: Message-ID: <3.0.6.32.20011006121247.0083e770@pop3.norton.antivirus> At 09:16 AM 10/6/2001 EDT, you wrote: >In a message dated 10/6/01 2:54:59 AM Eastern Daylight Time, 2@vc.net writes: > > >>In a message dated 10/5/01 2:55:38 PM Eastern Daylight Time, k8cpa@arrl.net >>writes: >>> >>>> >>> >>> Your Website for starters. >>> >>> I contacted the ARRL and asked about the contents of your site.. and They >>> told me...."Consider the source" >>> >>> 73 >>> K8CPA >>> >> >>Chuck, >> >>The source you refer to is the "ARRL" when you say consider the source, >>isn't it ? >> > advertisers. . . >> >cheers, Dave > > >end > > > >Chuck, > > Would please supply the URL to the list? > >& have a great day, > >Dave, WT8R I wouldn't give you the lent between my toes, asshole. -Chuck Adkins K8CPA Drummer, Guitar Player, Ham Radio, Jesus Freak Type Person at Large http://www.qsl.net/k8cpa k8cpa@arrl.net ---------------------------------------------------- Sign Up for NetZero Platinum Today Only $9.95 per month! http://my.netzero.net/s/signup?r=platinum&refcd=PT97 -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sat Oct 6 17:23:16 2001 From: 2@vc.net (2) Date: Sat, 6 Oct 2001 09:23:16 -0700 Subject: [AMPS] Message-ID: <200110061623.f96GNDZ19401@contesting.com> >In a message dated 10/6/01 2:54:59 AM Eastern Daylight Time, 2@vc.net writes: > > >> >In a message dated 10/5/01 2:55:38 PM Eastern Daylight Time, k8cpa@arrl.net >> >writes: >> >> >> >> >// An example, please. >> >> >> >> Your Website for starters. >> >> >> >> I contacted the ARRL and asked about the contents of your site.. and They >> >> told me...."Consider the source" >> >> >> >> 73 >> >> -Chuck Adkins K8CPA >> >> >> > >> >Chuck, >> > >> >The source you refer to is the "ARRL" when you say consider the source, >> >isn't it ? >> > >> // Of, by and for amateur radio advertisers. . . >> > >> cheers, Dave >> >> - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. >> end >> > >Chuck, > >I would be interested in taking a look at your web site. Would please >supply >the URL to the list? > // the URL is in my signature line. > cheers, Dave - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k8cpa@arrl.net Sat Oct 6 17:34:51 2001 From: k8cpa@arrl.net (chuck) Date: Sat, 06 Oct 2001 12:34:51 -0400 Subject: [AMPS] In-Reply-To: <200110061623.f96GNDZ19401@contesting.com> Message-ID: <3.0.6.32.20011006123451.0083ed20@pop3.norton.antivirus> >> >// the URL is in my signature line. Okay... Here's what I got to say..... I am dropping the thread.... I am not interested in a catfight over my personal opinions of Rich... it's obvious that WT8R wants a cat fight... and I'm not about to start a shooting match in a e-mail reflector... Rich's opinion is just that... His.. and I respect that... To Rich... I don't always agree with you. But Sometimes... Once and a while, you do say some things I agree with... But I'm not gonna do any mud slinging in this reflector... it's just not worth the effort. To WT8R: You say you're a "Real" Extra Class Operator? BIG DEAL, you took a code test. What does that make you? A Ham that can copy fast CW. That's all nothing else. If you think that copying CW at 20 WPM makes you a better ham, More power to you. If that's what it takes to stroke your oversized Ego..More power to you... Just remember the Coast Guard Stopped using CW years ago... But I'm not interested in a debate, nor in mud slinging... Anyhow... let's get back to what this Mailing list is all about... AMPS! Thanks Rich. -Chuck K8CPA A "REAL" General Class Amateur Radio Operator. -Chuck Adkins K8CPA Drummer, Guitar Player, Ham Radio, Jesus Freak Type Person at Large http://www.qsl.net/k8cpa k8cpa@arrl.net ---------------------------------------------------- Sign Up for NetZero Platinum Today Only $9.95 per month! http://my.netzero.net/s/signup?r=platinum&refcd=PT97 -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sat Oct 6 17:39:27 2001 From: 2@vc.net (2) Date: Sat, 6 Oct 2001 09:39:27 -0700 Subject: [AMPS] Message-ID: <200110061639.f96GdOZ19786@contesting.com> > >At 09:16 AM 10/6/2001 EDT, you wrote: >>In a message dated 10/6/01 2:54:59 AM Eastern Daylight Time, 2@vc.net >writes: >> >> >>>In a message dated 10/5/01 2:55:38 PM Eastern Daylight Time, >k8cpa@arrl.net >>>writes: >>>> >>>>> >>>> >>>> Your Website for starters. >>>> >>>> I contacted the ARRL and asked about the contents of your site.. and They >>>> told me...."Consider the source" >>>> >>>> 73 >>>> K8CPA >>>> >>> >>>Chuck, >>> >>>The source you refer to is the "ARRL" when you say consider the source, >>>isn't it ? >>> >> advertisers. . . >>> >>cheers, Dave >> >> >>end >> >> >> >>Chuck, >> >> Would please supply the URL to the list? >> >>& have a great day, >> >>Dave, WT8R > >I wouldn't give you the lent between my toes, asshole. > // Chuck must have unusually big feet to squeeze the 40 weekdays from Ash Wednesday until Easter between his toes. >Drummer, Guitar Player, Ham Radio, Jesus Freak Type Person at Large >http://www.qsl.net/k8cpa >k8cpa@arrl.net > > >---------------------------------------------------- >Sign Up for NetZero Platinum Today >Only $9.95 per month! >http://my.netzero.net/s/signup?r=platinum&refcd=PT97 > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sat Oct 6 17:39:30 2001 From: 2@vc.net (2) Date: Sat, 6 Oct 2001 09:39:30 -0700 Subject: [AMPS] Message-ID: <200110061639.f96GdRZ19790@contesting.com> > >At 11:29 PM 10/5/2001 EDT, you wrote: >>In a message dated 10/5/01 2:55:38 PM Eastern Daylight Time, k8cpa@arrl.net >>writes: >> >>> >> >>Your Website for starters. >> >>I contacted the ARRL and asked about the contents of your site.. and They >>told me...."Consider the source" >> >>73 >> K8CPA >> >> >> >>Chuck, >> >>The source you refer to is the "ARRL" when you say consider the source, >>isn't it ? >> >>73 de >> >>Dave, WT8R > >Nope. I'm referring to Rich Measures's Site... full of Half truths and >Outright Lies. and let me give you fair warning... one more harrashing >e-mail to my e-mail address and you will be hearing from my attorney. > >Don't bite more than you can chew. > // Remember kids, just say no to drugs. > > >-Chuck Adkins K8CPA >Drummer, Guitar Player, Ham Radio, Jesus Freak Type Person at Large >http://www.qsl.net/k8cpa >k8cpa@arrl.net > > >---------------------------------------------------- >Sign Up for NetZero Platinum Today >Only $9.95 per month! >http://my.netzero.net/s/signup?r=platinum&refcd=PT97 > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sat Oct 6 18:25:01 2001 From: 2@vc.net (2) Date: Sat, 6 Oct 2001 10:25:01 -0700 Subject: [AMPS] Message-ID: <200110061724.f96HOwZ20710@contesting.com> >>> >>// the URL is in my signature line. > > > >Okay... Here's what I got to say..... > >I am dropping the thread.... I am not interested in a catfight over my >personal opinions of Rich... it's obvious that WT8R wants a cat fight... >and I'm not about to start a shooting match in a e-mail reflector... Rich's >opinion is just that... His.. and I respect that... > >To Rich... I don't always agree with you. But Sometimes... Once and a >while, you do say some things I agree with... But I'm not gonna do any mud >slinging in this reflector... it's just not worth the effort. // Translation: My ammo box is beginning to look sorta empty. Free, unsolicited advise: 1. Playing the Anal Card is hardly good form. 2, Playing the Lies Card is not nearly as safe as discussing specific problem areas. In other words, the guy you accuse of lying may not be. 3. Threats are inevitably bad for the issuer. 4. Never let your opponent know when you get tight jaws. 5. Whenever possible, be the first to admit an error. cheers, Chuck >To WT8R: > >You say you're a "Real" Extra Class Operator? BIG DEAL, you took a code >test. What does that make you? A Ham that can copy fast CW. That's all >nothing else. If you think that copying CW at 20 WPM makes you a better >ham, More power to you. If that's what it takes to stroke your oversized >Ego..More power to you... Just remember the Coast Guard Stopped using CW >years ago... But I'm not interested in a debate, nor in mud slinging... > >Anyhow... let's get back to what this Mailing list is all about... > > >AMPS! > >Thanks Rich. > ur welcome >-Chuck K8CPA - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Wt8r@aol.com Sat Oct 6 20:40:32 2001 From: Wt8r@aol.com (Wt8r@aol.com) Date: Sat, 6 Oct 2001 15:40:32 EDT Subject: [AMPS] Message-ID: <7f.1b482e4f.28f0b830@aol.com> --part1_7f.1b482e4f.28f0b830_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Mike, I'm not sure about the "loving thy neighbor" part. Dave, WT8R ------------------------------------------------------------------------------ -------------------------------------------- In a message dated 10/6/01 1:11:58 PM Eastern Daylight Time, W4EF@dellroy.com writes: > Looks like Chuck gave up spelling and loving thy neighbor for lent. Or maybe > it just all the > haraSHment you guys have been giving him :) > > 73 de Mike, W4EF.......... > > > ----- Original Message ----- > From: "2" <2@vc.net> > To: "chuck" ; "Dave" > Cc: "AMPS" > Sent: Saturday, October 06, 2001 9:39 AM > Subject: Re: [AMPS] > > > > > > > > > >At 09:16 AM 10/6/2001 EDT, you wrote: > > >>In a message dated 10/6/01 2:54:59 AM Eastern Daylight Time, 2@vc.net > > >writes: > > >> > > >> > > >>>In a message dated 10/5/01 2:55:38 PM Eastern Daylight Time, > > >k8cpa@arrl.net > > >>>writes: > > >>>> > > >>>>> > > >>>> > > >>>> Your Website for starters. > > >>>> > > >>>> I contacted the ARRL and asked about the contents of your site.. and > They > > >>>> told me...."Consider the source" > > >>>> > > >>>> 73 > > >>>> K8CPA > > >>>> > > >>> > > >>>Chuck, > > >>> > > >>>The source you refer to is the "ARRL" when you say consider the > source, > > >>>isn't it ? > > >>> > > >> advertisers. . . > > >>> > > >>cheers, Dave > > >> > > >> > > >>end > > >> > > >> > > >> > > >>Chuck, > > >> > > >> Would please supply the URL to the list? > > >> > > >>& have a great day, > > >> > > >>Dave, WT8R > > > > > >I wouldn't give you the lent between my toes, asshole. > > > > > // Chuck must have unusually big feet to squeeze the 40 weekdays from > > Ash Wednesday until Easter between his toes. > > > > > > >Drummer, Guitar Player, Ham Radio, Jesus Freak Type Person at Large > > >http://www.qsl.net/k8cpa > > >k8cpa@arrl.net > > > > > > > > >---------------------------------------------------- > > >Sign Up for NetZero Platinum Today > > >Only $9.95 per month! > > >http://my.netzero.net/s/signup?r=platinum&refcd=PT97 > > > > > >-- > > >FAQ on WWW: http://www.contesting.com/FAQ/amps > > >Submissions: amps@contesting.com > > >Administrative requests: amps-REQUEST@contesting.com > > >Problems: owner-amps@contesting.com > > > > > > > > > > > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. > > end > > > > > > -- > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > Submissions: amps@contesting.com > > Administrative requests: amps-REQUEST@contesting.com > > Problems: owner-amps@contesting.com > > > --part1_7f.1b482e4f.28f0b830_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit Mike,

I'm not sure about the "loving thy neighbor" part.

Dave, WT8R
--------------------------------------------------------------------------------------------------------------------------

In a message dated 10/6/01 1:11:58 PM Eastern Daylight Time, W4EF@dellroy.com writes:

Looks like Chuck gave up spelling and loving thy neighbor for lent. Or maybe it just all the
haraSHment you guys have been giving him :)

73 de Mike, W4EF..........

----- Original Message -----
From: "2" <2@vc.net>
To: "chuck" <k8cpa@arrl.net>; "Dave" <Wt8r@aol.com>
Cc: "AMPS" <amps@contesting.com>
Sent: Saturday, October 06, 2001 9:39 AM
Subject: Re: [AMPS]

>
> >
> >At 09:16 AM 10/6/2001 EDT, you wrote:
> >>In a message dated 10/6/01 2:54:59 AM Eastern Daylight Time, 2@vc.net
> >writes:
> >>
> >>
> >>>In a message dated 10/5/01 2:55:38 PM Eastern Daylight Time,
> >k8cpa@arrl.net
> >>>writes:
> >>>>
> >>>>>
> >>>>
> >>>> Your Website for starters.
> >>>>
> >>>> I contacted the ARRL and asked about the contents of your site.. and They
> >>>> told me...."Consider the source"
> >>>>
> >>>> 73
> >>>> K8CPA
> >>>>
> >>>
> >>>Chuck,
> >>>
> >>>The source you refer to is the "ARRL" when you say consider the source,
> >>>isn't it ?
> >>>
> >>   advertisers. . .
> >>>
> >>cheers, Dave
> >>
> >>
> >>end
> >>
> >>
> >>
> >>Chuck,
> >>
> >> Would please supply the URL to the list?
> >>
> >>& have a great day,
> >>
> >>Dave, WT8R
> >
> >I wouldn't give you the lent between my toes, asshole.
> >
> // Chuck must have unusually big feet to squeeze the 40 weekdays from
> Ash Wednesday until Easter between his toes.
>
>
> >Drummer, Guitar Player, Ham Radio, Jesus Freak Type Person at Large
> >http://www.qsl.net/k8cpa
> >k8cpa@arrl.net
> >
> >
> >----------------------------------------------------
> >Sign Up for NetZero Platinum Today
> >Only $9.95 per month!
> >http://my.netzero.net/s/signup?r=platinum&refcd=PT97
> >
> >--
> >FAQ on WWW:               http://www.contesting.com/FAQ/amps
> >Submissions:              amps@contesting.com
> >Administrative requests: amps-REQUEST@contesting.com
> >Problems:                 owner-amps@contesting.com
> >
> >
>
>
> - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures.
> end
>
>
> --
> FAQ on WWW:               http://www.contesting.com/FAQ/amps
> Submissions:              amps@contesting.com
> Administrative requests: amps-REQUEST@contesting.com
> Problems:                 owner-amps@contesting.com
>

--part1_7f.1b482e4f.28f0b830_boundary-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ve3by@bmts.com Sat Oct 6 23:44:51 2001 From: ve3by@bmts.com (Carl & Kim Styan) Date: Sat, 6 Oct 2001 18:44:51 -0400 Subject: [AMPS] tube-6156 Message-ID: <014f01c14eb8$915c9f80$249eb7d8@ve3by> This is a multi-part message in MIME format. ------=_NextPart_000_014C_01C14E96.FB982E40 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Came across 3 - 6156 tubes during my basement clean up. they look like = a 4-400. Does anyone has a cross reference for this number. also found: 3X300A1 and a unused Econoco 3CX2500A3. If I remember the mu (20?) is much different from a 3CX3000A7. both use = the same coaxal socket as a 3CX3000A7. Are these good for SSB service. or land fill. 73 Carl ------=_NextPart_000_014C_01C14E96.FB982E40 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Came across 3 - 6156 tubes during my = basement=20 clean up. they look like a 4-400. Does anyone has a cross reference for = this=20 number.

also found:

3X300A1 and a unused Econoco = 3CX2500A3.

If I remember the mu (20?) is much = different from=20 a 3CX3000A7. both use the same coaxal socket as a = 3CX3000A7.

Are these good for SSB service. or land=20 fill.

73

Carl

------=_NextPart_000_014C_01C14E96.FB982E40-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ve3by@bmts.com Sat Oct 6 23:53:46 2001 From: ve3by@bmts.com (Carl & Kim Styan) Date: Sat, 6 Oct 2001 18:53:46 -0400 Subject: [AMPS] Fw: tube-6156 Message-ID: <017401c14eb9$c2172ea0$249eb7d8@ve3by> This is a multi-part message in MIME format. ------=_NextPart_000_0171_01C14E98.3A223380 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Correction on one of the tube numbers. 3X300A1 should read 3X3000A1. 73 Carl __________________________________________________________________ Came across 3 - 6156 tubes during my basement clean up. they look like = a 4-400. Does anyone has a cross reference for this number. =20 also found: 3X300A1 and a unused Econoco 3CX2500A3. If I remember the mu (20?) is much different from a 3CX3000A7. both use = the same coaxal socket as a 3CX3000A7. Are these good for SSB service. or land fill. =20 73 Carl =20 ------=_NextPart_000_0171_01C14E98.3A223380 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Correction on one of the tube numbers. = 3X300A1 should=20 read 3X3000A1.

73

Carl

_________________________________________________________= _________

Came across 3 - 6156 tubes during my = basement=20 clean up. they look like a 4-400. Does anyone has a cross reference for = this=20 number.

also found:

3X300A1 and a unused Econoco = 3CX2500A3.

If I remember the mu (20?) is much = different from=20 a 3CX3000A7. both use the same coaxal socket as a = 3CX3000A7.

Are these good for SSB service. or land=20 fill.

73

Carl

------=_NextPart_000_0171_01C14E98.3A223380-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jtml@lanl.gov Sun Oct 7 02:24:31 2001 From: jtml@lanl.gov (John Lyles) Date: Sat, 6 Oct 2001 19:24:31 -0600 Subject: [AMPS] WTB 51J4 In-Reply-To: <200110060345.f963jeZ08829@contesting.com> References: <200110060345.f963jeZ08829@contesting.com> Message-ID: Looking for Collins Radio 51J4 receiver, in gud shape. 6 kHz filter desired. John K5PRO -- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ko4nrbs@yahoo.com Sun Oct 7 04:43:05 2001 From: ko4nrbs@yahoo.com (Bill Smith) Date: Sat, 6 Oct 2001 20:43:05 -0700 (PDT) Subject: [AMPS] Finding the Q of a Coil Message-ID: <20011007034305.42803.qmail@web20501.mail.yahoo.com> Hung up trying to calculate the Q of a coil I want to build. It will be 2 inches in diameter with 26 turns of #10 wire. The length is 5.3 inches. 4.9 Turns per inch. HAMCALC computes this at 11uh of inductance. If I got it right Inductive Reactance of this coil on 10 meters= 2*3.14*29000000*.000011 or 2003 ohms Q of this coil should be the Inductive Reactance divided by the internal resistance of the coil's wire (factoring in the RF). This is where I got bogged down. Couldn't come up with an appropiate number. Where am I going wrong? 73, Bill ===== Bill Smith KO4NR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ve3by@bmts.com Sun Oct 7 04:52:21 2001 From: ve3by@bmts.com (Carl & Kim Styan) Date: Sat, 6 Oct 2001 23:52:21 -0400 Subject: [AMPS] Fw: tube-6156 Message-ID: <003401c14ee3$78b735a0$a09eb7d8@ve3by> This is a multi-part message in MIME format. ------=_NextPart_000_0031_01C14EC1.F0C23A80 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Thanks everone for the info. Marv the 6156 is made by Rogers, 36-56 is the date code. 73 Carl -----Original Message----- From: Radio WC6W To: ve3by@bmts.com Date: Saturday, October 06, 2001 11:25 PM Subject: Re: [AMPS] Fw: tube-6156 =20 =20 =20 On Sat, 6 Oct 2001 18:53:46 -0400 "Carl & Kim Styan" = writes: > >Correction on one of the tube numbers. 3X300A1 should read = 3X3000A1. >73 >Carl =20 Hi Carl, The 6156 is an old Amperex number for a premium 4-250A. May have = also been manufactured by Eimac later -- I'll bet whoever made it marked = it! =20 The A1 is only useful as an audio amp. The A3 may be used as = either an audio amp or a grid driven RF amp. Neither is suitable for = cathode driven service with their low =B5. Do you have any friend's who = want to build a big Tesla coil? =20 73, Marv WC6W =20 =20 =20 > > >Came across 3 - 6156 tubes during my basement clean up. they look=20 >like =3D >a 4-400. Does anyone has a cross reference for this number. >=3D20 >also found: >3X300A1 and a unused Econoco 3CX2500A3. >If I remember the mu (20?) is much different from a 3CX3000A7. = both=20 >use =3D >the same coaxal socket as a 3CX3000A7. >Are these good for SSB service. or land fill. >=3D20 >73 >Carl >=3D20 > =20 ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. ------=_NextPart_000_0031_01C14EC1.F0C23A80 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Thanks everone for the info.

Marv the 6156 is made by Rogers, 36-56 = is the=20 date code.

73

Carl

-----Original = Message-----
From:=20 Radio WC6W <wc6w@juno.com>
To: ve3by@bmts.com <ve3by@bmts.com>
Date:=20 Saturday, October 06, 2001 11:25 PM
Subject: Re: = [AMPS] Fw:=20 tube-6156

On Sat, 6 Oct 2001 18:53:46 -0400=20 "Carl & Kim Styan" <ve3by@bmts.com>
writes:
><= BR>>Correction=20 on one of the tube numbers. 3X300A1 should read=20 3X3000A1.
>73
>Carl

Hi Carl,
The 6156 = is an old=20 Amperex number for a premium 4-250A. May have also
been=20 manufactured by Eimac later -- I'll bet whoever made it marked=20 it!

The A1 is only useful as an audio amp.   = The A3=20 may be used as either
an audio amp or a grid driven RF amp. = Neither=20 is suitable for cathode
driven service with their low = µ. Do=20 you have any friend's who want to
build a big Tesla=20 coil?

73,
Marv =20 WC6W

>
>
>Came across 3 - 6156 = tubes=20 during my basement clean up. they look
>like =3D
>a = 4-400. Does=20 anyone has a cross reference for this = number.
>=3D20
>also=20 found:
>3X300A1 and a unused Econoco 3CX2500A3.
>If I = remember=20 the mu (20?) is much different from a 3CX3000A7. both =
>use=20 =3D
>the same coaxal socket as a 3CX3000A7.
>Are these = good for=20 SSB service. or land=20 = fill.
>=3D20
>73
>Carl
>=3D20
>

____= ____________________________________________________________
GET=20 INTERNET ACCESS FROM JUNO!
Juno offers FREE or PREMIUM Internet = access=20 for less!
Join Juno today! For your FREE software, = visit:
http://dl.www.juno.com/get/web/<= /A>.
------=_NextPart_000_0031_01C14EC1.F0C23A80-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From n4zr@contesting.com Sun Oct 7 06:26:51 2001 From: n4zr@contesting.com (Pete Smith) Date: Sun, 07 Oct 2001 01:26:51 -0400 Subject: [AMPS] SB-220 cooling/filaments Message-ID: <3.0.5.32.20011007012651.00950180@pop.abs.adelphia.net> Recently, thinking to help keep my SB-220 cool under contest conditions, I added a small 110v muffin fan pulling air from the top front of the tube compartment -- my thought was to enhance the overall flow of cooling air. The added fan is just sitting on top of the cabinet near the front edge, and subjective the cabinet does seem to be staying a bit cooler. Tonight, when I turned on the amplifier, I see only one filament lighting. My immediate thought is that I have melted the solder in the filament pins on that side from excessive heat. Is it plausible that the "helper" fan could have upset the normal flow sufficiently to have caused this? Or is it likely just a coincidence? I will be opening the amp up in the morning, checking for loose socket pins and DC continuity in the filament -- anything else to look for in particular? Thanks... 73, Pete N4ZR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From oz1pif@get2net.dk Sun Oct 7 08:19:34 2001 From: oz1pif@get2net.dk (Peter Frenning, OZ1PIF) Date: Sun, 7 Oct 2001 09:19:34 +0200 Subject: [AMPS] tube-6156 References: <014f01c14eb8$915c9f80$249eb7d8@ve3by> Message-ID: <001101c14f00$6a80ba20$0100a8be@oz1pif> This is a multi-part message in MIME format. ------=_NextPart_000_000E_01C14F11.2DF12020 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hi All, The 6156 is known in Europe as the QB3,5/750, it's a glass tetrode = capable of about 7-800W in class AB2 See more on my homepage under = http://hjem.get2net.dk/oz1pif/FL2000-QB.htm Vy 73 de OZ1PIF, Peter New DXpedition to Greenland for CQWW! See: http://www.qsl.net/xp1ab ********** OZ1PIF ************** email: oz1pif(no-spam-filler)@get2net.dk http://hjem.get2net.dk/oz1pif Shack Ph. +45 4619 3208 Snailmail: Peter Frenning Ternevej 23 DK-4130 Viby Sj. Denmark *********************************** ----- Original Message -----=20 From: Carl & Kim Styan=20 To: amps@contesting.com=20 Sent: Sunday, October 07, 2001 12:44 AM Subject: [AMPS] tube-6156 Came across 3 - 6156 tubes during my basement clean up. they look = like a 4-400. Does anyone has a cross reference for this number. =20 also found: 3X300A1 and a unused Econoco 3CX2500A3. If I remember the mu (20?) is much different from a 3CX3000A7. both = use the same coaxal socket as a 3CX3000A7. Are these good for SSB service. or land fill. =20 73 Carl =20 ------=_NextPart_000_000E_01C14F11.2DF12020 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hi All,

The 6156 is known in Europe as the = QB3,5/750, it's=20 a glass tetrode capable of about 7-800W in class AB2

See more on my homepage under http://hjem.get2ne= t.dk/oz1pif/FL2000-QB.htm

Vy 73 de OZ1PIF, Peter

New DXpedition to Greenland for CQWW! See: http://www.qsl.net/xp1ab

********** OZ1PIF **************
email:=20 oz1pif(no-spam-filler)@get2net.dk
http://hjem.get2net.dk/oz1pif<= BR>Shack=20 Ph. +45 4619 3208
Snailmail:
Peter Frenning
Ternevej = 23
DK-4130 Viby=20 Sj.
Denmark
***********************************

----- Original Message -----
From:=20 Carl & = Kim Styan=20
To: amps@contesting.com

Sent: Sunday, October 07, 2001 = 12:44=20 AM

Subject: [AMPS] tube-6156

Came across 3 - 6156 tubes during my = basement=20 clean up. they look like a 4-400. Does anyone has a cross reference = for this=20 number.

also found:

3X300A1 and a unused Econoco = 3CX2500A3.

If I remember the mu (20?) is much = different=20 from a 3CX3000A7. both use the same coaxal socket as a = 3CX3000A7.

Are these good for SSB service. or land=20 fill.

73

Carl

------=_NextPart_000_000E_01C14F11.2DF12020-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From g8gsq@qsl.net Sun Oct 7 09:36:57 2001 From: g8gsq@qsl.net (Steve Thompson) Date: Sun, 7 Oct 2001 09:36:57 +0100 Subject: [AMPS] Finding the Q of a Coil Message-ID: <001a01c14f0b$3a8df160$8a0d7ad5@jackie> -----Original Message----- From: Bill Smith To: amps@contesting.com Date: 07 October 2001 04:46 Subject: [AMPS] Finding the Q of a Coil > >Hung up trying to calculate the Q of a coil I want to >build. It will be 2 inches in diameter with 26 turns >of #10 wire. The length is 5.3 inches. 4.9 Turns per >inch. HAMCALC computes this at 11uh of inductance. > > >If I got it right >Inductive Reactance of this coil on 10 meters= >2*3.14*29000000*.000011 or 2003 ohms > >Q of this coil should be the Inductive Reactance >divided by the internal resistance of the coil's wire >(factoring in the RF). This is where I got bogged >down. Couldn't come up with an appropiate number. >Where am I going wrong? I'd say you're not going wrong. Calculating a resistance number to predict the Q can be done, but the few times I've tried it, the result hasn't matched all that well with the measured Q. Work out the skin depth, and given the circumference of the wire, you get the X section area of rf current flow. You know how long the coil is, so you can work out the rf resistance. Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sun Oct 7 09:51:14 2001 From: 2@vc.net (2) Date: Sun, 7 Oct 2001 01:51:14 -0700 Subject: [AMPS] SB-220 cooling/filaments Message-ID: <200110070851.f978pAZ09581@contesting.com> > >Recently, thinking to help keep my SB-220 cool under contest conditions, I >added a small 110v muffin fan pulling air from the top front of the tube >compartment -- my thought was to enhance the overall flow of cooling air. >The added fan is just sitting on top of the cabinet near the front edge, >and subjective the cabinet does seem to be staying a bit cooler. > // This arrangement should work since warm air exhausts on the left side of the cabinet and through the top of the cabinet. For optimal cooling, the SB-220 should have breathing room on the left, the top, and the rear of the cabinet - plus the fan motor bearings need to be oiled periodically. However, a cooling fan in good working order will keep things cool enough - unless max-berserko speech processing is used. >Tonight, when I turned on the amplifier, I see only one filament lighting. >My immediate thought is that I have melted the solder in the filament pins >on that side from excessive heat. Is it plausible that the "helper" fan >could have upset the normal flow sufficiently to have caused this? Or is >it likely just a coincidence? // One filament not lit is often caused either by solder melting out of pin 1 or 5, or it is caused by not enough spring tension on the corresponding socket pins - due to heat-caused loss of temper in the spring. Either condition is typically caused by not oiling the fan and/or interfering with the natural flow of cooling air. > good luck, Pete - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sun Oct 7 09:51:13 2001 From: 2@vc.net (2) Date: Sun, 7 Oct 2001 01:51:13 -0700 Subject: [AMPS] Finding the Q of a Coil Message-ID: <200110070851.f978p8Z09574@contesting.com> > >Hung up trying to calculate the Q of a coil I want to >build. It will be 2 inches in diameter with 26 turns >of #10 wire. The length is 5.3 inches. 4.9 Turns per >inch. HAMCALC computes this at 11uh of inductance. > > >If I got it right >Inductive Reactance of this coil on 10 meters= >2*3.14*29000000*.000011 or 2003 ohms > >Q of this coil should be the Inductive Reactance >divided by the internal resistance of the coil's wire >(factoring in the RF). This is where I got bogged >down. Couldn't come up with an appropiate number. >Where am I going wrong? // One needs to calculate, or preferably measure, the RF-R of the wire at 29MHz. However, with #10 Cu, it should handle c. 7Arms with ok efficiency at 29MHz. With XL=2k-ohms, this is much RF-V. cheers, Bill - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Ian White, G3SEK" References: <20011007034305.42803.qmail@web20501.mail.yahoo.com> Message-ID: Bill Smith wrote: > >Hung up trying to calculate the Q of a coil I want to >build. It will be 2 inches in diameter with 26 turns >of #10 wire. The length is 5.3 inches. 4.9 Turns per >inch. HAMCALC computes this at 11uh of inductance. > > >If I got it right >Inductive Reactance of this coil on 10 meters= >2*3.14*29000000*.000011 or 2003 ohms > >Q of this coil should be the Inductive Reactance >divided by the internal resistance of the coil's wire >(factoring in the RF). This is where I got bogged >down. Couldn't come up with an appropiate number. VE3ERP (Mr HAMCALC) has produced a new version that does just what you need. The theory is described the current QEX (Sept/Oct). The download address is www.arrl.org/qexfiles/ and the file is Murphy0901.zip Need to pick that up myself, too... 73 from Ian G3SEK Editor, 'The VHF/UHF DX Book' 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.com/g3sek -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From n4zr@contesting.com Sun Oct 7 12:40:15 2001 From: n4zr@contesting.com (Pete Smith) Date: Sun, 07 Oct 2001 07:40:15 -0400 Subject: [AMPS] Deoxit/ProGold Message-ID: <3.0.5.32.20011007074015.00960d90@pop.abs.adelphia.net> Elsewhere, people have highly recommended this stuff to improve the conductivity of connector and battery holder contacts which have become oxidized. I'm wondering if anyone has ever used it on filament contacts in an amplifier to reduce heat generation or restore ones that have become intermittent. Seem useful? 73, Pete N4ZR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From phil@vaxxine.com Sun Oct 7 13:50:48 2001 From: phil@vaxxine.com (Phil (VA3UX)) Date: Sun, 07 Oct 2001 08:50:48 -0400 Subject: [AMPS] Finding the Q of a Coil In-Reply-To: <20011007034305.42803.qmail@web20501.mail.yahoo.com> Message-ID: <5.0.2.1.0.20011007084237.009fda60@vaxxine.com> At 08:43 PM 10/6/2001 -0700, Bill Smith wrote: >Q of this coil should be the Inductive Reactance >divided by the internal resistance of the coil's wire >(factoring in the RF). This is where I got bogged >down. Couldn't come up with an appropiate number. >Where am I going wrong? Accurate calculation of RF resistance definitely is the tough part. There is more than one set of formulas from different sources for calculating this and the results don't agree. If I were forced to choose, I'd probably stick with the formulae in Terman's books. Steve T. correctly outlined the general procedure. I too will have a look at the Murphy file that Ian suggested. Phil >73, >Bill > >===== >Bill Smith KO4NR > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Sun Oct 7 15:07:51 2001 From: philk5pc@tyler.net (Phil Clements) Date: Sun, 7 Oct 2001 09:07:51 -0500 Subject: [AMPS] Tuned Input Circuit Q References: <200110060654.f966shZ11449@contesting.com> Message-ID: <005a01c14f39$75870e40$85084c42@phil> > // The statement that "or a parallel tuned network" should be > questioned. A parallel tuned input will work ok only when the Q > requirement is met and the average cathode-Z is close to 50-ohms. Or the old Alpha trick of using an un-un transformer with parallel tuned networks (when adding a second 8877 in the 77DX) can be employed. This is much easier than trying to tweak a pi network for each band when converting a 50 ohm tuned input to >50 ohms out. Only one part needs to be installed. (the un-un) This will also work with an existing pi network tuned input assembly. Just wind an un-un for the desired step-up/down ratio and solder it in. (((73))) Phil, K5PC (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w9op@athenet.net Sun Oct 7 15:22:09 2001 From: w9op@athenet.net (Mark Michel) Date: Sun, 7 Oct 2001 15:22:09 +0100 Subject: [AMPS] LK-8877 Message-ID: <007701c14f3b$7385d520$0100000a@w9op> Does anyone have info and/or manual for the LK-8877. Any help would be appreciated. Mark, W9OP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ToddRoberts2001@aol.com Sun Oct 7 17:52:48 2001 From: ToddRoberts2001@aol.com (ToddRoberts2001@aol.com) Date: Sun, 7 Oct 2001 12:52:48 EDT Subject: [AMPS] CIRCUIT BREAKER FOR TRANSFORMER PRIMARY CIRCUIT Message-ID: <80.112d6a42.28f1e260@aol.com> Can anyone recommend a suitable panel-mount 2-pole circuit breaker for the 240V primary circuit of a high-voltage transformer power supply? There are so many different types of circuit breakers available : Magnetic -Hydraulic, Thermal - Magnetic, medium-delay etc. the choice can be confusing. I would assume an instantaneous acting Magnetic-Hydraulic would be the best but even those seem to have different time-delay settings in catalogs I have looked at. Grainger seems to have a good selection but the catalog listings are confusing. I would guess a 20-25 amp rating would be good for a last line of defense and compatible with the ratings of my house wiring. Thanks for any suggestions. 73 Todd Roberts WD4NGG . -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From i4jmy@iol.it Sun Oct 7 18:45:08 2001 From: i4jmy@iol.it (Maurizio Panicara) Date: Sun, 7 Oct 2001 19:45:08 +0200 Subject: [AMPS] Finding the Q of a Coil References: <20011007034305.42803.qmail@web20501.mail.yahoo.com> Message-ID: <003801c14f57$dc7cccc0$f9900f97@i4jmy> You are nearly right, Q is the reactance divided by the equivalent resistance, that's the sum of ohmic losses plus the RF losses. Generally speaking anyway, what counts is often the circuit Q rather than the single component Q. For example, after all this is the AMP reflector, one can build a coil with Q=300 but the PI network where that coil will work could have been designed for a loaded value Q=10 (or even 2) , thus accepting lower quality inductors without any practical problem. Incidentally, sometimes the current and dissipation capabilities, rather than the Q, are much stringent parameters with inductors. 73, Mauri I4JMY ----- Original Message ----- From: "Bill Smith" To: Sent: Sunday, October 07, 2001 5:43 AM Subject: [AMPS] Finding the Q of a Coil > > Hung up trying to calculate the Q of a coil I want to > build. It will be 2 inches in diameter with 26 turns > of #10 wire. The length is 5.3 inches. 4.9 Turns per > inch. HAMCALC computes this at 11uh of inductance. > > > If I got it right > Inductive Reactance of this coil on 10 meters= > 2*3.14*29000000*.000011 or 2003 ohms > > Q of this coil should be the Inductive Reactance > divided by the internal resistance of the coil's wire > (factoring in the RF). This is where I got bogged > down. Couldn't come up with an appropiate number. > Where am I going wrong? > 73, > Bill > > ===== > Bill Smith KO4NR > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sun Oct 7 19:10:09 2001 From: 2@vc.net (2) Date: Sun, 7 Oct 2001 11:10:09 -0700 Subject: [AMPS] Deoxit/ProGold Message-ID: <200110071810.f97IA4Z19395@contesting.com> > >Elsewhere, people have highly recommended this stuff to improve the >conductivity of connector and battery holder contacts which have become >oxidized. I'm wondering if anyone has ever used it on filament contacts in >an amplifier to reduce heat generation or restore ones that have become >intermittent. Seem useful? > When socket contact springs have lost their springiness, contact pressure needs to be restored. The springiest 3-500Z contact springs are to be found in the TL-922's sockets. cheers, Pete - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sun Oct 7 19:10:11 2001 From: 2@vc.net (2) Date: Sun, 7 Oct 2001 11:10:11 -0700 Subject: [AMPS] Finding the Q of a Coil Message-ID: <200110071810.f97IA5Z19400@contesting.com> > >At 08:43 PM 10/6/2001 -0700, Bill Smith wrote: > >>Q of this coil should be the Inductive Reactance >>divided by the internal resistance of the coil's wire >>(factoring in the RF). This is where I got bogged >>down. Couldn't come up with an appropiate number. >>Where am I going wrong? > >Accurate calculation of RF resistance definitely is the tough part. There >is more than one set of formulas from different sources for calculating >this and the results don't agree. If I were forced to choose, I'd probably >stick with the formulae in Terman's books. > ... Amen, Phil. Better yet borrow a Q-meter. Simpler still, run full suds, shut down, and apply the thumb test. cheers - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sun Oct 7 19:10:13 2001 From: 2@vc.net (2) Date: Sun, 7 Oct 2001 11:10:13 -0700 Subject: [AMPS] Tuned Input Circuit Q Message-ID: <200110071810.f97IA7Z19406@contesting.com> > >> // The statement that "or a parallel tuned network" should be >> questioned. A parallel tuned input will work ok only when the Q >> requirement is met and the average cathode-Z is close to 50-ohms. > >Or the old Alpha trick of using an un-un transformer with parallel tuned >networks (when adding a second 8877 in the 77DX) can be employed. >This is much easier than trying to tweak a pi network for each band when >converting a 50 ohm tuned input to >50 ohms out. Only one part needs >to be installed. (the un-un) This will also work with an existing pi network >tuned input assembly. Just wind an un-un for the desired step-up/down >ratio and solder it in. > For me, changing the tuned inputs from 52-ohms out to 26-ohms out is preferable, Decrease L1, increase Cout, make Xc-in=20 - 25 ohms (Q=2.5 - 2.0). Tweak for best match. However, a second 8877 is only going to make c. a 2db difference at the Rx end, so it's a questionable expendature -- especially in view of extant tank problems when the second 8877 is added. cheers, Phil. - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sun Oct 7 19:22:31 2001 From: 2@vc.net (2) Date: Sun, 7 Oct 2001 11:22:31 -0700 Subject: [AMPS] Finding the Q of a Coil Message-ID: <200110071822.f97IMPZ19844@contesting.com> > >You are nearly right, Q is the reactance divided by the equivalent >resistance, that's the sum of ohmic losses plus the RF losses. >Generally speaking anyway, what counts is often the circuit Q rather than >the single component Q. >For example, after all this is the AMP reflector, one can build a coil with >Q=300 but the PI network where that coil will work could have been designed >for a loaded value Q=10 (or even 2) , thus accepting lower quality inductors >without any practical problem. >Incidentally, sometimes the current and dissipation capabilities, rather >than the Q, are much stringent parameters with inductors. > // Good points, Mauri. > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sun Oct 7 19:22:32 2001 From: 2@vc.net (2) Date: Sun, 7 Oct 2001 11:22:32 -0700 Subject: [AMPS] CIRCUIT BREAKER FOR TRANSFORMER PRIMARY CIRCUIT Message-ID: <200110071822.f97IMQZ19848@contesting.com> > >Can anyone recommend a suitable panel-mount 2-pole circuit breaker for the >240V primary circuit of a high-voltage transformer power supply? There are >so >many different types of circuit breakers available : Magnetic -Hydraulic, >Thermal - Magnetic, medium-delay etc. the choice can be confusing. I would >assume an instantaneous acting Magnetic-Hydraulic would be the best but even >those seem to have different time-delay settings in catalogs I have looked >at. Grainger seems to have a good selection but the catalog listings are >confusing. I would guess a 20-25 amp rating would be good for a last line of >defense and compatible with the ratings of my house wiring. Thanks for any >suggestions. 73 Todd Roberts WD4NGG . > // With the 18 - 20 db amplifiers that I built, I trusted the electric-mains' junction-box breakers to open if there was a problem. It works. cheers - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Sun Oct 7 21:35:29 2001 From: philk5pc@tyler.net (Phil Clements) Date: Sun, 7 Oct 2001 15:35:29 -0500 Subject: [AMPS] CIRCUIT BREAKER FOR TRANSFORMER PRIMARY CIRCUIT References: <200110071822.f97IMQZ19848@contesting.com> Message-ID: <001201c14f6f$9b59c3c0$a5074c42@phil> > // With the 18 - 20 db amplifiers that I built, I trusted the > electric-mains' junction-box breakers to open if there was a problem. It > works. I do about the same thing here. Each of my amps have their own dedicated 240 volt outlet, with breakers in the electric mains junction box sized to the load of each. As back-up, I use the large Buss NON type fuses in each power supply. I found that most of the cute 20-30 amp breakers for panel mounting on equipment racks are much slower than the common breakers used in service entrance panels. If your glitch resistors and breakers are sized correctly, the breakers will pop, and the resistors will not after a fault. Otherwise, most any breaker can be made to work. The value of the glitch resistor is selected to limit energy discharge from the filter caps to 50 joules, and the wattage of the glitch resistor is selected to keep it from self-destructing while the breaker is in transit. Sort of like designing a step-start system in reverse. (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Sun Oct 7 21:52:13 2001 From: philk5pc@tyler.net (Phil Clements) Date: Sun, 7 Oct 2001 15:52:13 -0500 Subject: [AMPS] Tuned Input Circuit Q References: <200110071810.f97IA7Z19406@contesting.com> Message-ID: <001a01c14f71$f17a2fe0$a5074c42@phil> > For me, changing the tuned inputs from 52-ohms out to 26-ohms out is > preferable, Decrease L1, increase Cout, make Xc-in=20 - 25 ohms (Q=2.5 - > 2.0). Tweak for best match. However, a second 8877 is only going to > make c. a 2db difference at the Rx end, so it's a questionable > expendature -- especially in view of extant tank problems when the second > 8877 is added. My comments were related directly to Alpha amps, Rich. Alpha did not use pi network input circuits in the 77 series amps. To prevent drilling many holes and adding expense, the "two-tube" kits furnished an un-un instead. No tweaking was required if the input L/C was correctly tuned to begin with. I will not get into the pros and cons of how loud or not loud the 2nd 8877 makes you. This "kit" was a way around the FCC regs that were in place at the time. Money is the motivation for converting a 77DX to an SX. A profit of $1500-$2000 was not uncommon for those in the "kit" installation business in the 80's. (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Bill Coleman" <001201c14f6f$9b59c3c0$a5074c42@phil> Message-ID: <009d01c14f73$dc4139a0$0100a8c0@ibm.com> A word of warning.... I recently replaced the Federal Pacific circuit breaker panel in my home because it was full of circuit breakers that might fail! Some time ago I had an occurance of a short in my HB amp where the amp breaker tripped but the panel breaker did not - I didn't pay much attention to it then. Recently I had reason to go into the panel - completely unrelated to any ham activity. Upon removing the cover, one breaker appeared to be 'loose' and there was considerable heating apparent on the bus where the 'loose' breaker was supposed to attach - this breaker was for a lighting circuit. To make a too long story short... There is lots of documentation online about Federal Pacific panel and breaker failures - especially two pole breakers failing to trip & panel fires when the breaker/bus connection fails. Federal Pacific is apparently no longer in the home market, but these breakers are still available. The sad thing is they are getting 'rare' and command 3X the price of other brands. The fix for me was a new Square D panel. 73, Bill ----- Original Message ----- From: "Phil Clements" To: "2" <2@vc.net>; ; "AMPS" Sent: Sunday, October 07, 2001 4:35 PM Subject: Re: [AMPS] CIRCUIT BREAKER FOR TRANSFORMER PRIMARY CIRCUIT > > > // With the 18 - 20 db amplifiers that I built, I trusted the > > electric-mains' junction-box breakers to open if there was a problem. It > > works. > > I do about the same thing here. Each of my amps have their own > dedicated 240 volt outlet, with breakers in the electric mains junction > box sized to the load of each. As back-up, I use the large Buss NON > type fuses in each power supply. I found that most of the cute 20-30 > amp breakers for panel mounting on equipment racks are much slower > than the common breakers used in service entrance panels. > If your glitch resistors and breakers are sized correctly, the breakers > will pop, and the resistors will not after a fault. Otherwise, most any > breaker can be made to work. The value of the glitch resistor is > selected to limit energy discharge from the filter caps to 50 joules, > and the wattage of the glitch resistor is selected to keep it from > self-destructing while the breaker is in transit. Sort of like designing > a step-start system in reverse. > > (((73))) > Phil, K5PC > > > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Ian White, G3SEK" References: <20011007034305.42803.qmail@web20501.mail.yahoo.com> <5.0.2.1.0.20011007084237.009fda60@vaxxine.com> Message-ID: Phil (VA3UX) wrote: > >At 08:43 PM 10/6/2001 -0700, Bill Smith wrote: > >>Q of this coil should be the Inductive Reactance >>divided by the internal resistance of the coil's wire >>(factoring in the RF). This is where I got bogged >>down. Couldn't come up with an appropiate number. >>Where am I going wrong? > >Accurate calculation of RF resistance definitely is the tough part. >There is more than one set of formulas from different sources for >calculating this and the results don't agree. If I were forced to >choose, I'd probably stick with the formulae in Terman's books. Steve >T. correctly outlined the general procedure. I too will have a look at >the Murphy file that Ian suggested. > I should have mentioned, it's all based on info from Terman. 73 from Ian G3SEK Editor, 'The VHF/UHF DX Book' 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.com/g3sek -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Sun Oct 7 23:10:52 2001 From: philk5pc@tyler.net (Phil Clements) Date: Sun, 7 Oct 2001 17:10:52 -0500 Subject: [AMPS] CIRCUIT BREAKER FOR TRANSFORMER PRIMARY CIRCUIT References: <200110071822.f97IMQZ19848@contesting.com> <001201c14f6f$9b59c3c0$a5074c42@phil> <009d01c14f73$dc4139a0$0100a8c0@ibm.com> Message-ID: <003b01c14f7c$ef0e10e0$a5074c42@phil> > To make a too long story short... There is lots of documentation online > about Federal Pacific panel and breaker failures - especially two pole > breakers failing to trip & panel fires when the breaker/bus connection > fails. Great point, Bill! That is why I always have the fuses in each power supply as a back-up. I learned a lot about CB's in my 33 year career as an airline pilot. Using them as "on-off" switches will weaken the mechanical parts inside the breaker. Then all bets are off as to what amperage it takes to trip them. Also repeated cycles of a breaker can deteriorate the internal contacts to a point where they carbonize, or even worse, weld themselves together. Putting a set of breakers on a radio panel lulls one into using it to switch the power on and off. I think research will find that the number of switch cycle times-before-failure (TBF, as the engineers call it,) are vastly less than a common switch. (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From nospam4me@juno.com Mon Oct 8 00:13:12 2001 From: nospam4me@juno.com (skipp isaham) Date: Sun, 7 Oct 2001 16:13:12 -0700 Subject: Fw: [AMPS] Deoxit/ProGold Message-ID: <20011007.161313.-308273.0.nospam4me@juno.com> - : From: Pete Smith : Elsewhere, people have highly recommended this : stuff to improve the conductivity of connector and battery : holder contacts which have become oxidized. - A high capacity battery connector (automotive and station type) should use the "picking type" oil/grease you find sold at local auto parts stores. The more common brands here are NOCO, I buy the spray can which lasts forever... part number NCP-2 from memory. It's red and you will not escape from it's power to ruin good clothing... ie your favorite shirt. - : I'm wondering if anyone has ever used it on filament : contacts in an amplifier to reduce heat generation or : restore ones that have become intermittent. Seem : useful? : 73, Pete N4ZR - Craig Labs products are hands down the only type of contact restoration products I trust to volume controls, switch contacts and related electronic Items. IMO the only real chemical animal that work well for most basic contacts... - I doubt the Progold will handle the high temp of some tube socket pins/flanges for the long term. For the short term, it should make quite a difference. That difference is less resistance... and the corresponding less heat. It might help, but it should not hurt. I've been coating contacts with it for years. Maybe I'll check to see if they offer anything for higher temp applications. - cheers skipp ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w2ge@home.com Mon Oct 8 00:30:29 2001 From: w2ge@home.com (Phil Levin W2GE) Date: Sun, 7 Oct 2001 19:30:29 -0400 Subject: [AMPS] Deoxit/ProGold In-Reply-To: <20011007.161313.-308273.0.nospam4me@juno.com> Message-ID: Improves Conductivity Maintains Optimum Signal Quality Protects Base Metals from Oxidation Forms Protective Anti-Tarnishing Layer Reduces Arcing, RFI and Intermittent Connections Reduces Wear and Abrasion Extended Temperature Range, -34oC to 200oC Skipp, above info is from CAIG ProGold site. States temp is good to 200C. Made me wonder, does anyone know the possible temp range of a brush to commutator surface in a DC run motor? I'm thinking about using this ProGold on a motor commutator to reduce resistance...??? Phil W2GE P.S. In the audiophile world, ProGold has had some very positive press. (However allot of high-end audiophile thinking is Voodoo if you ask me.) -----Original Message----- From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On Behalf Of skipp isaham Sent: Sunday, October 07, 2001 7:13 PM To: amps@contesting.com Subject: Fw: [AMPS] Deoxit/ProGold - : From: Pete Smith : Elsewhere, people have highly recommended this : stuff to improve the conductivity of connector and battery : holder contacts which have become oxidized. - A high capacity battery connector (automotive and station type) should use the "picking type" oil/grease you find sold at local auto parts stores. The more common brands here are NOCO, I buy the spray can which lasts forever... part number NCP-2 from memory. It's red and you will not escape from it's power to ruin good clothing... ie your favorite shirt. - : I'm wondering if anyone has ever used it on filament : contacts in an amplifier to reduce heat generation or : restore ones that have become intermittent. Seem : useful? : 73, Pete N4ZR - Craig Labs products are hands down the only type of contact restoration products I trust to volume controls, switch contacts and related electronic Items. IMO the only real chemical animal that work well for most basic contacts... - I doubt the Progold will handle the high temp of some tube socket pins/flanges for the long term. For the short term, it should make quite a difference. That difference is less resistance... and the corresponding less heat. It might help, but it should not hurt. I've been coating contacts with it for years. Maybe I'll check to see if they offer anything for higher temp applications. - cheers skipp ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 8 02:47:01 2001 From: 2@vc.net (2) Date: Sun, 7 Oct 2001 18:47:01 -0700 Subject: [AMPS] Tuned Input Circuit Q Message-ID: <200110080146.f981ktZ29249@contesting.com> > >> For me, changing the tuned inputs from 52-ohms out to 26-ohms out is >> preferable, Decrease L1, increase Cout, make Xc-in=20 - 25 ohms (Q=2.5 - >> 2.0). Tweak for best match. However, a second 8877 is only going to >> make c. a 2db difference at the Rx end, so it's a questionable >> expendature -- especially in view of extant tank problems when the second >> 8877 is added. > >My comments were related directly to Alpha amps, Rich. >Alpha did not use pi network input circuits in the 77 series amps. >To prevent drilling many holes and adding expense, the "two-tube" >kits furnished an un-un instead. No tweaking was required if the input >L/C was correctly tuned to begin with. > // Eimac recommends a low-pass Pi tuned input. >I will not get into the pros and cons of how loud or not loud the >2nd 8877 makes you. // A wise choice, Phil. The guys on AMPS who spent kilobucks on c. +2db imagine it made them the king of the pileup world and they bristle like porcupines at any suggestion that 1/3 of an S-unit is insignificant with normal QSB. > This "kit" was a way around the FCC regs >that were in place at the time. Money is the motivation for converting >a 77DX to an SX. A profit of $1500-$2000 was not uncommon for those >in the "kit" installation business in the 80's. > // Whew. The original 1980 Plywood Box amplifier cost c. $1300 in parts. cheers, Phil - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From n4zr@contesting.com Mon Oct 8 02:53:38 2001 From: n4zr@contesting.com (Pete Smith) Date: Sun, 07 Oct 2001 21:53:38 -0400 Subject: [AMPS] Hot SB-220 Message-ID: <3.0.5.32.20011007215338.00931340@pop.abs.adelphia.net> Tuirned out that the solder had melted out of one of the filament pins. I have resoldered it and ordered the high-capacity fan from Harbach/W8CQ. Thanks to Ian, VE7HHS, for his excellent erite-up on what jhe discovered re overheating of SB-220s. I'm hoping he will publish it to the reflector for the benefit uf us all! 73, Pete N4ZR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jprocyk@telus.net Mon Oct 8 03:19:49 2001 From: jprocyk@telus.net (Ian Procyk) Date: Sun, 7 Oct 2001 19:19:49 -0700 Subject: [AMPS] Findings surrounding SB-220 Heating Message-ID: <000001c14f9f$b5261210$2c04b440@RadioRoom> This is a multi-part message in MIME format. ------=_NextPart_000_0001_01C14F65.08CD5490 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit I have been asked to submit the exchange I had with Pete to the reflector, so here it goes. Hello, Pete I'm by no means an expert on the sb-220 amplifier, I'm 16years old and happen to have one I use on a regular basis contesting and the like. I have just kept an ear focused on this reflector service for ideas. However, I wouldn't mind communicating some common problems I have had with the sb-220 in relation to cooling. Like I say, I have used the sb-220 in many contesting situations where the amplifier was running hard for most of the 48 hours, with no problems, I have never yet had a filament go out during operation, yet I have had a filament go upon startup, (perhaps an indication that pin temperature rises too high if the amp is turned off after long stints of SSB operation?) When I bought the amp I was reluctant to remain using the limited stock fan of the sb-220, but being a cheap student I continued until approximately 6 months ago when I had the failure of the right (viewed from front) tube's filament. Needless to say I was very worried that I had lost the tube, but was EXSTATIC to find that the solder on the pin had melted and dripped out, somehow just enough that the filament would not light. I replaced the stock fan with a 6inch tube-axial fan capable of 230CFM (the stock fan was also 6" in diameter). I was very impressed with the cooling capability of the fan at 230cfm, I could key down with 1.3KW output at 2900V full load and it would take a little over 5minutes for the tubes to show any signs of being hot, mind you the power supply was humming. As an aside: I have followed through on Rick Measures (AG6K)'s idea of overhauling the bleeder resistors on the capacitor bank, with the new resistors of different value (I forget what they are), the total heat being dissipated by the bleeders has gone down very noticeably. However, I still have a small computer CPU fan mounted on standoff's over the cap-bank that cools that entire area with a little bit of air flow. This fan may not be needed now as that entire area is dissipating way less heat. When I bought the tube-axial fan I knew it was going to be loud and 10x overkill, but the idea in the end was to build a circuit that could control the rpm of the fan, thus making it tolerable. However, before I developed that circuit I had to try the fan out. It proved to be so loud that during one contest I gave up and placed the amplifier inside an empty cabinet of an old broadcast transmitter and kept a close eye on the wattmeter. After I finished the contest at VE7SCC, I decided that I better start work on the variable fan rpm idea, for know I have employed a very low tech solution, I'm using a step down transformer with a few secondary taps for voltages ranging between 60VAC-90VAC and I can switch them via an external switch. When running this particular 110VAC tube-axial fan around 60VAC the noise level is bearable, and the fan still puts out the air! However, one morning after a long night on 80m, I turned the amplifier on to chase some gray line dx, and I was shocked to see I had lost THE SAME FILAMENT yet again. I took the day off school (at the time it was secondary to this) :)) and I opened the amp to find the same melted pin. I knew that I had to do something so in the mean time I decided to solder the pin right to the socket until I could decide what to do. I managed to entice a good friend of mine, to *donate* a Johnson 275 socket that would replace the existing socket. The next week I de-soldered the tube from it's socket and overhauled the entire affair. A KEY OBSERVATION WAS NOTED: At the time when I had both the old and the new sockets sitting on the table I came to the conclusion that the old socket had lost it's spring tension on the filament pins..!!??? I researched this on the 'net and found this was a normal occurrence, that over the years, the heating and cooling will eventually deform the socket to the point where there is no longer perfect circular contact between the Johnson 275 filament socket and the tube's filament pin, thus creating only a few contact points all the way around the pin, this problem in turn raised the resistance of the connection and therefore more heat was induced. I replaced the socket successfully and have been running the amplifier with the same fan and new socket combination for about 1 year now. In the last year I have not encountered any problems with that socket, although I finally had to replace the second one, after it endured the same situation. I have opened and seen several other homebrew amplifiers even commercial amps including Kenwood's TL-992A and noticed one feature that seems to make sense: This is the fact that Kenwood paints the RF deck close to the 3-500's BLACK. This makes nothing but sense as black will "suck away" heat from the envelope of the tube and direct it to the chassis better then shiny aluminum surfaces will (if I can recall, Rick Measures points out the same thing on his website, and he recommends taking the steps to paint that part of the RF-deck black. Taking his advice, I took it upon myself to paint the RF-deck black. But before I did this I took a look at the anode while transmitting key down 1KW+ at HV plate voltage. Looking through the green cover, I got on the right angle to notice that the side of the anode facing the aluminum chassis was indeed quite a bit redder in color then the sides facing the Tank and the blower, This was apparent on both tubes! So the next weekend I painted that area black, and setup my experiment again. I now, was not able to detect any "hot spots" on the anode, whether it was facing the chassis or not, it was all a velvet color! Needless to say I was pleased. BOTTOM LINE: ~~~~~~~~~~~~~ I think if you implement the ideas I have described, you will be on your way to success, the key thing is to catch problems before they arise and do some preventative maintenance. This is hard for me to do as I rely solely on the income from cutting neighbor's laws, but for a working person this would be simple and very cheap for an amp of this proportion. A good idea would be to peruse AG6K's site and get an idea for some improvements you can implement on your SB-220: http://www.vcnet.com/measures/ ~~~~~~~~~~~~~~~~~~~~~~ 73 and take it easy, Ian Procyk, VE7HHS -----Original Message----- From: owner-amps@contesting.com [mailto:owner-amps@contesting.com] On Behalf Of Pete Smith Sent: Saturday, October 06, 2001 10:27 PM To: amps@contesting.com Subject: [AMPS] SB-220 cooling/filaments Recently, thinking to help keep my SB-220 cool under contest conditions, I added a small 110v muffin fan pulling air from the top front of the tube compartment -- my thought was to enhance the overall flow of cooling air. The added fan is just sitting on top of the cabinet near the front edge, and subjective the cabinet does seem to be staying a bit cooler. Tonight, when I turned on the amplifier, I see only one filament lighting. My immediate thought is that I have melted the solder in the filament pins on that side from excessive heat. Is it plausible that the "helper" fan could have upset the normal flow sufficiently to have caused this? Or is it likely just a coincidence? I will be opening the amp up in the morning, checking for loose socket pins and DC continuity in the filament -- anything else to look for in particular? Thanks... 73, Pete N4ZR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com ------=_NextPart_000_0001_01C14F65.08CD5490 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable

I have been asked to submit the exchange I had with = Pete to the reflector, so here it goes…

Hello, Pete

I'm by no means an expert on the sb-220 amplifier, I'm 16years old and happen to have one I use on a regular basis contesting = and the like. I have just kept an = ear focused on this reflector service for ideas. However, I wouldn't mind = communicating some common problems I have had with the sb-220 in relation to = cooling.

Like I say, I have used the sb-220 in many contesting situations where the = amplifier was running hard for most of the 48 hours, with no problems, I have = never yet had a filament go out during operation, yet I have had a filament go = upon startup, (perhaps an indication that pin temperature rises too high if = the amp is turned off after long stints of SSB operation?)

When I bought the amp I was reluctant to remain using the limited stock fan = of the sb-220, but being a cheap student I continued until approximately 6 months ago when I had the = failure of the right (viewed from front) tube's filament. Needless to say I was = very worried that I had lost the tube, but was EXSTATIC to find that the = solder on the pin had melted and dripped out, somehow just enough that the = filament would not light.

I replaced the stock fan with a 6inch tube-axial fan capable of 230CFM = (the stock fan was also 6" in diameter). I was very impressed with the cooling capability of the fan at = 230cfm, I could key down with 1.3KW output at 2900V full load and it would take a = little over 5minutes for the tubes to show any signs of being hot, mind you the = power supply was humming. =

As an aside: I have followed through on Rick Measures (AG6K)'s idea of = overhauling the bleeder resistors on the capacitor bank, with the new resistors of different value (I forget what they are), the total heat being = dissipated by the bleeders has gone down very noticeably. However, I still have a small = computer CPU fan mounted on standoff's over the cap-bank that cools that entire = area with a little bit of air flow. This fan may not be needed now as that = entire area is dissipating way less heat.

When I bought the tube-axial fan I knew it was going to be loud and 10x overkill, but the idea in the end was to build = a circuit that could control the rpm of the fan, thus making it tolerable. However, before I developed = that circuit I had to try the fan out. It proved to be so loud that during one = contest I gave up and placed the amplifier inside an empty cabinet of an old = broadcast transmitter and kept a close eye on the = wattmeter.

After I finished the contest at VE7SCC, I decided that I better start work on = the variable fan rpm idea, for know I have employed a very low tech = solution, I'm using a step down transformer with a few secondary taps for voltages = ranging between 60VAC-90VAC and I can switch them via an external switch. When running this particular = 110VAC tube-axial fan around 60VAC the noise level is bearable, and the fan = still puts out the air! However, one = morning after a long night on 80m, I turned the amplifier on to chase some gray = line dx, and I was shocked to see I had lost THE SAME FILAMENT yet again. I took the day off school (at = the time it was secondary to this) :)) and I opened the amp = to find the same melted pin. I = knew that I had to do something so in the mean time I decided to solder the pin = right to the socket until I could decide what to do. I managed to entice a good = friend of mine, to *donate* a Johnson 275 socket that would replace the existing socket. The next week I = de-soldered the tube from it's socket and overhauled the = entire affair. =

A KEY OBSERVATION WAS NOTED: = At the time when I had both the old and the new sockets sitting on the table I = came to the conclusion that the old socket had lost it's spring tension on the = filament pins..!!??? I researched this on the 'net and found this was a normal occurrence, that over the years, the heating and cooling will eventually = deform the socket to the point where there is no longer perfect circular = contact between the Johnson 275 filament socket and the tube's filament pin, = thus creating only a few contact points all the way around the pin, this = problem in turn raised the resistance of the connection and therefore more heat was induced.

I replaced the socket successfully and have been running the amplifier = with the same fan and new socket combination for about 1 year now. In the last year I have not = encountered any problems with that socket, although I finally had to replace the = second one, after it endured the same situation.

I have opened and seen several other homebrew amplifiers even commercial = amps including Kenwood's TL-992A and noticed one feature that seems to make sense: This is the fact = that Kenwood paints the RF deck close to the 3-500's BLACK. This makes nothing but sense as = black will "suck away" heat from the envelope of the tube and direct = it to the chassis better then shiny aluminum surfaces will (if I can recall, = Rick Measures points out the same thing on his website, and he recommends = taking the steps to paint that part of the RF-deck black.

Taking his advice, I took it upon myself to paint the RF-deck black. But before I did this I took a = look at the anode while transmitting key down 1KW+ at HV plate voltage. Looking through the green = cover, I got on the right angle to notice that the side of the anode facing the = aluminum chassis was indeed quite a bit redder in color then the sides facing the = Tank and the blower, This was apparent on both tubes! So the next weekend I = painted that area black, and setup my experiment again. I now, was not able to detect = any "hot spots" on the anode, whether it was facing the chassis or = not, it was all a velvet color! Needless to say I was = pleased.

BOTTOM LINE:

~~~~~~~~~~~~~

I think if you implement the ideas I have described, you will be on your = way to success, the key thing is to catch problems before they arise and do = some preventative maintenance. = This is hard for me to do as I rely solely on the income from cutting neighbor's = laws, but for a working person this would be simple and very cheap for an amp = of this proportion.

A good idea would be to peruse AG6K's site and get an idea for some = improvements you can implement on your SB-220:

http://www.vcnet.com/measures/

~~~~~~~~~~~~~~~~~~~~~~

73 and take it easy,

Ian Procyk,

VE7HHS

-----Original Message-----

From: owner-amps@contesting.com [mailto:owner-amps@contesting.co= m] On Behalf Of Pete = Smith

Sent: Saturday, October 06, 2001 10:27 PM

To: amps@contesting.com

Subject: [AMPS] SB-220 cooling/filaments

Recently, thinking to help keep my SB-220 cool under contest conditions, I added a = small 110v muffin fan pulling air from the top front of the tube compartment = -- my thought was to enhance the overall flow of cooling air. The added fan is = just sitting on top of the cabinet near the front edge, and subjective the = cabinet does seem to be staying a bit cooler.

Tonight, when I turned on the amplifier, I see only one filament lighting. My = immediate thought is that I have melted the solder in the filament pins on that = side from excessive heat. Is it = plausible that the "helper" fan could have upset the normal flow = sufficiently to have caused this? Or is = it likely just a coincidence? =

I will be opening the amp up in the morning, checking for loose socket = pins and DC continuity in the filament -- anything else to look for in = particular?

Thanks...

73, Pete N4ZR

--

FAQ on WWW:       &nbs= p;       http://www.contesting.com/FAQ= /amps

Submissions:       &nbs= p;      amps@contesting.com

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Problems:       &nbs= p;         owner-amps@contesting.com

------=_NextPart_000_0001_01C14F65.08CD5490-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Mon Oct 8 03:35:36 2001 From: philk5pc@tyler.net (Phil Clements) Date: Sun, 7 Oct 2001 21:35:36 -0500 Subject: [AMPS] Tuned Input Circuit Q References: <200110080146.f981ktZ29249@contesting.com> Message-ID: <001501c14fa1$eaff1880$d4084c42@phil> > // Eimac recommends a low-pass Pi tuned input. Alpha thought otherwise for years. Denny Had thought otherwise for years. Eimac still honored their warranty, and the FCC did not seem to care. (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ko4nrbs@yahoo.com Mon Oct 8 06:42:58 2001 From: ko4nrbs@yahoo.com (Bill Smith) Date: Sun, 7 Oct 2001 22:42:58 -0700 (PDT) Subject: [AMPS] Ameritron AL-1200 Message-ID: <20011008054258.69308.qmail@web20509.mail.yahoo.com> How long has the Ameritron AL-1200 been out? I keep hearing so many good things about them I'm about ready to buy one for myself. 73, Bill ===== Bill Smith KO4NR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From yo9fzs@office.deck.ro Mon Oct 8 08:16:25 2001 From: yo9fzs@office.deck.ro (yo9fzs) Date: Mon, 08 Oct 2001 09:16:25 +0200 Subject: [AMPS] Fan->make correct and 8877 vs GS35 References: <007c01c14de5$2e9d6100$ba775dd3@8163> <000c01c14de7$a4ec0580$01785dd3@8163> Message-ID: <3BC152C8.42506F83@office.deck.ro> Hello Xu, These (axial) fans are not suitable for cooling the 4CX1000 tube, especially if you want to get high or full output. Anyway, I saw many russian amplifiers made by UA hams, they are using such fans for cooling GI7, GU43 (1kW out), GU74 (600W out), or even GU78 tubes. Some high speed/high air volume/high pressure axial fan are made but they use 400Hz AC line (like the one used for Harris RF110A), and are also very noisy. The radial (blowers) ones are the best, and some noise will be allways present... There are both mechanical and electrical differences between the GS 35 and the 3CX1500/8877. If you need I can send you data for both. 73, Traian Xu wrote: > Hi! > I have many square fans,some of them for 220AC,some of them for > DC12V,could someone tell me how to cauculate the LPM(litre per minute) > depend > on the current of 220V AC and DC12V?I have a pair 30W AC Fan,can use in a > Chinese FU-100F(4CX1000)?I have a Chinese Military 1.6KW HF SSB > transmitter(use a FU-100F),but origional fan is too noisy.ps what diffrent > between > GS35 and 8877? > > 73! de Xu > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From g8gsq@qsl.net Mon Oct 8 08:09:54 2001 From: g8gsq@qsl.net (Steve Thompson) Date: Mon, 8 Oct 2001 08:09:54 +0100 Subject: [AMPS] Discharge energy Message-ID: <003d01c14fc8$586126e0$b7907ad5@jackie> >From Phil, K5PC: >The value of the glitch resistor is >selected to limit energy discharge from the filter caps to 50 joules, >and the wattage of the glitch resistor is selected to keep it from >self-destructing while the breaker is in transit. First of all, please can I stress that my comments are NOT intended as specific to Phil - his posting contains a comment I've seen a number of times, which might appear in some manufacturer's info and which puzzles me a bit. Phil's posting gets used purely because I've chosen this moment to make my comment. The energy in the filter caps is defined as 1/2*C*V^2. I'm puzzled as to how a glitch resistor allows the *energy* in a discharge to be controlled. To my mind, it can only set the peak current and the time constant. Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Mon Oct 8 09:52:00 2001 From: W8JI@contesting.com (Tom Rauch) Date: Mon, 8 Oct 2001 04:52:00 -0400 Subject: [AMPS] Finding the Q of a Coil In-Reply-To: References: <5.0.2.1.0.20011007084237.009fda60@vaxxine.com> Message-ID: <3BC130F0.77.703A69A@localhost> > >Accurate calculation of RF resistance definitely is the tough part. > >There is more than one set of formulas from different sources for > >calculating this and the results don't agree. If I were forced to > >choose, I'd probably stick with the formulae in Terman's books. > >Steve T. correctly outlined the general procedure. I too will have a > >look at the Murphy file that Ian suggested. > > > I should have mentioned, it's all based on info from Terman. This is one of the cases I have found where you had just better measure the component. It seems is difficult if not virtually impossible to get close to actual component Q using formulas. Many things are at issue besides wire resistance. Every Q formula working off coil dimensions or program I have tried has never been close. The work by Czerwinski in August 26 1960 Electronics comes closest, while some of Terman's stuff is miles from being correct. The highest Q's I have ever measured are in the upper hundreds (~800) for large well designed transmitting-type inductors operated reasonably far below the self-resonant frequency of the inductor. You can test or judge any formulas by looking to see if inputs contain: 1.) Length to diameter 2.) Conductor spacing 3.) Conductor type and construction (unless assumed to be the type you are using) 4.) Frequency What you should see is an increase in Q and a peak someplace below the self-resonant frequency. If you see Q's of more than several hundred's with any RF inductor, watch out! The best text I have found on this is in Kuecken's "Antennas and Transmission Lines" in the chapter on "Reactance Elements and Impedance Limits", although it deals only with airwound inductors using bare solid round conductors. Stray capacitance in an RF inductor greatly affects Q, and so if you don't see a definite upward slope of Q with frequency, limiting at perhaps 1000 or less, and an abrupt drop above the peak with much lower Q as the self-resonant frequency is approached something is wrong. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Mon Oct 8 09:52:00 2001 From: W8JI@contesting.com (Tom Rauch) Date: Mon, 8 Oct 2001 04:52:00 -0400 Subject: [AMPS] Tuned Input Circuit Q In-Reply-To: <001501c14fa1$eaff1880$d4084c42@phil> Message-ID: <3BC130F0.8688.703A6DF@localhost> > Denny Had thought otherwise for years. > Eimac still honored their warranty, and the FCC > did not seem to care. None of that matters Phil, because none of that means anything. None of them are concerned about what improper Q or circuit style would do. The only potential problems are a lack of maximum efficiency and IMD performance in cases where the harmonics distort cathode waveform, or exciter shutdown in solid state rigs if cathode harmonics make it back to the SWR sensing system. The first time I ever saw a severe problem was in a homebrew pair of 3-500Z's, that only made 45% efficiency on 15 meters despite a perfect SWR on the input, and two-tone was -32 3rd below one tone. Doing a proper tuned input raised everything to normal ranges. The FCC, Eimac's warranty dept, and Denny Had would never care about something like that. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Mon Oct 8 11:06:39 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Mon, 8 Oct 2001 11:06:39 +0100 Subject: [AMPS] Noises in electrolytic capacitors Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A92C@excalibur.swindon.msl.mitel.com> I'm back - typing one handed, not plastered, possibly a fracture, possibly torn tendons. Most of the last two weeks has been spent in a drug induced haze, so I guess I could have made as much sense as usual here. Awaiting a date from hospital for an MRI scan - wonder if there's any useful bits spare in the machine! I've had the ticking electrolytics and the only answer was replacement. Wirewound resistors can be unreliable in the high values if they crack the coating, or can suffer corrosion. Years ago, I worked at a company called Labgear, who at one time made ham gear. They also made their own wirewound resistors, and had gone for cement coating. They found that the ham gear ones were unreliable, but the ones used in commercial 24/7 applications weren't, and the problem was that the cement coating allowed moisture in, and they got electrolysis. The commercial ones were constantly warm enough that the moisture didn't get in...... Not sure what Rich means by a 'six pack of 811's'. Is that real beer as opposed to the usual US stuff that's an 807? (most of which would be better designated a 955!) I don't know of anyone electrocuted by not having bleeders, although there was a case many years back of a big (multi MVA 275kV) xfmr having charge left in the windings after switch off which threw someone across the shop and killed them. Strangely, that was alleged to have the been the transformer involved in the Hixon rail crash in the 1960's. Still like 'safety' bleeders as well, but don't rely on them. Incidentally, I just splashed out on a professional 40kV DC probe so I can measure HV rather than guessing...........seems worth it from a safety viewpoint, somehow. A clip lead across the HV during work is a good idea - just don't forget to remove it afterwards! 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 8 12:22:09 2001 From: 2@vc.net (2) Date: Mon, 8 Oct 2001 04:22:09 -0700 Subject: [AMPS] Tuned Input Circuit Q Message-ID: <200110081122.f98BM2Z07593@contesting.com> > >> // Eimac recommends a low-pass Pi tuned input. > >Alpha thought otherwise for years. // Dick Errorhorn used Centralab coupling/bypassing service capacitors as C-tune and C-load tank padders. He also used carbon-comp resistors that were rated at 350V max as equalizer resistors on 450V electrolytics. >Denny Had thought otherwise for years. Denny Had sent Eimac the prototype for the MLA2500 for evaluation. Two Eimac engineers recommended numerous changes. Mr. Had made none of Eimac's recommended changes prior to going into production. >Eimac still honored their warranty, Eimac honors their warranty even in cases of gold sputtering. >and the FCC did not seem to care. FCC specs can be met without a tuned input. cheers, Phil - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Ian White, G3SEK" References: <003d01c14fc8$586126e0$b7907ad5@jackie> Message-ID: Steve Thompson wrote: > >From Phil, K5PC: >>The value of the glitch resistor is >>selected to limit energy discharge from the filter caps to 50 joules, >>and the wattage of the glitch resistor is selected to keep it from >>self-destructing while the breaker is in transit. > >First of all, please can I stress that my comments are NOT intended as >specific to Phil - his posting contains a comment I've seen a number of >times, which might appear in some manufacturer's info and which puzzles me a >bit. Phil's posting gets used purely because I've chosen this moment to make >my comment. > >The energy in the filter caps is defined as 1/2*C*V^2. I'm puzzled as to how >a glitch resistor allows the *energy* in a discharge to be controlled. To my >mind, it can only set the peak current and the time constant. > When the capacitor is discharged through the series combination of the resistor and the tube, the stored energy is divided between those two components. Strictly speaking the energy going into the tube is not limited, but shared. If there is an arc, the voltage across the tube drops to only a few tens of volts, so almost all the energy from a HV supply goes into the series resistor. In that sense the resistor limits the energy available to go into the tube. Eimac Bulletin #17 recommends an energy limit of about 4J for indirectly-heated tubes up to 1500W dissipation (as a rough way of classifying tubes according to size) and suggests that this can be achieved by limiting the peak current to 40A. Directly-heated tubes are less subject to arc damage, but Eimac point out that damage to the control grid of a smaller triode such as the 3-500Z may also be a limiting factor, since the grid is at the receiving end of an arc from the anode. All this is pretty hand-waving stuff because controlled experiments are very hard to do. The best we can hope for is guidelines, and they come with no guarantees. There are obviously other resistive elements in the loop, notably the internal resistance of a string of electrolytics, which explains why tubes do survive with smaller glitch resistors than Eimac would recommend, or indeed with none at all. The important thing, as Phil said, is that the resistor is big enough to hold together while the fuses or breakers are operating, because you can't guarantee that it will fail open-circuit. 73 from Ian G3SEK Editor, 'The VHF/UHF DX Book' 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.com/g3sek -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From g8gsq@qsl.net Mon Oct 8 13:25:14 2001 From: g8gsq@qsl.net (Steve Thompson) Date: Mon, 8 Oct 2001 13:25:14 +0100 Subject: [AMPS] Discharge energy Message-ID: <001801c14ff4$4945a4c0$993d7ad5@office> -----Original Message----- From: Ian White, G3SEK To: amps@contesting.com Date: 08 October 2001 13:00 Subject: Re: [AMPS] Discharge energy > >Steve Thompson wrote: >> >>From Phil, K5PC: >>>The value of the glitch resistor is >>>selected to limit energy discharge from the filter caps to 50 joules, >>>and the wattage of the glitch resistor is selected to keep it from >>>self-destructing while the breaker is in transit. >> >>First of all, please can I stress that my comments are NOT intended as >>specific to Phil - his posting contains a comment I've seen a number of >>times, which might appear in some manufacturer's info and which puzzles me a >>bit. Phil's posting gets used purely because I've chosen this moment to make >>my comment. >> >>The energy in the filter caps is defined as 1/2*C*V^2. I'm puzzled as to how >>a glitch resistor allows the *energy* in a discharge to be controlled. To my >>mind, it can only set the peak current and the time constant. >> > >When the capacitor is discharged through the series combination of the >resistor and the tube, the stored energy is divided between those two >components. Strictly speaking the energy going into the tube is not >limited, but shared. > >If there is an arc, the voltage across the tube drops to only a few tens >of volts, so almost all the energy from a HV supply goes into the series >resistor. In that sense the resistor limits the energy available to go >into the tube. The fog clears. Thanks, Ian Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jtml@lanl.gov Mon Oct 8 14:25:05 2001 From: jtml@lanl.gov (John Lyles) Date: Mon, 8 Oct 2001 07:25:05 -0600 Subject: [AMPS] circuit breaker recommendation Message-ID: For years I have used panel mounted breakers like the Airpax, ETA, Potter Brumfield W91X series, Seimens, etc. I think a number of manufacturers have consolidated a bit, but most make similar packages that can be uses as a second source for each other. The instantaneous MH is fine, it really isn't instantaneous but closer than a thermal breaker I would guess. Just rate it to be above the RMS current you plan on drawing (also the inrush if you don't have step start should be considered, and either the delay curve for the breaker chosen for this, or a slightly larger breaker chosen. Breakers are rated for line to ground voltage, for a 2 pole breaker. It is very difficult to find a 480 VAC panel mounted breaker, for instance. However one realizes that 277 volts is all that is present with respect to ground. High speed electronic crowbar or overcurrent sensing can be used to open the primary power and the breaker protects your wiring and iron from burning up in a direct short. Some breakers can be obtained with separate trip coils which can be triggered from an overcurrent circuit to remove AC power that way. Only thing is that you might drop cooling, filaments and all this way and perhaps you want to keep a little cooling going until your tube cools down (depends on if bottle or with handles, etc.). These breakers are sold at Allied and Newark among other distributors. Good choices... 73 John K5PRO >Date: Sun, 7 Oct 2001 12:52:48 EDT >From: ToddRoberts2001@aol.com >Subject: [AMPS] CIRCUIT BREAKER FOR TRANSFORMER PRIMARY CIRCUIT > >Can anyone recommend a suitable panel-mount 2-pole circuit breaker for the >240V primary circuit of a high-voltage transformer power supply? There are so >many different types of circuit breakers available : Magnetic -Hydraulic, >Thermal - Magnetic, medium-delay etc. the choice can be confusing. I would >assume an instantaneous acting Magnetic-Hydraulic would be the best but even >those seem to have different time-delay settings in catalogs I have looked >at. Grainger seems to have a good selection but the catalog listings are >confusing. I would guess a 20-25 amp rating would be good for a last line of >defense and compatible with the ratings of my house wiring. Thanks for any >suggestions. 73 Todd Roberts WD4NGG . -- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 8 14:38:36 2001 From: 2@vc.net (2) Date: Mon, 8 Oct 2001 06:38:36 -0700 Subject: [AMPS] Ameritron AL-1200 Message-ID: <200110081338.f98DcSZ10453@contesting.com> > >How long has the Ameritron AL-1200 been out? I keep >hearing so many good things about them I'm about ready >to buy one for myself. // Until Ameritron/MFJ switches from the 3CX1200A7 to the much-improved 3CX1200Z7, this is probably not a good time to purchase one. Eimac's Z7 has been out for several years, it costs little more than an A7, so Tom Rauch should be updating with the improved tube -- and hopefully adding: a glitch resistor in the +HV, forced air cooling on the tank / bandswitch, larger tank L conductors, step-start. and removing the "neutralization". However, an obstacle appears to be technological hubris. cheers, Bill - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 8 14:38:38 2001 From: 2@vc.net (2) Date: Mon, 8 Oct 2001 06:38:38 -0700 Subject: [AMPS] Noises in electrolytic capacitors Message-ID: <200110081338.f98DcVZ10458@contesting.com> > >I'm back - typing one handed, not plastered, possibly a fracture, possibly torn >tendons. Most of the last two weeks has been spent in a drug induced haze, so I >guess I could have made as much sense as usual here. Awaiting a date from >hospital for an MRI scan - wonder if there's any useful bits spare in the >machine! > >I've had the ticking electrolytics and the only answer was replacement. >Wirewound resistors can be unreliable in the high values if they crack the >coating, or can suffer corrosion. Wire-wound, high-ohm resistors are unreliable without corrosion and without cracking due to frangible nature of the fine wire used in making them, and due to frequent heat-cycling in ham radio service. MOF resistors are more reliable. > >Years ago, I worked at a company called Labgear, who at one time made ham gear. >They also made their own wirewound resistors, and had gone for cement >coating. >They found that the ham gear ones were unreliable, but the ones used in >commercial 24/7 applications weren't, and the problem was that the cement >coating allowed moisture in, and they got electrolysis. The commercial >ones were >constantly warm enough that the moisture didn't get in...... > Amen >Not sure what Rich means by a 'six pack of 811's'. Is that real beer as >opposed to the usual US stuff that's an 807? "811s" are larger glass bottles. Real beer comes from Deutchland and the Emerald Isle. > (most of which would be better designated a 955!) > Chortle >I don't know of anyone electrocuted by not having bleeders, although there >was a case many years back of a big (multi MVA 275kV) xfmr having charge left in >the windings after switch off which threw someone across the shop and killed them. >Strangely, that was alleged to have the been the transformer involved in the >Hixon rail crash in the 1960's. Still like 'safety' bleeders as well, but >don't rely on them. Incidentally, I just splashed out on a professional 40kV DC probe >so I can measure HV rather than guessing...........seems worth it from a >safety viewpoint, somehow. A clip lead across the HV during work is a good idea - >just don't forget to remove it afterwards! > Amen to that. A local repairman was recently killed when some schmuck switched on the mains breaker while he was doing repairs. A shorting device would have saved his life. > cheers, Peter - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 8 14:38:40 2001 From: 2@vc.net (2) Date: Mon, 8 Oct 2001 06:38:40 -0700 Subject: [AMPS] Discharge energy Message-ID: <200110081338.f98DcWZ10465@contesting.com> > >From Phil, K5PC: >>The value of the glitch resistor is >>selected to limit energy discharge from the filter caps to 50 joules, >>and the wattage of the glitch resistor is selected to keep it from >>self-destructing while the breaker is in transit. > >First of all, please can I stress that my comments are NOT intended as >specific to Phil - his posting contains a comment I've seen a number of >times, which might appear in some manufacturer's info and which puzzles me a >bit. Phil's posting gets used purely because I've chosen this moment to make >my comment. > >The energy in the filter caps is defined as 1/2*C*V^2. I'm puzzled as to how >a glitch resistor allows the *energy* in a discharge to be controlled. To my >mind, it can only set the peak current and the time constant. > Good point, Steve. Congrats. - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 8 14:38:42 2001 From: 2@vc.net (2) Date: Mon, 8 Oct 2001 06:38:42 -0700 Subject: [AMPS] Tuned Input Circuit Q Message-ID: <200110081338.f98DcYZ10471@contesting.com> > >> Denny Had thought otherwise for years. >> Eimac still honored their warranty, and the FCC >> did not seem to care. > >None of that matters Phil, because none of that means anything. > >None of them are concerned about what improper Q or circuit style >would do. > >The only potential problems are a lack of maximum efficiency and >IMD performance in cases where the harmonics distort cathode >waveform, or exciter shutdown in solid state rigs if cathode >harmonics make it back to the SWR sensing system. > >The first time I ever saw a severe problem was in a homebrew pair >of 3-500Z's, that only made 45% efficiency on 15 meters despite a >perfect SWR on the input, and two-tone was -32 3rd below one >tone. Doing a proper tuned input raised everything to normal ranges. > >The FCC, Eimac's warranty dept, and Denny Had would never care >about something like that. > // So why does the AL-1200 reportedly have low efficiency on 15m and 10m? - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 8 14:38:43 2001 From: 2@vc.net (2) Date: Mon, 8 Oct 2001 06:38:43 -0700 Subject: [AMPS] Finding the Q of a Coil Message-ID: <200110081338.f98DcbZ10478@contesting.com> > >> >Accurate calculation of RF resistance definitely is the tough part. >> >There is more than one set of formulas from different sources for >> >calculating this and the results don't agree. If I were forced to >> >choose, I'd probably stick with the formulae in Terman's books. >> >Steve T. correctly outlined the general procedure. I too will have a >> >look at the Murphy file that Ian suggested. >> > >> I should have mentioned, it's all based on info from Terman. > >This is one of the cases I have found where you had just better >measure the component. > // I have seen too many VHF antennas where the calculated gain was different than the measured gain. It is no wonder that *QST* does not allow antenna manufacturers to make gain claims. In CB rags, one finds gain claims of 11+db for 3-element yagis. >It seems is difficult if not virtually impossible to get close to actual >component Q using formulas. Many things are at issue besides >wire resistance. Every Q formula working off coil dimensions or >program I have tried has never been close. > >The work by Czerwinski in August 26 1960 Electronics comes >closest, while some of Terman's stuff is miles from being correct. // Terman's inductance formula predicts that the L of 1-inch/25mm width copper strap is about 10nH per inch. However, in the Rauchian world, an inch of such strap has zero inductance -- especially when it is used to ground a grid. > cheers - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Mon Oct 8 14:41:17 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Mon, 8 Oct 2001 14:41:17 +0100 Subject: [AMPS] Noises in electrolytic capacitors Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A93A@excalibur.swindon.msl.mitel.com> Rich said: >Real beer comes from Deutchland and the Emerald Isle. That's fighting talk! A lot of good beer comes from England: a small amount from Wales and Scotland. Belgium produces some very good stuff, and the only decent Budweiser is from Budvar in the Czech republic. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From n4zr@contesting.com Mon Oct 8 15:39:18 2001 From: n4zr@contesting.com (Pete Smith) Date: Mon, 08 Oct 2001 10:39:18 -0400 Subject: [AMPS] SB-220 cooling Message-ID: <3.0.5.32.20011008103918.008d4180@pop.abs.adelphia.net> Well, I resoldered the pin yet again and thoroughly polished the filament pins, and so far the repair seems to be holding. The socket seems to be reasonably tight on the filament pins, so I hope it's not socket replacement time yet. This raises a question, though -- I had assumed that the main source of the heat that melts the pins was heat dissipated inside the tube element. Now I'm wondering whether it may not be simple resistive heating from imperfect contact between the pins and the socket. Anyone have a view on which effect predominates? I also notice that my amp seems to breathe a LOT better with the case off (but the cage and deflector plate in place, of course. A foot away from the top of the cage I can feel a nice breeze. Perhaps I should just leave it this way (without the outer case) for contest use. comments? 73, Pete N4ZR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Mon Oct 8 18:06:08 2001 From: philk5pc@tyler.net (Phil Clements) Date: Mon, 8 Oct 2001 12:06:08 -0500 Subject: [AMPS] Tuned Input Circuit Q References: <3BC130F0.8688.703A6DF@localhost> Message-ID: <000d01c1501b$89091f20$a6084c42@phil> > > Denny Had thought otherwise for years. > > Eimac still honored their warranty, and the FCC > > did not seem to care. > > None of that matters Phil, because none of that means anything. > You are taking me out of context, Tom. I was replying to Rich's statement that Eimac recommends a pi input network. I was just pointing out that using a parallel network (or none at all) will not void their warranty. Using a parallel network or none at all will not necessarily cause excess IMD causing the FCC to not type accept a radio. ETO, Dentron, and others are proof that parallel input networks and even some sort of a "T" network may not be optimum, but may be acceptable. You, Rich, and Eimac like pi networks. Creative Electronics, RF Power Products, ETO-Alpha. myself, and others like parallel or T networks. We all have sufficiently clean, and type accepted products on the air daily. You are not going to change me and I am not going to change you. As with parasitic suppressors and other components in an amp, there are CHOICES which all arrive at acceptable results. (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Mon Oct 8 18:14:09 2001 From: philk5pc@tyler.net (Phil Clements) Date: Mon, 8 Oct 2001 12:14:09 -0500 Subject: [AMPS] Tuned Input Circuit Q References: <20011008112030.GCAT24924.io@vcnet.com> Message-ID: <003501c1501c$a5a8e420$a6084c42@phil> > FCC specs can be met without a tuned input. That is my point, exactly. They can also be met and exceeded with a parallel or T network. (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 8 19:14:08 2001 From: 2@vc.net (2) Date: Mon, 8 Oct 2001 11:14:08 -0700 Subject: [AMPS] An apology Message-ID: <200110081814.f98IDxZ19667@contesting.com> Today, YS1XS informed me that the AL-80A manual states that the max plate current is 550mA for the 3-500Z. Obviusly, I was wrong about the 500mA figure. My apologies to Mr. Rauch and his faithful groupies. cheers - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 8 19:14:09 2001 From: 2@vc.net (2) Date: Mon, 8 Oct 2001 11:14:09 -0700 Subject: [AMPS] Noises in electrolytic capacitors Message-ID: <200110081814.f98IE0Z19671@contesting.com> > >Rich said: > >>Real beer comes from Deutchland and the Emerald Isle. > >That's fighting talk! A lot of good beer comes from England: a small amount from >Wales and Scotland. Belgium produces some very good stuff, and the only >decent Budweiser is from Budvar in the Czech republic. > "In taste there is no dispute." > cheers, Peter - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From baycock@HIWAAY.NET Mon Oct 8 19:33:23 2001 From: baycock@HIWAAY.NET (Bill Aycock) Date: Mon, 08 Oct 2001 13:33:23 -0500 Subject: [AMPS] An apology In-Reply-To: <200110081814.f98IDxZ19667@contesting.com> Message-ID: <3.0.5.32.20011008133323.01a3a7a0@HIWAAY.NET> Rich- when you are wrong, and caught, you (once in a blue moon) admit it. When you try to be a horses A**, you do a better, more complete, job. Bill-W4BSG At 11:14 AM 10/8/01 -0700, you wrote: > >Today, YS1XS informed me that the AL-80A manual states that the max >plate current is 550mA for the 3-500Z. Obviusly, I was wrong about the >500mA figure. My apologies to Mr. Rauch and his faithful groupies. > >cheers > >- R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. >end > > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > - Bill Aycock --- Persimmon Hill Woodville, Alabama, US 35776 (in the N.E. corner of the State) W4BSG -- Grid EM64vr baycock@HiWAAY.net w4bsg@arrl.net -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From gd0tep@qsl.net Mon Oct 8 18:35:56 2001 From: gd0tep@qsl.net (Andy GD0TEP) Date: Mon, 8 Oct 2001 18:35:56 +0100 Subject: [AMPS] Beer? In-Reply-To: <200110081814.f98IE0Z19671@contesting.com> Message-ID: >>Real beer comes from Deutchland and the Emerald Isle. > >That's fighting talk! A lot of good beer comes from England: a small amount from >Wales and Scotland. And the Isle of Man...! >>"In taste there is no dispute." 73 de Andy -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Mon Oct 8 19:36:49 2001 From: stevek@jmr.com (Steve Katz) Date: Mon, 8 Oct 2001 11:36:49 -0700 Subject: [AMPS] Noises in electrolytic capacitors Message-ID: How did "noises in electrolytic capacitors" evolve into a discussion about beer? I don't know, but I'm glad it did. I think I'll have a beer. WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: 2 [SMTP:2@vc.net] > Sent: Monday, October 08, 2001 11:14 AM > To: Peter Chadwick; @AMPS > Subject: RE: [AMPS] Noises in electrolytic capacitors > > > > > >Rich said: > > > >>Real beer comes from Deutchland and the Emerald Isle. > > > >That's fighting talk! A lot of good beer comes from England: a small > amount > from > >Wales and Scotland. Belgium produces some very good stuff, and the only > >decent Budweiser is from Budvar in the Czech republic. > > > "In taste there is no dispute." > > > cheers, Peter > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. > end > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 8 20:23:13 2001 From: 2@vc.net (2) Date: Mon, 8 Oct 2001 12:23:13 -0700 Subject: [AMPS] SB-220 cooling Message-ID: <200110081923.f98JN5Z21626@contesting.com> > >Well, I resoldered the pin yet again and thoroughly polished the filament >pins, and so far the repair seems to be holding. The socket seems to be >reasonably tight on the filament pins, so I hope it's not socket >replacement time yet. > To tighten the clip spring, slide it off, bend a bit, and snap it back on. Even though a socket feels tight when unplugging/plugging a tube, one pin could still be not tight. A good way to check a socket for tightness is with a single 3-500Z pin soldered to 4 or so inches of #10 Cu wire, one pin at a time. , >This raises a question, though -- I had assumed that the main source of the >heat that melts the pins was heat dissipated inside the tube element. Now >I'm wondering whether it may not be simple resistive heating from imperfect >contact between the pins and the socket. Anyone have a view on which >effect predominates? > Filament power alone gets pins 1 and 5 hot enough to melt solder, sans-forced air cooling. >I also notice that my amp seems to breathe a LOT better with the case off >(but the cage and deflector plate in place, of course. A foot away from >the top of the cage I can feel a nice breeze. Perhaps I should just leave >it this way (without the outer case) for contest use. comments? Without obstructions, the stock 220 air cooling is enough for all except berserko 11m speech processing -- provided the fan motor is periodically oiled. > cheers, Pete - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 8 20:48:31 2001 From: 2@vc.net (2) Date: Mon, 8 Oct 2001 12:48:31 -0700 Subject: [AMPS] An apology Message-ID: <200110081948.f98JmMZ22605@contesting.com> > >Rich- when you are wrong, and caught, you (once in a blue moon) admit it. // Have you perchance read *Animal Farm* by George Orwell? (a.k.a. Eric Arthur Blair, 1903-1950) What is the max plate-current rating of a 3-500Z? cheers >When you try to be a horses A**, you do a better, more complete, job. > >Bill-W4BSG > > >At 11:14 AM 10/8/01 -0700, you wrote: >> >>Today, YS1XS informed me that the AL-80A manual states that the max >>plate current is 550mA for the 3-500Z. Obviusly, I was wrong about the >>500mA figure. My apologies to Mr. Rauch and his faithful groupies. >> >>cheers >> >>- R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jimr.reid@verizon.net Mon Oct 8 21:29:39 2001 From: jimr.reid@verizon.net (Jim Reid) Date: Mon, 8 Oct 2001 10:29:39 -1000 Subject: [AMPS] CW/SSB Tune Up References: <000f01c1487a$966388c0$a1040304@vz.dsl.genuity.net> Message-ID: <000701c15037$f9a8d7e0$a1040304@vz.dsl.genuity.net> Hi, Consider: Tune up my linear using 50 wpm "dits" for 1500 watts peak output as read on my VFD peak reading bargraph/ digital meter, CW mode. This into a Bird dummy load. Now, switch to SSB, max out, without really yelling into the mike is around 1000 watts peak reading. Question: leave things just as they are now, or increase the drive power to bring the SSB peak readings back up near 1500 watts? If I do that, then switch back to the CW mode, the peak out is way high, hi. Someone posted a few days ago that when tuning up a triode linear for peak out on SSB, one should call a steady "Helloooooo", or I have also heard "woof, woof", hi. That this procedure is the "proper" SSB peak out tune up procedure. Is it?? Then when switching to your properly adjusted antenna "system", that is the rig set up does see a 50 ohm load, all will be well with your amp set up and highest legal peak output power. What is proper set up tune up process for max legal out on each mode? 73, Jim KH7M -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From baycock@HIWAAY.NET Mon Oct 8 21:31:43 2001 From: baycock@HIWAAY.NET (Bill Aycock) Date: Mon, 08 Oct 2001 15:31:43 -0500 Subject: [AMPS] An apology In-Reply-To: <200110081948.f98JmMjg020526@mail.hiwaay.net> Message-ID: <3.0.5.32.20011008153143.01a41d00@HIWAAY.NET> At 12:48 PM 10/8/01 -0700, you wrote: >> >>Rich- when you are wrong, and caught, you (once in a blue moon) admit it. > >// Have you perchance read *Animal Farm* by George Orwell? (a.k.a. Eric >Arthur Blair, 1903-1950) Yes- I read it the first time , many years ago, and have read parts since (usually to check supposed 'quotations'. >What is the max plate-current rating of a 3-500Z? My only reference (Not one you would trust) says 400mA.-- So what? > >cheers > >>When you try to be a horses A**, you do a better, more complete, job. >> >>Bill-W4BSG >> > - Bill Aycock --- Persimmon Hill Woodville, Alabama, US 35776 (in the N.E. corner of the State) W4BSG -- Grid EM64vr baycock@HiWAAY.net w4bsg@arrl.net -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From bjk@ihug.co.nz Mon Oct 8 21:46:07 2001 From: bjk@ihug.co.nz (Barry Kirkwood) Date: Tue, 9 Oct 2001 09:46:07 +1300 Subject: [AMPS] Beer? References: Message-ID: <082e01c1503a$421ce640$30d0adcb@ihug.co.nz> Beer comes in two varieties: Mass produced chemical piss which induces intense brand loyalty in those stupid enough to consume it. (obviously causes insanity) e.g Coors, Bud (or in ZL: Lion or DB) Then there the world of finely crafted brews. Excellent beer is made in the Spanish world as well as in Eu. Also some very good examples in East Asia. Pity they never learned how to make beer in North America. Drinkable wine can sometimes be found there, however. 73 end Barry Kirkwood PhD ZL1DD Signal Hill Homestay 66 Cory Road Palm Beach Waiheke Island 1240 NEW ZEALAND www.waiheke.co.nz/signal.htm ----- Original Message ----- From: Andy GD0TEP To: @AMPS Sent: Tuesday, 09 October, 2001 6:35 AM Subject: RE: [AMPS] Beer? > > >>Real beer comes from Deutchland and the Emerald Isle. > > > >That's fighting talk! A lot of good beer comes from England: a small amount > from > >Wales and Scotland. > > And the Isle of Man...! > > >>"In taste there is no dispute." > > 73 de Andy > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w6frmarv@dslextreme.com Mon Oct 8 22:09:34 2001 From: w6frmarv@dslextreme.com (Marv Gonsior) Date: Mon, 08 Oct 2001 14:09:34 -0700 Subject: [AMPS] Running Time Meters FS Message-ID: <5.1.0.14.2.20011008133158.01f9fd40@mail.dslextreme.com> --=====================_2340773==_.ALT Content-Type: text/plain; charset="us-ascii"; format=flowed Gentlemen: I have for sale the following new, except as noted, running time meters, All read hours to 0.1 hour and priced plus shipping. 2 GE 120VAC, 60Hz, resettable mounts in a 2 1/4" hole, square, white face. $30 ea. 1 General Time, 28VDC, Mounts in 2 1/16" hole, round face $20 1 Electrodynamics, 5VDC, mini, mounts in 3/4" hole $20 1 Electrodynamics, 10 to 34VDC 11/16" mounting hole w/2 7/8" face plate, used w/17 hrs. $15 1 Electrodynamics, same as above $20 1 Cramer Co.,120VAC, 60Hz, mounts in 2 1/4" hole, square face $20 1 Hamilton Watch Co. 24VDC, mounts in 2 1/4" hole, round face, used w/2 hrs. $15 If any interest, please reply direct and thanks. 73, Marv, W6FR --=====================_2340773==_.ALT Content-Type: text/html; charset="us-ascii" Gentlemen:

I have for sale the following new, except as noted, running time meters, All read hours to 0.1 hour and priced plus shipping.

2 GE 120VAC, 60Hz, resettable mounts in a 2 1/4" hole, square, white face.   $30 ea.
1 General Time, 28VDC, Mounts in 2 1/16" hole, round face   $20
1 Electrodynamics, 5VDC, mini, mounts in 3/4" hole $20
1 Electrodynamics, 10 to 34VDC 11/16" mounting hole w/2 7/8" face plate, used w/17 hrs. $15
1 Electrodynamics,              same as above $20
1 Cramer Co.,120VAC, 60Hz, mounts in 2 1/4" hole, square face   $20
1 Hamilton Watch Co. 24VDC, mounts in 2 1/4" hole, round face, used w/2 hrs. $15

If any interest, please reply direct and thanks.

73,

Marv, W6FR --=====================_2340773==_.ALT-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Mon Oct 8 22:14:33 2001 From: stevek@jmr.com (Steve Katz) Date: Mon, 8 Oct 2001 14:14:33 -0700 Subject: [AMPS] Beer? Message-ID: Obviously you've never had the really good American beers, since they're not exported at all. "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Barry Kirkwood [SMTP:bjk@ihug.co.nz] > Sent: Monday, October 08, 2001 1:46 PM > To: gd0tep@qsl.net; @AMPS > Subject: Re: [AMPS] Beer? > > > Beer comes in two varieties: > Mass produced chemical piss which induces intense brand loyalty in those > stupid enough to consume it. (obviously causes insanity) e.g Coors, Bud > (or > in ZL: Lion or DB) > Then there the world of finely crafted brews. Excellent beer is made in > the > Spanish world as well as in Eu. Also some very good examples in East Asia. > Pity they never learned how to make beer in North America. > Drinkable wine can sometimes be found there, however. > 73 > > end > Barry Kirkwood PhD ZL1DD > Signal Hill Homestay > 66 Cory Road > Palm Beach > Waiheke Island 1240 > NEW ZEALAND > www.waiheke.co.nz/signal.htm > ----- Original Message ----- > From: Andy GD0TEP > To: @AMPS > Sent: Tuesday, 09 October, 2001 6:35 AM > Subject: RE: [AMPS] Beer? > > > > > > >>Real beer comes from Deutchland and the Emerald Isle. > > > > > >That's fighting talk! A lot of good beer comes from England: a small > amount > > from > > >Wales and Scotland. > > > > And the Isle of Man...! > > > > >>"In taste there is no dispute." > > > > 73 de Andy > > > > > > -- > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > Submissions: amps@contesting.com > > Administrative requests: amps-REQUEST@contesting.com > > Problems: owner-amps@contesting.com > > > > > > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From baycock@HIWAAY.NET Mon Oct 8 22:52:35 2001 From: baycock@HIWAAY.NET (Bill Aycock) Date: Mon, 08 Oct 2001 16:52:35 -0500 Subject: [AMPS] Beer? In-Reply-To: <082e01c1503a$421ce640$30d0adcb@ihug.co.nz> References: Message-ID: <3.0.5.32.20011008165235.01a42a10@HIWAAY.NET> Barry- I object- the last time I looked at a map, Canada was a part of NA, and they have a couple of pretty good brews. About the part of NA below the Great Lakes and above the Rio Grande, I tend to agree. However, dont pass Bavaria off as 'inEU'; they do VERY well in this category. Bill-W4BSG At 09:46 AM 10/9/01 +1300, you wrote: > >Beer comes in two varieties: >Mass produced chemical piss which induces intense brand loyalty in those >stupid enough to consume it. (obviously causes insanity) e.g Coors, Bud (or >in ZL: Lion or DB) >Then there the world of finely crafted brews. Excellent beer is made in the >Spanish world as well as in Eu. Also some very good examples in East Asia. >Pity they never learned how to make beer in North America. >Drinkable wine can sometimes be found there, however. >73 > >end >Barry Kirkwood PhD ZL1DD - Bill Aycock --- Persimmon Hill Woodville, Alabama, US 35776 (in the N.E. corner of the State) W4BSG -- Grid EM64vr baycock@HiWAAY.net w4bsg@arrl.net -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From KG6DV@cs.com Mon Oct 8 23:49:56 2001 From: KG6DV@cs.com (KG6DV@cs.com) Date: Mon, 8 Oct 2001 18:49:56 EDT Subject: [AMPS] Tuned Input, what me worry Message-ID: <47.121111d9.28f38794@cs.com> --part1_47.121111d9.28f38794_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit There is a lot of discussion lately on how to design a proper tuned input .... that topic and beer have dominated lately. 16 ways to figure the Q of the input circuit, 17 ways to tell a really fine beer. I can understand the value of passing on your knowledge of how to judge a really good beer, but a tuned input ....why bother. I built way too many tuned input circuits till I gave it up ... too much work. I ended up borrowing an approach from the old timers (you here know who you are) remember swamping. A variation on the old method works for me. I use a T-PAD attenuator. The great thing about a T-PAD attenuator is the fact that the load on the output side can swing a great deal while the input will stay put wonderfully. Does this sound like whats needed for an input circuit, it does to me. These transmitting tubes display a fairly large swing in load at different drive levels, not what your exciter needs to see. I design the T-PAD for 1db attenuation, nobody needs to loose a lot of drive power. I size the resistors (non inductive of course) in each of the three legs to handle the dissipation and ..... wallah, you have an input circuit that will show your exciter a nice consistent 50 ohm load. What could be simpler. Its worked for me for years. Now we will all hear whats wrong with this approach .... or maybe just some more great beer theory. Ron KH6DV Kaneohe Hawaii --part1_47.121111d9.28f38794_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit There is a lot of discussion lately on how to design a proper tuned input .... that topic and beer have dominated lately. 16 ways to figure the Q of the input circuit, 17 ways to tell a really fine beer. I can understand the value of passing on your knowledge of how to judge a really good beer, but a tuned input ....why bother.

I built way too many tuned input circuits till I gave it up ... too much work. I ended up borrowing an approach from the old timers (you here know who you are) remember swamping. A variation on the old method works for me. I use a T-PAD attenuator.
The great thing about a T-PAD attenuator is the fact that the load on the output side can swing a great deal while the input will stay put wonderfully. Does this sound like whats needed for an input circuit, it does to me. These transmitting tubes display a fairly large swing in load at different drive levels, not what your exciter needs to see.
I design the T-PAD for 1db attenuation, nobody needs to loose a lot of drive power.
I size the resistors (non inductive of course) in each of the three legs to handle the dissipation and ..... wallah, you have an input circuit that will show your exciter a nice consistent 50 ohm load. What could be simpler. Its worked for me for years.

Now we will all hear whats wrong with this approach .... or maybe just some more great beer theory.

Ron   KH6DV
Kaneohe Hawaii
--part1_47.121111d9.28f38794_boundary-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From bjk@ihug.co.nz Mon Oct 8 23:53:53 2001 From: bjk@ihug.co.nz (Barry Kirkwood) Date: Tue, 9 Oct 2001 11:53:53 +1300 Subject: [AMPS] Tuned Input, what me worry References: <47.121111d9.28f38794@cs.com> Message-ID: <087d01c1504c$1b260e60$30d0adcb@ihug.co.nz> This is a multi-part message in MIME format. ------=_NextPart_000_087A_01C150B9.1155EBE0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I seem to remember the famous Ulrich Rohde publishing a small note in = ?Ham Radio using pad and compensating reactances to tame gg input with = no switching bands. Anybody got a lead on this? 73 end Barry Kirkwood PhD ZL1DD Signal Hill Homestay 66 Cory Road Palm Beach Waiheke Island 1240 NEW ZEALAND www.waiheke.co.nz/signal.htm ----- Original Message -----=20 From: KG6DV@cs.com=20 To: amps@contesting.com=20 Sent: Tuesday, 09 October, 2001 11:49 AM Subject: [AMPS] Tuned Input, what me worry There is a lot of discussion lately on how to design a proper tuned = input .... that topic and beer have dominated lately. 16 ways to figure = the Q of the input circuit, 17 ways to tell a really fine beer. I can = understand the value of passing on your knowledge of how to judge a = really good beer, but a tuned input ....why bother.=20 I built way too many tuned input circuits till I gave it up ... too = much work. I ended up borrowing an approach from the old timers (you = here know who you are) remember swamping. A variation on the old method = works for me. I use a T-PAD attenuator.=20 The great thing about a T-PAD attenuator is the fact that the load on = the output side can swing a great deal while the input will stay put = wonderfully. Does this sound like whats needed for an input circuit, it = does to me. These transmitting tubes display a fairly large swing in = load at different drive levels, not what your exciter needs to see.=20 I design the T-PAD for 1db attenuation, nobody needs to loose a lot of = drive power.=20 I size the resistors (non inductive of course) in each of the three = legs to handle the dissipation and ..... wallah, you have an input = circuit that will show your exciter a nice consistent 50 ohm load. What = could be simpler. Its worked for me for years.=20 Now we will all hear whats wrong with this approach .... or maybe just = some more great beer theory. =20 Ron KH6DV=20 Kaneohe Hawaii=20 ------=_NextPart_000_087A_01C150B9.1155EBE0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
I seem to remember the famous Ulrich Rohde = publishing a small=20 note in ?Ham Radio using pad and compensating reactances to tame gg = input with=20 no switching bands.

Anybody got a lead on this?

73

end
Barry Kirkwood PhD ZL1DD
Signal Hill Homestay
66 Cory=20 Road
Palm Beach
Waiheke Island 1240
NEW ZEALAND
www.waiheke.co.nz/signal.htm=

----- Original Message -----
From:=20 KG6DV@cs.com =
To: amps@contesting.com

Sent: Tuesday, 09 October, 2001 = 11:49=20 AM

Subject: [AMPS] Tuned Input, = what me=20 worry

There is a = lot of=20 discussion lately on how to design a proper tuned input .... that = topic and=20 beer have dominated lately. 16 ways to figure the Q of the input = circuit, 17 ways to tell a really fine beer. I can understand = the value=20 of passing on your knowledge of how to judge a really good beer, but a = tuned=20 input ....why bother.

I built way too many tuned input = circuits till I=20 gave it up ... too much work. I ended up borrowing an approach = from the=20 old timers (you here know who you are) remember swamping. A = variation on=20 the old method works for me. I use a T-PAD attenuator.
The = great=20 thing about a T-PAD attenuator is the fact that the load on the output = side=20 can swing a great deal while the input will stay put wonderfully. Does = this=20 sound like whats needed for an input circuit, it does to me. = These=20 transmitting tubes display a fairly large swing in load at different = drive=20 levels, not what your exciter needs to see.
I design the T-PAD for = 1db=20 attenuation, nobody needs to loose a lot of drive power.
I size = the=20 resistors (non inductive of course) in each of the three legs to = handle the=20 dissipation and ..... wallah, you have an input circuit that will show = your=20 exciter a nice consistent 50 ohm load. What could be simpler. = Its worked=20 for me for years.

Now we will all hear whats wrong with this = approach=20 .... or maybe just some more great beer theory.

Ron=20   KH6DV
Kaneohe Hawaii=20
------=_NextPart_000_087A_01C150B9.1155EBE0-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Mon Oct 8 23:52:33 2001 From: stevek@jmr.com (Steve Katz) Date: Mon, 8 Oct 2001 15:52:33 -0700 Subject: [AMPS] Tuned Input, what me worry Message-ID: Ron, doesn't a 1dB pad only provide 1dB of impedance stabilization? Think about it, and then have a beer. I'll have one, too! "Hang loose," as they say there... WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: KG6DV@cs.com [SMTP:KG6DV@cs.com] > Sent: Monday, October 08, 2001 3:50 PM > To: amps@contesting.com > Subject: [AMPS] Tuned Input, what me worry > > There is a lot of discussion lately on how to design a proper tuned input > .... that topic and beer have dominated lately. 16 ways to figure the Q > of the input circuit, 17 ways to tell a really fine beer. I can > understand the value of passing on your knowledge of how to judge a really > good beer, but a tuned input ....why bother. > > I built way too many tuned input circuits till I gave it up ... too much > work. I ended up borrowing an approach from the old timers (you here know > who you are) remember swamping. A variation on the old method works for > me. I use a T-PAD attenuator. > The great thing about a T-PAD attenuator is the fact that the load on the > output side can swing a great deal while the input will stay put > wonderfully. Does this sound like whats needed for an input circuit, it > does to me. These transmitting tubes display a fairly large swing in load > at different drive levels, not what your exciter needs to see. > I design the T-PAD for 1db attenuation, nobody needs to loose a lot of > drive power. > I size the resistors (non inductive of course) in each of the three legs > to handle the dissipation and ..... wallah, you have an input circuit that > will show your exciter a nice consistent 50 ohm load. What could be > simpler. Its worked for me for years. > > Now we will all hear whats wrong with this approach .... or maybe just > some more great beer theory. > > Ron KH6DV > Kaneohe Hawaii > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From steve@2cls.com Mon Oct 8 23:59:27 2001 From: steve@2cls.com (steveRiley) Date: Mon, 08 Oct 2001 18:59:27 -0400 Subject: [AMPS] Henry Message-ID: <3BC22FCF.A7DA98D3@2cls.com> Anyone else heard that Henry will no longer be making and marketing (for Hams) amplifiers. They will continue to supply parts till they run out??? Steve N8IS -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Tue Oct 9 00:03:39 2001 From: stevek@jmr.com (Steve Katz) Date: Mon, 8 Oct 2001 16:03:39 -0700 Subject: [AMPS] Tuned Input, what me worry Message-ID: For sure, Ron, I've used passive input (swamping) on lots of amps, too. The early ETO/Alpha amps, like my 374, has passive, swamped-input to a trio of 8874's. The old National NCL-2000 was passive input and had to throw away LOTS of power from the NCX-5 or whatever, since it only took ~20W to drive it to 1 kW. Those burned far more than 1dB...I think the NCL-2000 pad was about 6dB or so, so it really did provide about a 4:1 improvement in impedance stability. 73 & drink more beer :) Aloha Steve WB2WIK/6 > This was from a very old W6SAI item. He intended it as a devise to reduce > the power of your old tube, pi-network output exciter so you could load it > up full as it should be to run clean and yet not overdrive your amp. He > explained how to determine which T-PAD you needed to build, 1db, 2db, 3db > or more, depending on how much power you needed to burn. It worked for me > very well. I used it on a 3-1000, 2 single tube 4-1000's and a pair of > 3-400's. > > Ron > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Tue Oct 9 00:06:50 2001 From: stevek@jmr.com (Steve Katz) Date: Mon, 8 Oct 2001 16:06:50 -0700 Subject: [AMPS] Tuned Input, what me worry Message-ID: The best U.S. beers come from microbreweries who don't add any chems, but they don't export and the beer "expires" pretty quickly. It's best to grab it out of the fermentation tank and tap right into that, preferably by installing one's mouth directly beneath the spigot. The only "real American beer" that is produced in volume, in my opinion, is made by Samuel Adams (Boston Brewing) and I don't think they export that, either. In fact, many of the Samuel Adams brews are not sold at all in several States, you have to be close to one of the refineries. Lucky for me, I am. Pass me another brew, will ya, mate? > PS I have enjoyed Anchor Steam etc in the USA , but was depressed how hard > it was to get good US beer in most outlets. > 73 > end > Barry Kirkwood PhD ZL1DD > Signal Hill Homestay > 66 Cory Road > Palm Beach > Waiheke Island 1240 > NEW ZEALAND > www.waiheke.co.nz/signal.htm > ----- Original Message ----- > From: Steve Katz > To: ; > Sent: Tuesday, 09 October, 2001 11:52 AM > Subject: RE: [AMPS] Tuned Input, what me worry > > > > > > Ron, doesn't a 1dB pad only provide 1dB of impedance stabilization? > > > > Think about it, and then have a beer. I'll have one, too! > > > > "Hang loose," as they say there... > > > > WB2WIK/6 > > > > "Each success only buys an admission ticket to a more difficult > problem." -- > > Henry Kissinger > > > > > -----Original Message----- > > > From: KG6DV@cs.com [SMTP:KG6DV@cs.com] > > > Sent: Monday, October 08, 2001 3:50 PM > > > To: amps@contesting.com > > > Subject: [AMPS] Tuned Input, what me worry > > > > > > There is a lot of discussion lately on how to design a proper tuned > input > > > .... that topic and beer have dominated lately. 16 ways to figure the > Q > > > of the input circuit, 17 ways to tell a really fine beer. I can > > > understand the value of passing on your knowledge of how to judge a > really > > > good beer, but a tuned input ....why bother. > > > > > > I built way too many tuned input circuits till I gave it up ... too > much > > > work. I ended up borrowing an approach from the old timers (you here > know > > > who you are) remember swamping. A variation on the old method works > for > > > me. I use a T-PAD attenuator. > > > The great thing about a T-PAD attenuator is the fact that the load on > the > > > output side can swing a great deal while the input will stay put > > > wonderfully. Does this sound like whats needed for an input circuit, > it > > > does to me. These transmitting tubes display a fairly large swing in > load > > > at different drive levels, not what your exciter needs to see. > > > I design the T-PAD for 1db attenuation, nobody needs to loose a lot of > > > drive power. > > > I size the resistors (non inductive of course) in each of the three > legs > > > to handle the dissipation and ..... wallah, you have an input circuit > that > > > will show your exciter a nice consistent 50 ohm load. What could be > > > simpler. Its worked for me for years. > > > > > > Now we will all hear whats wrong with this approach .... or maybe just > > > some more great beer theory. > > > > > > Ron KH6DV > > > Kaneohe Hawaii > > > > > > > -- > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > Submissions: amps@contesting.com > > Administrative requests: amps-REQUEST@contesting.com > > Problems: owner-amps@contesting.com > > > > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Tue Oct 9 00:15:25 2001 From: stevek@jmr.com (Steve Katz) Date: Mon, 8 Oct 2001 16:15:25 -0700 Subject: [AMPS] Henry Message-ID: I hadn't heard this, so I just called Henry on the telephone. They hadn't heard this, either! I asked if they were still making the 2K, 3K, 5K, 8K, etc, and the answer was "Yes, we are." Can I still buy any one of them? "Yes, you can." I guess that answers that. 73 Steve WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: steveRiley [SMTP:steve@2cls.com] > Sent: Monday, October 08, 2001 3:59 PM > To: Amps > Subject: [AMPS] Henry > > > Anyone else heard that Henry will no longer be making and marketing (for > Hams) amplifiers. They will continue to supply parts till they run > out??? Steve N8IS > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From wc6w@juno.com Tue Oct 9 02:59:06 2001 From: wc6w@juno.com (Radio WC6W) Date: Mon, 8 Oct 2001 18:59:06 -0700 Subject: [AMPS] Tuned Input, what me worry References: <47.121111d9.28f38794@cs.com> <087d01c1504c$1b260e60$30d0adcb@ihug.co.nz> Message-ID: <20011008.185906.22838.0.WC6W@juno.com> On Tue, 9 Oct 2001 11:53:53 +1300 "Barry Kirkwood" writes: > >This is a multi-part message in MIME format. > >------=_NextPart_000_087A_01C150B9.1155EBE0 >Content-Type: text/plain; > charset="iso-8859-1" >Content-Transfer-Encoding: quoted-printable > >I seem to remember the famous Ulrich Rohde publishing a small note in >?Ham Radio using pad and compensating reactances to tame gg input with >= >no switching bands. >Anybody got a lead on this? >73 >end >Barry Kirkwood PhD ZL1DD >Signal Hill Homestay >66 Cory Road >Palm Beach >Waiheke Island 1240 >NEW ZEALAND Hi Barry, March ''79 Ham Radio, page 48. Note that there are a couple of printing goofs in the schematic -- the two caps in the top row with values past the decimal point should be marked nF (nanofarads). An interesting idea... considered using it myself once upon a time but... it has some drawbacks. It uses just about as many coils as a classic switched network and they are somewhat larger in value. There is no harmonic suppression. There is no easy way to adjust it in case your math comes out wrong and you need to change the impedance match. 73 & Good evening, Marv WC6W * ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k7fm@teleport.com Tue Oct 9 03:16:33 2001 From: k7fm@teleport.com (Lamb) Date: Mon, 8 Oct 2001 19:16:33 -0700 Subject: [AMPS] Beer? References: <082e01c1503a$421ce640$30d0adcb@ihug.co.nz> Message-ID: <003001c15068$a93c3280$22031ad8@colinlam> My biggest complaint about American beer is that it is served ice cold - thus you cannot tell the flavor whether it is good or bad. As far as I am concerned, there are no bad beers - except for my school roommate's homebrew. Seeing him stirring it in his plastic garbage can, with his armpit under the top of the beer, gave me a bias against his beer. On a hot day, I have enjoyed a Greek beer, a Mexican beer, a Cuban beer and a Fijiian beer. Finished them all. My cw improved after each one - except for the Cuban beer since I was unlicensed there. 73, Colin K7FM -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jimr.reid@verizon.net Tue Oct 9 03:16:12 2001 From: jimr.reid@verizon.net (Jim Reid) Date: Mon, 8 Oct 2001 16:16:12 -1000 Subject: [AMPS] Beer? References: <082e01c1503a$421ce640$30d0adcb@ihug.co.nz> <003001c15068$a93c3280$22031ad8@colinlam> Message-ID: <000701c15068$60b85ac0$a1040304@vz.dsl.genuity.net> > On a hot day, I have enjoyed a.... SE Asian beer, or whenever it came around on a C130, the Philipine San Miguel beer(Sp?)... But that was 34 or so years ago, and in that part of the globe! Very good on a hot, humid afternoon, hi. 73, Jim KH7M -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Tue Oct 9 03:39:36 2001 From: 2@vc.net (2) Date: Mon, 8 Oct 2001 19:39:36 -0700 Subject: [AMPS] An apology Message-ID: <200110090239.f992dRZ01299@contesting.com> > >At 12:48 PM 10/8/01 -0700, you wrote: >>> >>>Rich- when you are wrong, and caught, you (once in a blue moon) admit it. >> >>// Have you perchance read *Animal Farm* by George Orwell? (a.k.a. Eric >>Arthur Blair, 1903-1950) > >Yes- I read it the first time , many years ago, and have read parts since >(usually to check supposed 'quotations'. > // The apology wasn't. >>What is the max plate-current rating of a 3-500Z? > >My only reference (Not one you would trust) says 400mA.-- So what? >> // 3-500Z manufacturers say 400mA. In my experiences, a fresh 3-500Z begins to saturate c. 420mA. However, one amplifier "expert"says tuning up at 550mA is fb and he claims to have a letter from Eimac saying such. He has not produced the letter. My guess is that this letter is unsliced bologna. - cheers, Bill >> >>>When you try to be a horses A**, you do a better, more complete, job. >>> >>>Bill-W4BSG - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Tue Oct 9 03:47:56 2001 From: 2@vc.net (2) Date: Mon, 8 Oct 2001 19:47:56 -0700 Subject: [AMPS] CW/SSB Tune Up Message-ID: <200110090247.f992llZ01650@contesting.com> > >Hi, Consider: > >Tune up my linear using 50 wpm "dits" for 1500 watts >peak output as read on my VFD peak reading bargraph/ >digital meter, CW mode. This into a Bird dummy load. > >Now, switch to SSB, max out, without really yelling >into the mike is around 1000 watts peak reading. > Sounds like the peak reading meter isn't able to read voice peaks but does ok on square waves. >Question: leave things just as they are now, or increase >the drive power to bring the SSB peak readings back up >near 1500 watts? If I do that, then switch back to the >CW mode, the peak out is way high, hi. > tube for max out with max drive, provided that the anode current rating is observed. >Someone posted a few days ago that when tuning up a >triode linear for peak out on SSB, one should call a >steady "Helloooooo", or I have also heard "woof, woof", >hi. That this procedure is the "proper" SSB peak out >tune up procedure. Is it?? It's bandini - except c. 27MHz. >... cheers, Jim - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Tue Oct 9 03:47:59 2001 From: 2@vc.net (2) Date: Mon, 8 Oct 2001 19:47:59 -0700 Subject: [AMPS] Tuned Input, what me worry Message-ID: <200110090247.f992loZ01654@contesting.com> > > >For sure, Ron, I've used passive input (swamping) on lots of amps, too. > >The early ETO/Alpha amps, like my 374, has passive, swamped-input to a trio >of 8874's. The old National NCL-2000 was passive input and had to throw >away LOTS of power from the NCX-5 or whatever, since it only took ~20W to >drive it to 1 kW. > Not if one uses the CT on swamper. >... - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From baycock@HIWAAY.NET Tue Oct 9 03:53:53 2001 From: baycock@HIWAAY.NET (Bill Aycock) Date: Mon, 08 Oct 2001 21:53:53 -0500 Subject: [AMPS] An apology In-Reply-To: <200110090239.f992dRjg010956@mail.hiwaay.net> Message-ID: <3.0.5.32.20011008215353.01a1ae80@HIWAAY.NET> At 07:39 PM 10/8/01 -0700, you wrote: >> SNIP>> >>Yes- I read it the first time , many years ago, and have read parts since >>(usually to check supposed 'quotations'. >> >// The apology wasn't. I did not think, or say, it was I don't know why you brought Orwell into it.. You asked if I had read it- I said yes. If you insist on asking silly questions, at least take the answer at face value. > >// 3-500Z manufacturers say 400mA. In my experiences, a fresh 3-500Z >begins to saturate c. 420mA. However, one amplifier "expert"says tuning >up at 550mA is fb and he claims to have a letter from Eimac saying such. > He has not produced the letter. >My guess is that this letter is unsliced bologna. Like the references (quotes) I have asked you about a couple of times recently? cheers, Bill >>> >>>>When you try to be a horses A**, you do a better, more complete, job. >>>> >>>>Bill-W4BSG > - Bill Aycock --- Persimmon Hill Woodville, Alabama, US 35776 (in the N.E. corner of the State) W4BSG -- Grid EM64vr baycock@HiWAAY.net w4bsg@arrl.net -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From nospam4me@juno.com Tue Oct 9 04:17:03 2001 From: nospam4me@juno.com (skipp isaham) Date: Mon, 8 Oct 2001 20:17:03 -0700 Subject: [AMPS] caig labs products Message-ID: <20011008.201724.-273309.0.nospam4me@juno.com> - Got a few replies about the Caig Labs goodies. Funny how one can type in the wrong name while knowing the proper label.... the mind just doesn't want to see the mistake right out in front. - The products I mentioned are actually called Caig Labs ProGold DeOxit and the spray can lists for about $17 retail. - Thanks to Phil for posting the stated temp specs below. Extended Temperature Range, -34oC to 200oC - The temp specs are unverified by me, but I do use the compound on high heat contacts. I've always assumed it just cooked off at some elevated temperature. - > P.S. In the audiophile world, ProGold has had some > very positive press. (However allot of high-end audiophile > thinking is Voodoo if you ask me.) - I agree... as a tube audio (guitar and music) amplifier type, I've been touting the product for years. It's the only product I use that will take the crunch out of a volume control to my satisfaction. Then we tube audio nuts can get back to the carbon film, carbon comp vs metal film arguments we so enjoy. - ProGold does the job very well. - cheers skipp ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jimr.reid@verizon.net Tue Oct 9 04:53:49 2001 From: jimr.reid@verizon.net (Jim Reid) Date: Mon, 8 Oct 2001 17:53:49 -1000 Subject: [AMPS] CW/SSB Tune Up References: <20011009024747.PXOA20845.mp007.verizon.net@vcnet.com> Message-ID: <003401c15076$03c09400$a1040304@vz.dsl.genuity.net> Aloha Rich and others who have responded, hope I have the following correct: In response to my question, > >Question: leave things just as they are now, or increase > >the drive power to bring the SSB peak readings back up > >near 1500 watts? Rich wrote: > tune for max out with max drive, provided that the anode > current rating is observed. Ok, hmmmm..... Yes, in my Henry Amplifier manual, Henry publishes a full page of your instructions on the importance of correct amplifier tuning. They indicate that the info is reprinted from the March 1989 QST, an article by you, AG6K. But no specific details! Now, Ok, here is the tricky part. 1. My amp has an Eimac 3CX3000A7 tube. The supply voltage, key up, is about 6200! Unit is a Henry 8K. So per your method, I would set this puppy up for the about 5+kW output on CW into the Bird Coax Resistor, 8890-300 dummy load load, for starters. Presume I would use the 50 wpm dits for this tune up. Would keep tweaking until the maximum output cababilities of the amplifier seem to have been reached. Wow, have no idea how high that might be! Next step written by others: 2. Then adjust the loading control such that the output decreases by about 50-75 watts. Said to lower IMD. 3. Reduce the drive to the amplifier to obtain maximum legal output as seen on your dummy load/peak reading digital meter. Depending upon the band, this would cut the input drive to the amp from about 200 to 275 watts down to about 60 or so, approximately to come down from the 5000+ output to the Bird. I have NEVER had the amp put out such power(5000+W) to the dummy load or anywhere else. I might be afraid to, hi. These 200+ watt drive powers are from Paul Johnson at Henry in the data sheets that came with my amplifier a few years ago. 4. Assuming that your antenna system is 50R +j0, switch to the antenna system. With the tuner between the amp output and the antenna feed, this is possible. 5. You should see very little change in power output as viewed on the peak reading watt meter whether you operate in cw or ssb mode. 6. You can adjust the power output control of the exciter slightly to achieve the maximum legal power output of the amplifier as seen on the in-line peak reading watt meter. Ok, have I got it correct? Bought the 8K a few years ago in order to have very clean, cool, lowest possible distortion and the legal output power. 73, Jim KH7M -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From N7CXI@SiliconPixels.com Tue Oct 9 04:53:42 2001 From: N7CXI@SiliconPixels.com (Jim Barber) Date: Mon, 08 Oct 2001 20:53:42 -0700 Subject: [AMPS] CW/SSB Tune Up In-Reply-To: <200110090247.f992llZ01650@contesting.com> Message-ID: <5.0.2.1.1.20011008204440.020dc7a0@mail.elltel.net> >>Someone posted a few days ago that when tuning up a >>triode linear for peak out on SSB, one should call a >>steady "Helloooooo", or I have also heard "woof, woof", >>hi. That this procedure is the "proper" SSB peak out >>tune up procedure. Is it?? > >It's bandini - except c. 27MHz. Only half kidding here - Try "four, four, four, four" (enunciate) and watch the meter. Out of all the silliness tried, it seems to kick the hardest, at least with my voice, mics, and meters. Jim, N7CXI -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From bjk@ihug.co.nz Tue Oct 9 04:56:15 2001 From: bjk@ihug.co.nz (Barry Kirkwood) Date: Tue, 9 Oct 2001 16:56:15 +1300 Subject: [AMPS] Beer? References: <082e01c1503a$421ce640$30d0adcb@ihug.co.nz> <003001c15068$a93c3280$22031ad8@colinlam> <000701c15068$60b85ac0$a1040304@vz.dsl.genuity.net> Message-ID: <099f01c15076$58e2b4e0$30d0adcb@ihug.co.nz> Yep, San Miguel, fits in both Spanish World and E Asian categories. An excellent example of a quality large production beer. 73 end Barry Kirkwood PhD ZL1DD Signal Hill Homestay 66 Cory Road Palm Beach Waiheke Island 1240 NEW ZEALAND www.waiheke.co.nz/signal.htm ----- Original Message ----- From: Jim Reid To: Lamb ; Barry Kirkwood ; ; @AMPS Sent: Tuesday, 09 October, 2001 3:16 PM Subject: Re: [AMPS] Beer? > > > > On a hot day, I have enjoyed a.... > > SE Asian beer, or whenever it came around on a C130, > the Philipine San Miguel beer(Sp?)... But that was 34 or so > years ago, and in that part of the globe! Very > good on a hot, humid afternoon, hi. > > 73, Jim KH7M > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Tue Oct 9 05:35:12 2001 From: 2@vc.net (2) Date: Mon, 8 Oct 2001 21:35:12 -0700 Subject: [AMPS] CW/SSB Tune Up Message-ID: <200110090435.f994Z4Z04836@contesting.com> > > >Aloha Rich and others who have responded, hope >I have the following correct: > >In response to my question, > >> >Question: leave things just as they are now, or increase >> >the drive power to bring the SSB peak readings back up >> >near 1500 watts? > >Rich wrote: > >> tune for max out with max drive, provided that the anode >> current rating is observed. > >Ok, hmmmm..... > >Yes, in my Henry Amplifier manual, Henry publishes a full page >of your instructions on the importance of correct amplifier >tuning. They indicate that the info is reprinted from the March >1989 QST, an article by you, AG6K. But no specific details! > >Now, Ok, here is the tricky part. > >1. My amp has an Eimac 3CX3000A7 >tube. The supply voltage, key up, is about 6200! Unit is >a Henry 8K. So per your method, I would set this puppy up >for the about 5+kW output on CW into the Bird Coax Resistor, >8890-300 dummy load load, for starters. > For starters, you need at least 450w drive. PEP out should be around 9 assuming 60% efficiency. >Presume I would use the 50 wpm dits for this tune up. Would >keep tweaking until the maximum output cababilities >of the amplifier seem to have been reached. Wow, >have no idea how high that might be! > It's a bunch with 6kVDC. >Next step written by others: > > 2. Then adjust the loading control such that the output > decreases by about 50-75 watts. Said to lower IMD. > Not helpful with this bottle because the IMD c, 16db better than the cleanest transceiver. > 3. Reduce the drive to the amplifier to obtain maximum >legal output as seen on your dummy load/peak reading digital > meter. Doing such be reducing mic. gain is best. > >Depending upon the band, this would cut the input drive to the >amp from about 200 to 275 watts down to about 60 or so, >approximately to come down from the 5000+ output to the Bird. > >I have NEVER had the amp put out such power(5000+W) to the >dummy load or anywhere else. I might be afraid to, hi. 5 out is no big deal, It's not even one S-unit more than the legal limit. > These 200+ watt drive powers are from Paul Johnson at Henry in >the data sheets that came with my amplifier a few years ago. > >4. Assuming that your antenna system is 50R +j0, switch > to the antenna system. > >With the tuner between the amp output and the antenna feed, this >is possible. > >5. You should see very little change in power output as > viewed on the peak reading watt meter whether you operate > in cw or ssb mode. > True - with a resonant choke PS. >6. You can adjust the power output control of the exciter > slightly to achieve the maximum legal power output of the > amplifier as seen on the in-line peak reading watt meter. > >Ok, have I got it correct? Bought the 8K a few years ago in >order to have very clean, cool, lowest possible distortion and >the legal output power. > Sure, but one should not run less power than is needed to communicate. If it takes 9 to rise above jammers/sociopaths, that's just fine. "Speak softly and carry a big stick." cheers, Jim - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Jan.E.Holm@telia.se Tue Oct 9 06:54:30 2001 From: Jan.E.Holm@telia.se (Jan.E.Holm@telia.se) Date: Tue, 9 Oct 2001 07:54:30 +0200 Subject: [AMPS] Re: Tuned Input, what me worry Message-ID: We can buy the Samuel Adams in Sweden, I buy it now and then, it�s ok but I rather get the stuff from G, DL and OK land where they also make some excelent beer. Talking about Samuel, if you want to get good beer get the Samuel Smith from England. 73, Jim SM2EKM PS: Molson I can drink but the rest of the North American chemical piss water I can do without, I used to dring Coors back in the seventies but I think I can do without it these days. 73, Jim SM2EKM PS again: Beats me what this had to do with tuned input!!, Now if I only could get a new bandswitch waffer for my old SB-220 I sure would be in business again. ------------------------------------------------------------------------ --------------------- -----Ursprungligt meddelande----- Fr�n: stevek@jmr.com [SMTP:stevek@jmr.com] Skickat: den 9 oktober 2001 01:07 Till: bjk@ihug.co.nz Kopia: amps@contesting.com �mne: RE: [AMPS] Tuned Input, what me worry The best U.S. beers come from microbreweries who don't add any chems, but they don't export and the beer "expires" pretty quickly. It's best to grab it out of the fermentation tank and tap right into that, preferably by installing one's mouth directly beneath the spigot. The only "real American beer" that is produced in volume, in my opinion, is made by Samuel Adams (Boston Brewing) and I don't think they export that, either. In fact, many of the Samuel Adams brews are not sold at all in several States, you have to be close to one of the refineries. Lucky for me, I am. Pass me another brew, will ya, mate? > PS I have enjoyed Anchor Steam etc in the USA , but was depressed how hard > it was to get good US beer in most outlets. > 73 > end > Barry Kirkwood PhD ZL1DD > Signal Hill Homestay > 66 Cory Road > Palm Beach > Waiheke Island 1240 > NEW ZEALAND > www.waiheke.co.nz/signal.htm > ----- Original Message ----- > From: Steve Katz > To: ; > Sent: Tuesday, 09 October, 2001 11:52 AM > Subject: RE: [AMPS] Tuned Input, what me worry > > > > > > Ron, doesn't a 1dB pad only provide 1dB of impedance stabilization? > > > > Think about it, and then have a beer. I'll have one, too! > > > > "Hang loose," as they say there... > > > > WB2WIK/6 > > > > "Each success only buys an admission ticket to a more difficult > problem." -- > > Henry Kissinger > > > > > -----Original Message----- > > > From: KG6DV@cs.com [SMTP:KG6DV@cs.com] > > > Sent: Monday, October 08, 2001 3:50 PM > > > To: amps@contesting.com > > > Subject: [AMPS] Tuned Input, what me worry > > > > > > There is a lot of discussion lately on how to design a proper tuned > input > > > .... that topic and beer have dominated lately. 16 ways to figure the > Q > > > of the input circuit, 17 ways to tell a really fine beer. I can > > > understand the value of passing on your knowledge of how to judge a > really > > > good beer, but a tuned input ....why bother. > > > > > > I built way too many tuned input circuits till I gave it up ... too > much > > > work. I ended up borrowing an approach from the old timers (you here > know > > > who you are) remember swamping. A variation on the old method works > for > > > me. I use a T-PAD attenuator. > > > The great thing about a T-PAD attenuator is the fact that the load on > the > > > output side can swing a great deal while the input will stay put > > > wonderfully. Does this sound like whats needed for an input circuit, > it > > > does to me. These transmitting tubes display a fairly large swing in > load > > > at different drive levels, not what your exciter needs to see. > > > I design the T-PAD for 1db attenuation, nobody needs to loose a lot of > > > drive power. > > > I size the resistors (non inductive of course) in each of the three > legs > > > to handle the dissipation and ..... wallah, you have an input circuit > that > > > will show your exciter a nice consistent 50 ohm load. What could be > > > simpler. Its worked for me for years. > > > > > > Now we will all hear whats wrong with this approach .... or maybe just > > > some more great beer theory. > > > > > > Ron KH6DV > > > Kaneohe Hawaii > > > > > > > -- > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > Submissions: amps@contesting.com > > Administrative requests: amps-REQUEST@contesting.com > > Problems: owner-amps@contesting.com > > > > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com <> -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Tue Oct 9 07:14:40 2001 From: philk5pc@tyler.net (Phil Clements) Date: Tue, 9 Oct 2001 01:14:40 -0500 Subject: [AMPS] CW/SSB Tune Up References: <200110090435.f994Z4Z04836@contesting.com> Message-ID: <004101c15089$af735f40$ac084c42@phil> > > 2. Then adjust the loading control such that the output > > decreases by about 50-75 watts. Said to lower IMD. > > > Not helpful with this bottle because the IMD c, 16db better than the > cleanest transceiver. 2nd harmonic is down c. 60 db and third order better than -35 db on this puppy. (8-K Ultra) The beauty is that since the tune C's are fixed door knobs and the Pi and L coils are ganged together with a chain drive, the above numbers are easily obtained on any frequency from 1.8-30 mhz by just tuning for max. suds. We should all be so clean and lucky, Jim! (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From KG6DV@cs.com Tue Oct 9 07:15:16 2001 From: KG6DV@cs.com (KG6DV@cs.com) Date: Tue, 9 Oct 2001 02:15:16 EDT Subject: [AMPS] Tuned Beer Input Message-ID: <44.146b6136.28f3eff4@cs.com> --part1_44.146b6136.28f3eff4_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Here in Hawaii the biggest selling beer is: Bud for the under 300Lb set and .... Bud lite for the over 300Lb set. ....Really, I kid you not. The locals consume shiploads of the stuff, it runs through you faster than a Honolulu marathon runner. I think Budwiser Hawaii's motto is "You dont buy our beer, You rent it" There was a locally brewed beer, PRIMO but its defunct now. Good imported beer is the exception here, not the rule. Its not a huge seller, most stores have imports and a good variety but it sells slowly. visit Hawaii .... bring beer. By the way we could use some tourists, You wouldnt believe the beaches, mostly empty. The airlines have started to cut ticket rates to stimulate business but I havent noticed the hotels here joining in. No cuts in beer prices noticed either ......did I mention tuned inputs .....no, oh well, steve pass me another beer, please. Ron KH6DV --part1_44.146b6136.28f3eff4_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit Here in Hawaii the biggest selling beer is:
             Bud for the under 300Lb set and ....
             Bud lite for the over 300Lb set. ....Really, I kid you not.

The locals consume shiploads of the stuff, it runs through you faster than a Honolulu
marathon runner. I think Budwiser Hawaii's motto is "You dont buy our beer, You rent it"   There was a locally brewed beer, PRIMO but its defunct now. Good imported beer is the exception here, not the rule. Its not a huge seller, most stores have imports and a good variety but it sells slowly. visit Hawaii .... bring beer. By the way we could use some tourists, You wouldnt believe the beaches, mostly empty. The airlines have started to cut ticket rates to stimulate business but I havent noticed the hotels here joining in. No cuts in beer prices noticed either ......did I mention tuned inputs .....no, oh well, steve pass me another beer, please.

Ron KH6DV
--part1_44.146b6136.28f3eff4_boundary-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From g8gsq@qsl.net Tue Oct 9 07:40:05 2001 From: g8gsq@qsl.net (Steve Thompson) Date: Tue, 9 Oct 2001 07:40:05 +0100 Subject: [AMPS] CW/SSB Tune Up Message-ID: <004001c1508d$3bc595a0$e5037ad5@jackie> -----Original Message----- From: Jim Barber To: amps@contesting.com Date: 09 October 2001 04:57 Subject: Re: [AMPS] CW/SSB Tune Up > > >>>Someone posted a few days ago that when tuning up a >>>triode linear for peak out on SSB, one should call a >>>steady "Helloooooo", or I have also heard "woof, woof", >>>hi. That this procedure is the "proper" SSB peak out >>>tune up procedure. Is it?? >> >>It's bandini - except c. 27MHz. > >Only half kidding here - Try "four, four, four, four" (enunciate) >and watch the meter. Out of all the silliness tried, it seems >to kick the hardest, at least with my voice, mics, and meters. Some years ago, a friend in the mobile radio trade told me that 'five five five....' gave the highest mod index when checking links and sets. Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From g8gsq@qsl.net Tue Oct 9 07:48:10 2001 From: g8gsq@qsl.net (Steve Thompson) Date: Tue, 9 Oct 2001 07:48:10 +0100 Subject: [AMPS] Tuned Input, what me worry Message-ID: <006b01c1508e$5cbf3ee0$e5037ad5@jackie> -----Original Message----- From: Steve Katz To: 'KG6DV@cs.com' ; amps@contesting.com Date: 09 October 2001 00:03 Subject: RE: [AMPS] Tuned Input, what me worry > >Ron, doesn't a 1dB pad only provide 1dB of impedance stabilization? > >Think about it, and then have a beer. I'll have one, too! Nonono, beer first! Anyway, a 1dB pad provides a 2dB improvement - drive power goes through the pad, some or all gets reflected, goes through the pad again before the driver sees it. With 3 dB pad, you can't get worse than 3:1 VSWR, even if the output end is open/short/any phase. A 6dB pad guarantees you about 2:1 max. Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Tue Oct 9 07:31:10 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Tue, 9 Oct 2001 07:31:10 +0100 Subject: [AMPS] Tuned Input, what me worry Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A945@excalibur.swindon.msl.mitel.com> Steve said; >the beer "expires" pretty quickly. A good 'beer' doesn't. In the 16 and 1700's it was common, as country landowner, to 'lay down' a barrel of strong 'ale' on the birth of one's first son, to be broached by all the tenants of the estate when he reached 21........ 'Ale' and 'beer' being used synonomously, although one definition is that ale doesn't have hops and beer does. The hops help it keep. Some of my best home brews (beer, not amps!) were really excellent after 5 years. They may have been even better after longer - just that they didn't last! OTOH, some of my amps have been nearly 20 years in maturation - and still aren't there....... 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ko4nrbs@yahoo.com Tue Oct 9 07:41:58 2001 From: ko4nrbs@yahoo.com (Bill Smith) Date: Mon, 8 Oct 2001 23:41:58 -0700 (PDT) Subject: [AMPS] T Pad Attenuators Message-ID: <20011009064158.6241.qmail@web20501.mail.yahoo.com> In my quest to learn as much as I can about amplifiers I ran across information on T Pad Attenuators used instead of Pi Nets for amplifier input impedance matching. Having just learned how to calcualate Pi Net component values I jumped right in with T Pads. I do have a few questions about the data called for in the software calculators: 1. Is Source Resistance the amp's Plate Load Resistance? 2. Is Load Resistance the output impedance? (50 ohm antenna input?) 3. What Attenuation value in decibels is to be used? Thanks and 73, Bill Smith KO4NR ===== Bill Smith KO4NR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From nospam4me@juno.com Tue Oct 9 07:53:55 2001 From: nospam4me@juno.com (skipp isaham) Date: Mon, 8 Oct 2001 23:53:55 -0700 Subject: [AMPS] re: Airpax Breaker Switches Message-ID: <20011008.235456.-205149.2.nospam4me@juno.com> - I replace a considerable amount of Airpax Breaker Switch units which are cycled on a semi frequent basis. Relative to other brands of similar breaker switches, they fail quite a bit more often. - For the above reason, I don't use them in my new circuit designs. - It wouldn't bother me too much, but they are expensive to replace in existing circuits and I'm told by a friend NASA used them in the space shuttles when he worked there. - cheers skipp ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Tue Oct 9 07:58:03 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Tue, 9 Oct 2001 07:58:03 +0100 Subject: [AMPS] Tuned Input, what me worry Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A946@excalibur.swindon.msl.mitel.com> According to Pappenfus et al., the tank circuit plus the feed cable plus the output network of the driver should be of such length as to make the driver for a g-g stage appear as a constant voltage source. By making the total electrical length a suitable multiple of 90 degrees, this can be achieved without the phase distortion that would be introduced by a varying load on a non integral quarter wave transmission line. The exact length (even or odd multiple of 90 degrees) will depend on whether or not the driver is a voltage or current source. Again, according to Pappenfus, a tetrode with r-f voltage feedback approaches a constant voltage source. >From this viewpoint, then, the actual network doesn't appear to matter. In another part of the same reference, the cathode tank supplies power 'during the negative half of the cathode r-f voltage swing'. It also says that if the transmission line length between the output of the driver pi network and the cathode is short (<1/20 wavelength) the output capacitor of the pi 'then provides the low capacitive reactance from the amplifier cathode to ground for the lower harmonic frequencies'. This agrees with Tom's point about using a cathode tank that's a pi. A staright forward pad will be good news for the driver, in that the input impedance swing is limited, but I don't see how it helps maintain the sinusoidal drive at the cathode. A parallel tuned circuit will do this, and provide the low impedance to ground for the harmonics, although the values may be a bit large on the lower bands - and the current ratings required in the capacitors. Of course, in all this, there's a big difference between that which is theoretically the most perfect, that which is in practice totally acceptable, and that which is a real no-no. As the techniques that produce the results vary from design to design, some of the 'tablets of stone' may prove at the end of the day to be rather crumbly......... 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Tue Oct 9 08:02:36 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Tue, 9 Oct 2001 08:02:36 +0100 Subject: [AMPS] SB-220 cooling Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A947@excalibur.swindon.msl.mitel.com> FWIW, on 4-250As and similar, (same filament structure as the 3-500Z), not being careful about cooling the filament seals has led to trouble in my experience. Including one military rig where it was considered usual to change tubes after as little as 250 hours of filament life because solder came off the pins. I use a muffin fan blowing on each tube socket, and a large fan 'upstairs' for the envelopes and plate seals: touch wood, no problems. Rich is quite right about the sockets, too. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Tue Oct 9 10:46:35 2001 From: 2@vc.net (2) Date: Tue, 9 Oct 2001 02:46:35 -0700 Subject: [AMPS] CW/SSB Tune Up Message-ID: <200110090946.f999kPZ08990@contesting.com> > > >-----Original Message----- >From: Jim Barber >To: amps@contesting.com >Date: 09 October 2001 04:57 >Subject: Re: [AMPS] CW/SSB Tune Up > > >> >> >>>>Someone posted a few days ago that when tuning up a >>>>triode linear for peak out on SSB, one should call a >>>>steady "Helloooooo", or I have also heard "woof, woof", >>>>hi. That this procedure is the "proper" SSB peak out >>>>tune up procedure. Is it?? >>> >>>It's bandini - except c. 27MHz. >> >>Only half kidding here - Try "four, four, four, four" (enunciate) >>and watch the meter. Out of all the silliness tried, it seems >>to kick the hardest, at least with my voice, mics, and meters. >Some years ago, a friend in the mobile radio trade told me that 'five five >five....' gave the highest mod index when checking links and sets. > // Multitone modulation tuneup requires an oscilloscope. Pulsed single tone tuneup does not. cheers, Steve - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From oz1pif@get2net.dk Tue Oct 9 09:50:18 2001 From: oz1pif@get2net.dk (Peter Frenning, OZ1PIF) Date: Tue, 9 Oct 2001 10:50:18 +0200 Subject: [AMPS] Beer? References: Message-ID: <001101c1509f$6c5645e0$0100a8be@oz1pif> I can certainly recommend "Anchor Steam", unfortunately only available in the S.F. Bay Area. Vy 73 de OZ1PIF, Peter New DXpedition to Greenland for CQWW! See: http://www.qsl.net/xp1ab ********** OZ1PIF ************** email: oz1pif(no-spam-filler)@get2net.dk http://hjem.get2net.dk/oz1pif Shack Ph. +45 4619 3208 Snailmail: Peter Frenning Ternevej 23 DK-4130 Viby Sj. Denmark *********************************** ----- Original Message ----- From: "Steve Katz" To: "'Barry Kirkwood'" ; ; "@AMPS" Sent: Monday, October 08, 2001 11:14 PM Subject: RE: [AMPS] Beer? > > Obviously you've never had the really good American beers, since they're not > exported at all. > > "Each success only buys an admission ticket to a more difficult problem." -- > Henry Kissinger > > > -----Original Message----- > > From: Barry Kirkwood [SMTP:bjk@ihug.co.nz] > > Sent: Monday, October 08, 2001 1:46 PM > > To: gd0tep@qsl.net; @AMPS > > Subject: Re: [AMPS] Beer? > > > > > > Beer comes in two varieties: > > Mass produced chemical piss which induces intense brand loyalty in those > > stupid enough to consume it. (obviously causes insanity) e.g Coors, Bud > > (or > > in ZL: Lion or DB) > > Then there the world of finely crafted brews. Excellent beer is made in > > the > > Spanish world as well as in Eu. Also some very good examples in East Asia. > > Pity they never learned how to make beer in North America. > > Drinkable wine can sometimes be found there, however. > > 73 > > > > end > > Barry Kirkwood PhD ZL1DD > > Signal Hill Homestay > > 66 Cory Road > > Palm Beach > > Waiheke Island 1240 > > NEW ZEALAND > > www.waiheke.co.nz/signal.htm > > ----- Original Message ----- > > From: Andy GD0TEP > > To: @AMPS > > Sent: Tuesday, 09 October, 2001 6:35 AM > > Subject: RE: [AMPS] Beer? > > > > > > > > > > >>Real beer comes from Deutchland and the Emerald Isle. > > > > > > > >That's fighting talk! A lot of good beer comes from England: a small > > amount > > > from > > > >Wales and Scotland. > > > > > > And the Isle of Man...! > > > > > > >>"In taste there is no dispute." > > > > > > 73 de Andy > > > > > > > > > -- > > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > > Submissions: amps@contesting.com > > > Administrative requests: amps-REQUEST@contesting.com > > > Problems: owner-amps@contesting.com > > > > > > > > > > > > > > -- > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > Submissions: amps@contesting.com > > Administrative requests: amps-REQUEST@contesting.com > > Problems: owner-amps@contesting.com > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Tue Oct 9 11:56:01 2001 From: 2@vc.net (2) Date: Tue, 9 Oct 2001 03:56:01 -0700 Subject: [AMPS] Beer? Message-ID: <200110091055.f99AtpZ09909@contesting.com> > >I can certainly recommend "Anchor Steam", unfortunately only available in >the S.F. Bay Area. > >Vy 73 de OZ1PIF, Peter > I live about 500km South of S.F. I have seen Anchor Steam 48-bottle cases for sale here. cheers, Peter - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8AV@aol.com Tue Oct 9 11:58:04 2001 From: W8AV@aol.com (W8AV@aol.com) Date: Tue, 9 Oct 2001 06:58:04 EDT Subject: [AMPS] RE: Beer Message-ID: <12e.5ba2d7d.28f4323c@aol.com> --part1_12e.5ba2d7d.28f4323c_boundary Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: quoted-printable <<>> That's why I make my own!!!! 73................de Goose, W8AV --part1_12e.5ba2d7d.28f4323c_boundary Content-Type: text/html; charset="ISO-8859-1" Content-Transfer-Encoding: quoted-printable <<<Beer comes in= two varieties:
Mass produced chemical piss which induces intense brand loyalty in those
stupid enough to consume it. (obviously causes insanity) e.g Coors, Bud=20= (or
in ZL: Lion or DB)
Then there=A0 the world of finely crafted brews. Excellent beer is made=20= in the
Spanish world as well as in Eu. Also some very good examples in East Asi= a.
Pity they never learned how to make beer in North America.
Drinkable wine can sometimes be found there, however.
73

end
Barry Kirkwood PhD ZL1DD
>>>

That's why I make my own!!!!

73................de Goose, W8AV --part1_12e.5ba2d7d.28f4323c_boundary-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Tue Oct 9 12:43:29 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Tue, 9 Oct 2001 12:43:29 +0100 Subject: [AMPS] RE: Beer Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A955@excalibur.swindon.msl.mitel.com> Goose said: >That's why I make my own!!!! Another 'home brewer' in more ways than one! Amplifier people and contesters seem to have several things in common - one of them is beer! 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Tue Oct 9 15:27:02 2001 From: stevek@jmr.com (Steve Katz) Date: Tue, 9 Oct 2001 07:27:02 -0700 Subject: [AMPS] Tuned Input, what me worry Message-ID: The problem, Peter, is that to make a good, timely amplifier requires good, timely beer. The projects you've started and not completed were undoubtedly started whilst sober, the worst possible situation. "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Peter Chadwick [SMTP:Peter.Chadwick@zarlink.com] > Sent: Monday, October 08, 2001 11:31 PM > To: 'Barry Kirkwood'; Steve Katz > Cc: 'amps@contesting.com' > Subject: RE: [AMPS] Tuned Input, what me worry > > Steve said; > > >the beer "expires" pretty quickly. > > A good 'beer' doesn't. In the 16 and 1700's it was common, as country > landowner, > to 'lay down' a barrel of strong 'ale' on the birth of one's first son, to > be > broached by all the tenants of the estate when he reached 21........ > > 'Ale' and 'beer' being used synonomously, although one definition is that > ale > doesn't have hops and beer does. The hops help it keep. > > Some of my best home brews (beer, not amps!) were really excellent after 5 > years. They may have been even better after longer - just that they didn't > last! > > OTOH, some of my amps have been nearly 20 years in maturation - and still > aren't > there....... > > 73 > > Peter G3RZP > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Tue Oct 9 15:28:37 2001 From: stevek@jmr.com (Steve Katz) Date: Tue, 9 Oct 2001 07:28:37 -0700 Subject: [AMPS] Tuned Input, what me worry Message-ID: Rather than build resistive pads, which involves calculating and soldering, it's easier to just coil up a bunch of RG58/U and cut it to the right length for the attenuation needed; then, open a beer and relax. WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Steve Thompson [SMTP:g8gsq@qsl.net] > Sent: Monday, October 08, 2001 11:48 PM > To: amps@contesting.com > Subject: Re: [AMPS] Tuned Input, what me worry > > > > -----Original Message----- > From: Steve Katz > To: 'KG6DV@cs.com' ; amps@contesting.com > > Date: 09 October 2001 00:03 > Subject: RE: [AMPS] Tuned Input, what me worry > > > > > >Ron, doesn't a 1dB pad only provide 1dB of impedance stabilization? > > > >Think about it, and then have a beer. I'll have one, too! > Nonono, beer first! > > Anyway, a 1dB pad provides a 2dB improvement - drive power goes through > the > pad, some or all gets reflected, goes through the pad again before the > driver sees it. With 3 dB pad, you can't get worse than 3:1 VSWR, even if > the output end is open/short/any phase. A 6dB pad guarantees you about 2:1 > max. > > Steve > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Tue Oct 9 15:32:59 2001 From: stevek@jmr.com (Steve Katz) Date: Tue, 9 Oct 2001 07:32:59 -0700 Subject: [AMPS] Beer? Message-ID: Yes, we can buy Anchor Steam here in L.A. I was very surprised to hear about Samuel Adams available in Sweden, however. Last I toured their headquarters factory in South Boston (only two years ago), they had a map showing everywhere their beer was available, and Europe wasn't even on the map. I hope they've taken their recipe there and are making it locally, and not shipping it across the ocean. And I hope they relocated some of the yeast from the original batch, since a lot of the magic is there. (They get their hops from Bavaria, anyway, and always did.) WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: 2 [SMTP:2@vc.net] > Sent: Tuesday, October 09, 2001 3:56 AM > To: Peter Frenning, OZ1PIF; Steve Katz; 'Barry Kirkwood'; > gd0tep@qsl.net; @AMPS > Subject: Re: [AMPS] Beer? > > > > >I can certainly recommend "Anchor Steam", unfortunately only available in > >the S.F. Bay Area. > > > >Vy 73 de OZ1PIF, Peter > > > I live about 500km South of S.F. I have seen Anchor Steam 48-bottle > cases for sale here. > > cheers, Peter > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. > end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w8ik@subich.com Tue Oct 9 16:12:17 2001 From: w8ik@subich.com (Joe Subich, K4IK) Date: Tue, 9 Oct 2001 11:12:17 -0400 Subject: [AMPS] Enough with the Beer ... Message-ID: OK, folks. With Will in 3D2/c, I've been handling the administrative stuff here. In the last day or so, I have received several private e-mails complaining about the "off topic" traffic. Although it is better than the personal attacks, the absurd one line responses that don't add to the reflector, and repeated pseudo- science I must agree it is time to terminate the "beer thread." Please QRT with the beer talk or take it off the reflector. 73, ... Joe, K4IK acting administrator -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Tue Oct 9 16:22:54 2001 From: W8JI@contesting.com (Tom Rauch) Date: Tue, 9 Oct 2001 11:22:54 -0400 Subject: [AMPS] Tuned Input Circuit Q In-Reply-To: <000d01c1501b$89091f20$a6084c42@phil> Message-ID: <3BC2DE0E.2225.3E7F297@localhost> > You, Rich, and Eimac like pi networks. No, I "like" ANY network that provides a low impedance from cathode to ground for harmonics of the drive frequency at the cathode of the tube. It doesn't matter what that network is, as long as it bypasses the cathode for harmonics of the plate current waveform and isolates harmonics generated in the tube from the exciter. Creative Electronics, > RF Power Products, ETO-Alpha. myself, and others like > parallel or T networks. That doesn't make it a good choice! Just look at IMD in reviews of amplifiers (and transmitters), and you will see how little attention people pay to building clean systems. While parallel networks are often just as good, T networks are really a very poor choice. They are a system begging for less-than- obtainable IMD or efficiency. You have two basic flavors of T networks, and while one type is a low-pass and will reduce harmonics appearing back at the exciter none of them do a good job of ensuring that cathode doesn't pump around with harmonic energy. If you have to use three components and a DP switch, you might as well do it the most reliable way no matter what you "like". You never know what cable length and exciter someone will use. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Tue Oct 9 16:24:35 2001 From: 2@vc.net (2) Date: Tue, 9 Oct 2001 08:24:35 -0700 Subject: [AMPS] Tuned Input, what me worry Message-ID: <200110091524.f99FOPZ14727@contesting.com> > >Rather than build resistive pads, which involves calculating and soldering, >it's easier to just coil up a bunch of RG58/U and cut it to the right length >for the attenuation needed; then, open a beer and relax. > In my experiences, a longer length of RG-58/U seems to decrease input SWR of G-G amplifiers. However, there is no, single, magic length of coax for the nine HF amateur radio bands. The simplist solution is to use a tetrode (preferably with handles), neutralized, operating in Class AB1. When the grid's variable inductor resonates the grid-C on the operating frequency, SWR is minimal, and the tube is neutralized at the operating frequency. later, Steve cheerz > >"Each success only buys an admission ticket to a more difficult problem." -- >Henry Kissinger > >> -----Original Message----- >> From: Steve Thompson [SMTP:g8gsq@qsl.net] >> Sent: Monday, October 08, 2001 11:48 PM >> To: amps@contesting.com >> Subject: Re: [AMPS] Tuned Input, what me worry >> >> >> >> -----Original Message----- >> From: Steve Katz >> To: 'KG6DV@cs.com' ; amps@contesting.com >> >> Date: 09 October 2001 00:03 >> Subject: RE: [AMPS] Tuned Input, what me worry >> >> >> > >> >Ron, doesn't a 1dB pad only provide 1dB of impedance stabilization? >> > >> >Think about it, and then have a beer. I'll have one, too! >> Nonono, beer first! >> >> Anyway, a 1dB pad provides a 2dB improvement - drive power goes through >> the >> pad, some or all gets reflected, goes through the pad again before the >> driver sees it. With 3 dB pad, you can't get worse than 3:1 VSWR, even if >> the output end is open/short/any phase. A 6dB pad guarantees you about 2:1 >> max. >> >> Steve >> >> >> -- >> FAQ on WWW: http://www.contesting.com/FAQ/amps >> Submissions: amps@contesting.com >> Administrative requests: amps-REQUEST@contesting.com >> Problems: owner-amps@contesting.com > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Tue Oct 9 16:24:37 2001 From: stevek@jmr.com (Steve Katz) Date: Tue, 9 Oct 2001 08:24:37 -0700 Subject: [AMPS] Tuned Input, what me worry Message-ID: Hi Rich, I didn't mean to imply the RG58 needs to be cut to a magic length. Just use a lot of it...an infinite length would create a perfect match to the exciter, wouldn't it? And BTW I was only kidding. It was a way to get in one last and final beer joke...okay, I'm done with that! "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: 2 [SMTP:2@vc.net] > Sent: Tuesday, October 09, 2001 8:25 AM > To: Steve Katz; 'Steve Thompson' > Cc: 'amps@contesting.com' > Subject: RE: [AMPS] Tuned Input, what me worry > > > > >Rather than build resistive pads, which involves calculating and > soldering, > >it's easier to just coil up a bunch of RG58/U and cut it to the right > length > >for the attenuation needed; then, open a beer and relax. > > > In my experiences, a longer length of RG-58/U seems to decrease input SWR > of G-G amplifiers. However, there is no, single, magic length of coax > for the nine HF amateur radio bands. The simplist solution is to use a > tetrode (preferably with handles), neutralized, operating in Class AB1. > When the grid's variable inductor resonates the grid-C on the operating > frequency, SWR is minimal, and the tube is neutralized at the operating > frequency. > > later, Steve > cheerz > > > >"Each success only buys an admission ticket to a more difficult problem." > -- > >Henry Kissinger > > > >> -----Original Message----- > >> From: Steve Thompson [SMTP:g8gsq@qsl.net] > >> Sent: Monday, October 08, 2001 11:48 PM > >> To: amps@contesting.com > >> Subject: Re: [AMPS] Tuned Input, what me worry > >> > >> > >> > >> -----Original Message----- > >> From: Steve Katz > >> To: 'KG6DV@cs.com' ; amps@contesting.com > >> > >> Date: 09 October 2001 00:03 > >> Subject: RE: [AMPS] Tuned Input, what me worry > >> > >> > >> > > >> >Ron, doesn't a 1dB pad only provide 1dB of impedance stabilization? > >> > > >> >Think about it, and then have a beer. I'll have one, too! > >> Nonono, beer first! > >> > >> Anyway, a 1dB pad provides a 2dB improvement - drive power goes through > >> the > >> pad, some or all gets reflected, goes through the pad again before the > >> driver sees it. With 3 dB pad, you can't get worse than 3:1 VSWR, even > if > >> the output end is open/short/any phase. A 6dB pad guarantees you about > 2:1 > >> max. > >> > >> Steve > >> > >> > >> -- > >> FAQ on WWW: http://www.contesting.com/FAQ/amps > >> Submissions: amps@contesting.com > >> Administrative requests: amps-REQUEST@contesting.com > >> Problems: owner-amps@contesting.com > > > >-- > >FAQ on WWW: http://www.contesting.com/FAQ/amps > >Submissions: amps@contesting.com > >Administrative requests: amps-REQUEST@contesting.com > >Problems: owner-amps@contesting.com > > > > > > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. > end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Tue Oct 9 17:10:09 2001 From: 2@vc.net (2) Date: Tue, 9 Oct 2001 09:10:09 -0700 Subject: [AMPS] Enough with the Beer ... Message-ID: <200110091609.f99G9vZ15953@contesting.com> > > >OK, folks. With Will in 3D2/c, I've been handling the administrative >stuff here. In the last day or so, I have received several private >e-mails complaining about the "off topic" traffic. // Why kvetch? Set the e-mail router to trash all e-mail containing the word beer, and the source of their consternation will surely disappear, > >Although it is better than the personal attacks, the absurd one >line responses that don't add to the reflector, and repeated pseudo- >science I must agree it is time to terminate the "beer thread." >Please QRT with the beer talk or take it off the reflector. > // Sounds like Joe could use a couple of Brewskys about now. 'Tis only a hobby, Joe. > Cheers > ... Joe, K4IK > acting administrator - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From N7CXI@SiliconPixels.com Tue Oct 9 17:33:03 2001 From: N7CXI@SiliconPixels.com (Jim Barber) Date: Tue, 09 Oct 2001 09:33:03 -0700 Subject: [AMPS] RE: Beer In-Reply-To: <12e.5ba2d7d.28f4323c@aol.com> Message-ID: <5.0.2.1.1.20011009092957.020df030@mail.elltel.net>
Deeply wounded, sir.
If you ever happen to land in the eastern Washington desert,
try a little micro-brewery called "Grant's", in Yakima. They
have a tan&tar that straightens my spine, anyway.. :-)

Jim, N7CXI

At 03:58 AM 10/9/2001, W8AV@aol.com wrote:

<<<Beer comes in two varieties:
Mass produced chemical piss which induces intense brand loyalty in those
stupid enough to consume it. (obviously causes insanity) e.g Coors, Bud (or
in ZL: Lion or DB)
Then there the world of finely crafted brews. Excellent beer is made in the
Spanish world as well as in Eu. Also some very good examples in East Asia.
Pity they never learned how to make beer in North America.
Drinkable wine can sometimes be found there, however.
73

end
Barry Kirkwood PhD ZL1DD

-- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From tmartin@chartermi.net Tue Oct 9 17:58:26 2001 From: tmartin@chartermi.net (Tom Martin) Date: Tue, 09 Oct 2001 11:58:26 -0500 Subject: [AMPS] The Last Word on Beer Message-ID: <3BC32CB2.70C2B286@chartermi.net> A point of interest: If you had bought $1000.00 worth of Nortel stock one year ago, it would now be worth $49.00. If you had bought $1000.00 worth of Budweiser (the beer, not the stock) one year ago, drank all the beer, then traded in the cans at a Michigan redemption center for the dime deposit, you would have $214.00. Given the current conditions of the economy, my advice is to drink heavily and recycle. 73, Tom W8JWN -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From g8gsq@qsl.net Tue Oct 9 18:53:55 2001 From: g8gsq@qsl.net (Steve Thompson) Date: Tue, 9 Oct 2001 18:53:55 +0100 Subject: [AMPS] Tuned Input, what me worry Message-ID: <002f01c150eb$5df5a1c0$89277ad5@jackie> -----Original Message----- From: Steve Katz To: 'Steve Thompson' Cc: 'amps@contesting.com' Date: 09 October 2001 15:35 Subject: RE: [AMPS] Tuned Input, what me worry >Rather than build resistive pads, which involves calculating and soldering, >it's easier to just coil up a bunch of RG58/U and cut it to the right length >for the attenuation needed; then, open a beer and relax. Only downside is the frequency dependence (there's a joke there somewhere about frequency of opening beer bottles - sorry Joe). You could also go for something like RG316 - PTFE gives the temp/power rating, but you end up with a shorter length and smaller bundle. Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Tue Oct 9 18:45:05 2001 From: stevek@jmr.com (Steve Katz) Date: Tue, 9 Oct 2001 10:45:05 -0700 Subject: [AMPS] Tuned Input, what me worry Message-ID: Yep, I've also used RG188 (.100" TFE), very inexpensive surplus and lots of loss. RG142 and RG400 can handle a few kW and are quite lossy, makes the perfect antenna matcher. Simply install 1000' of it between the amp and the antenna, smooths the load right out. TTFN WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Steve Thompson [SMTP:g8gsq@qsl.net] > Sent: Tuesday, October 09, 2001 10:54 AM > To: Steve Katz > Cc: amps@contesting.com > Subject: Re: [AMPS] Tuned Input, what me worry > > > -----Original Message----- > From: Steve Katz > To: 'Steve Thompson' > Cc: 'amps@contesting.com' > Date: 09 October 2001 15:35 > Subject: RE: [AMPS] Tuned Input, what me worry > > > >Rather than build resistive pads, which involves calculating and > soldering, > >it's easier to just coil up a bunch of RG58/U and cut it to the right > length > >for the attenuation needed; then, open a beer and relax. > Only downside is the frequency dependence (there's a joke there somewhere > about frequency of opening beer bottles - sorry Joe). You could also go > for > something like RG316 - PTFE gives the temp/power rating, but you end up > with > a shorter length and smaller bundle. > > Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From g8gsq@qsl.net Tue Oct 9 19:07:03 2001 From: g8gsq@qsl.net (Steve Thompson) Date: Tue, 9 Oct 2001 19:07:03 +0100 Subject: [AMPS] OT question Message-ID: <005b01c150ed$33af9220$89277ad5@jackie> Sorry for OT, but I guess the knowledge is within this group and I'm lazy. What's the difference between TS830 and TS530? The size appears the same, so it's not beer capacity. Thanks, Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From g8gsq@qsl.net Tue Oct 9 19:08:29 2001 From: g8gsq@qsl.net (Steve Thompson) Date: Tue, 9 Oct 2001 19:08:29 +0100 Subject: [AMPS] Tuned Input, what me worry Message-ID: <006a01c150ed$6ab802c0$89277ad5@jackie> -----Original Message----- From: Steve Katz To: 'Steve Thompson' Cc: amps@contesting.com Date: 09 October 2001 18:53 Subject: RE: [AMPS] Tuned Input, what me worry >Yep, I've also used RG188 (.100" TFE), very inexpensive surplus and lots of >loss. RG142 and RG400 can handle a few kW and are quite lossy, makes the >perfect antenna matcher. Simply install 1000' of it between the amp and the >antenna, smooths the load right out. Sorts out rx overload on 40m too. Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Ian White, G3SEK" References: <000d01c1501b$89091f20$a6084c42@phil> <3BC2DE0E.2225.3E7F297@localhost> Message-ID: <8TSwvpACyzw7EASO@ifwtech.com> Tom Rauch wrote: > >While parallel networks are often just as good, T networks are really a >very poor choice. They are a system begging for less-than- obtainable >IMD or efficiency. > >You have two basic flavors of T networks, and while one type is a low- >pass and will reduce harmonics appearing back at the exciter none of >them do a good job of ensuring that cathode doesn't pump around with >harmonic energy. > Amplifiers for 50 and 144MHz often use what look like L-C-L T-networks because the tube's own input capacitance makes it difficult to design a pi-network with sensible component values. What you actually have is a step-up L-network from 50 ohms, back-to-back with a step-down Pi into the cathode. C2 of the Pi-network is the tube's input capacitance, so the situation isn't quite so bad as it looks on the schematic. 73 from Ian G3SEK Editor, 'The VHF/UHF DX Book' 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.com/g3sek -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Tue Oct 9 19:05:26 2001 From: stevek@jmr.com (Steve Katz) Date: Tue, 9 Oct 2001 11:05:26 -0700 Subject: [AMPS] Tuned Input, what me worry Message-ID: > >Yep, I've also used RG188 (.100" TFE), very inexpensive surplus and lots > of > >loss. RG142 and RG400 can handle a few kW and are quite lossy, makes the > >perfect antenna matcher. Simply install 1000' of it between the amp and > the > >antenna, smooths the load right out. > Sorts out rx overload on 40m too. > [Steve Katz] :: Might do, but if not, try another 1000' > Steve > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ToddRoberts2001@aol.com Tue Oct 9 19:44:22 2001 From: ToddRoberts2001@aol.com (ToddRoberts2001@aol.com) Date: Tue, 9 Oct 2001 14:44:22 EDT Subject: [AMPS] circuit breaker recommendation Message-ID: <7d.1c1afa50.28f49f86@aol.com> Thanks to all who responded to my inquiry about choosing a suitable circuit breaker for a transformer power supply primary circuit. I found an excellent guide on circuit breakers at : www.commercialcontrols.eaton.com/cktbrkr.htm . Click on their Heinemann Circuit Breaker Quick Guide . 73 Todd Roberts WD4NGG . -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Tue Oct 9 19:41:34 2001 From: stevek@jmr.com (Steve Katz) Date: Tue, 9 Oct 2001 11:41:34 -0700 Subject: [AMPS] OT question Message-ID: The beer capacity, while an interesting parametric, is not the issue. The 830S has more versatility than the 530S...I'd recommend you read the on-line technical product reviews on each: http://www.arrl.org/members-only/prodrev/pdf/pr8105.pdf applies to the TS-830S, and http://www.arrl.org/members-only/prodrev/pdf/pr8203.pdf applies to the TS-530S They're good reports. WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Steve Thompson [SMTP:g8gsq@qsl.net] > Sent: Tuesday, October 09, 2001 11:07 AM > To: amps@contesting.com > Subject: [AMPS] OT question > > > Sorry for OT, but I guess the knowledge is within this group and I'm lazy. > What's the difference between TS830 and TS530? > > The size appears the same, so it's not beer capacity. > > Thanks, > > Steve > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Tue Oct 9 20:09:05 2001 From: 2@vc.net (2) Date: Tue, 9 Oct 2001 12:09:05 -0700 Subject: [AMPS] Tuned Input Circuit Q Message-ID: <200110091908.f99J8sZ20985@contesting.com> > > >> You, Rich, and Eimac like pi networks. > >No, I "like" ANY network that provides a low impedance from >cathode to ground for harmonics of the drive frequency at the >cathode of the tube. It doesn't matter what that network is, as long >as it bypasses the cathode for harmonics of the plate current >waveform and isolates harmonics generated in the tube from the >exciter. > // By omitting the aforementioned four-letter word that begins with "R", you might have gotten a less verbose answer. >> Creative Electronics, RF Power Products, ETO-Alpha. myself, and others like >> parallel or T networks. > >That doesn't make it a good choice! Just look at IMD in reviews of >amplifiers (and transmitters), and you will see how little attention >people pay to building clean systems. > // The FCC's Paragraph D says that splatter in a ham-band should not go beyond the band edges, so why make ham stuff as clean as possible? >While parallel networks are often just as good, T networks are >really a very poor choice. They are a system begging for less-than- >obtainable IMD or efficiency. > >You have two basic flavors of T networks, and while one type is a >low-pass and will reduce harmonics appearing back at the exciter >none of them do a good job of ensuring that cathode doesn't pump >around with harmonic energy. > >If you have to use three components and a DP switch, you might >as well do it the most reliable way no matter what you "like". You >never know what cable length and exciter someone will use. // In other word's, Ameritron/MFJ's expert sorta likes low-pass Pi-networks when a Z-transformation is needed -- i.e., the g-g tube's cathode isn't 50-ohms. >73, Tom W8JI cheers - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Tue Oct 9 20:09:07 2001 From: 2@vc.net (2) Date: Tue, 9 Oct 2001 12:09:07 -0700 Subject: [AMPS] Tuned Input, what me worry Message-ID: <200110091908.f99J8tZ20991@contesting.com> > >Hi Rich, > >I didn't mean to imply the RG58 needs to be cut to a magic length. // As I recall, the 5-band Collins 30L-1 recommended a certain length of input coax. Does anyone have info on this? >Just use >a lot of it...an infinite length would create a perfect match to the >exciter, wouldn't it? > // Good point. However 20 - 30 ft. of RG-58/U seems to work ok, has less attenuation, less delay, and it costs less. >And BTW I was only kidding. It was a way to get in one last and final beer >joke...okay, I'm done with that! > // As I see it Beer is a contesting-related topic. I've received phone calls from two persons who currently participate in AMPS who were speaking so loudly they sounded like they were running 30db of speech compression. They were sooooo loud that I could lay the telephone handset down and use it like a speaker-phone. Who knows, perhaps "Anchor Steam powered" would be a significant advantage in ham contesting? cheers, Steves - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Tue Oct 9 21:56:09 2001 From: W8JI@contesting.com (Tom Rauch) Date: Tue, 9 Oct 2001 16:56:09 -0400 Subject: [AMPS] 3-500Z emission saturation In-Reply-To: <3.0.5.32.20011008215353.01a1ae80@HIWAAY.NET> References: <200110090239.f992dRjg010956@mail.hiwaay.net> Message-ID: <3BC32C29.31835.5191AE8@localhost> > I did not think, or say, it was I don't know why you brought Orwell > into it.. You asked if I had read it- I said yes. If you insist on > asking silly questions, at least take the answer at face value. > >// > 3-500Z manufacturers say 400mA. In my experiences, a fresh 3-500Z > >begins to saturate c. 420mA. However, one amplifier "expert"says > tuning >up at 550mA is fb and he claims to have a letter from Eimac > saying such. > He has not produced the letter. >My guess is that > this letter is unsliced bologna. > > Like the references (quotes) I have asked you about a couple of times > recently? Anyone who claims a 3-500Z starts to "saturate" at "c. 420 mA" clearly has no idea what he is saying, or is intentionally giving misinformation. Thoriated tungsten tubes typically begin to show emission limits at 50-100 mA per watt at 1900 degrees C, which places a 15 ampere 5 volt filament at 3.75-7.5 amperes for the beginning point of emission limiting. (source Vacuum Tube Electron Emission, Electronic Designers Handbook 2nd edition section 9-9). The actual fully saturated emission of 3-500Z, where no more current can be draw no matter what the applied voltages are, is in the order of 11 amperes. You can easily understand the "game" when you read step 13 of the AL80A manual which is either ignored or misquoted. Step 13 says "In CW operation drive power is reduced until plate current is 400mA or less." 1.) On one hand, claims are made by a certain person a parasitic can cause enough anode current to "bend filament wires from magnetic fields". 2.) On the other hand, the same person claims he "starts to see current saturation at 420 mA". GOOD tuning instructions tell a person to over-couple the PA (which reduces gain, reduces peak tank voltages, and improves linearity). POOR tuning instructions tell a person to load the PA only to the expected maximum average current, which virtually ensures excessive tank voltages and non-linearity on peaks. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Tue Oct 9 22:03:23 2001 From: stevek@jmr.com (Steve Katz) Date: Tue, 9 Oct 2001 14:03:23 -0700 Subject: [AMPS] 3-500Z emission saturation Message-ID: This is why some people spell it, "auspice," while others spell it "hoss piss." The only problem I find with the AL-80B, other than the borderline workmanship (I had to solder the OPR/STBY switch myself, since the factory was saving on solder at this location) is the incredibly wordy operating instructions -- which warn not to exceed 400mA Ip but then go on to detail ALC adjustments requiring 200mA Ig as a limit set. Really hard to get 200mA Ig without exceeding 400mA Ip, unless the HV PS fails. But, anyway... WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Tom Rauch [SMTP:w8ji@akorn.net] > Sent: Tuesday, October 09, 2001 1:56 PM > To: amps@contesting.com; Bill Aycock > Subject: [AMPS] 3-500Z emission saturation > > > > I did not think, or say, it was I don't know why you brought Orwell > > into it.. You asked if I had read it- I said yes. If you insist on > > asking silly questions, at least take the answer at face value. > >// > > 3-500Z manufacturers say 400mA. In my experiences, a fresh 3-500Z > > >begins to saturate c. 420mA. However, one amplifier "expert"says > > tuning >up at 550mA is fb and he claims to have a letter from Eimac > > saying such. > He has not produced the letter. >My guess is that > > this letter is unsliced bologna. > > > > Like the references (quotes) I have asked you about a couple of times > > recently? > > Anyone who claims a 3-500Z starts to "saturate" at "c. 420 mA" > clearly has no idea what he is saying, or is intentionally giving > misinformation. > > Thoriated tungsten tubes typically begin to show emission limits at > 50-100 mA per watt at 1900 degrees C, which places a 15 ampere > 5 volt filament at 3.75-7.5 amperes for the beginning point of > emission limiting. (source Vacuum Tube Electron Emission, > Electronic Designers Handbook 2nd edition section 9-9). > > The actual fully saturated emission of 3-500Z, where no more > current can be draw no matter what the applied voltages are, is in > the order of 11 amperes. > > You can easily understand the "game" when you read step 13 of > the AL80A manual which is either ignored or misquoted. Step 13 > says "In CW operation drive power is reduced until plate current is > 400mA or less." > > 1.) On one hand, claims are made by a certain person a parasitic > can cause enough anode current to "bend filament wires from > magnetic fields". > > 2.) On the other hand, the same person claims he "starts to see > current saturation at 420 mA". > > GOOD tuning instructions tell a person to over-couple the PA > (which reduces gain, reduces peak tank voltages, and improves > linearity). > > POOR tuning instructions tell a person to load the PA only to the > expected maximum average current, which virtually ensures > excessive tank voltages and non-linearity on peaks. > 73, Tom W8JI > W8JI@contesting.com > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From n4zr@contesting.com Tue Oct 9 22:12:50 2001 From: n4zr@contesting.com (Pete Smith) Date: Tue, 09 Oct 2001 17:12:50 -0400 Subject: [AMPS] SB-220 cooling -- another thought Message-ID: <3.0.5.32.20011009171250.0095ba10@pop.abs.adelphia.net> In my SB-220, at least, the springs that clamp the socket contacts on the pins are very readily removable. The design really looks as if the springs were designed to be changed out if and when they became overheated Assuming the spring clips on the filament pins have been annealed to the point that they will no longer hold tension, that raises a few possibilities: Could I swap one or both (rebent first) for the springs on a grid pin, which presumably have not been through such temperature extremes? Could I seek to retemper the spring clips by heating and quenching? Does anyone have a junked SB-220 or other amp with the same sockets from which you'd be willing to scavenge some non-filament springs? Does anyone know of a source for the clips without buying the whole socket? 73, Pete N4ZR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From yo9fzs@office.deck.ro Tue Oct 9 12:01:01 2001 From: yo9fzs@office.deck.ro (yo9fzs) Date: Tue, 09 Oct 2001 13:01:01 +0200 Subject: [AMPS] Solitron SPF-90 Message-ID: <3BC2D8ED.5E27DFB7@office.deck.ro> Hi all, I have two spare rectifier modules made by Solitron, the SPF-90 and SPF-30 used in a Harris RF-124 PS. Anyone having info about their ratings? Thanks, 73s, Traian -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From bravo@iol.ie Tue Oct 9 23:03:49 2001 From: bravo@iol.ie (John Tait) Date: Tue, 9 Oct 2001 23:03:49 +0100 Subject: [AMPS] Enough with the Beer ... References: Message-ID: <002101c1510e$47cd1860$472b7dc2@johntait> HIC..!! -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From baycock@HIWAAY.NET Tue Oct 9 23:11:38 2001 From: baycock@HIWAAY.NET (Bill Aycock) Date: Tue, 09 Oct 2001 17:11:38 -0500 Subject: [AMPS] Re: 3-500Z emission saturation In-Reply-To: <3BC32C29.31835.5191AE8@localhost> References: <3.0.5.32.20011008215353.01a1ae80@HIWAAY.NET> <200110090239.f992dRjg010956@mail.hiwaay.net> Message-ID: <3.0.5.32.20011009171138.018b8d40@HIWAAY.NET> The same person that is the subject of this: > >1.) On one hand, claims are made by a certain person a parasitic >can cause enough anode current to "bend filament wires from >magnetic fields". > >2.) On the other hand, the same person claims he "starts to see >current saturation at 420 mA". > > This is the same person that believes that low distortion is a bunch of hog wash- witness this quote: >// The FCC's Paragraph D says that splatter in a ham-band should not go >beyond the band edges, so why make ham stuff as clean as possible? And- who will not furnish the references to back up some of the libel he spouts. Bill-W4BSG > - Bill Aycock --- Persimmon Hill Woodville, Alabama, US 35776 (in the N.E. corner of the State) W4BSG -- Grid EM64vr baycock@HiWAAY.net w4bsg@arrl.net -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jimr.reid@verizon.net Wed Oct 10 00:15:51 2001 From: jimr.reid@verizon.net (Jim Reid) Date: Tue, 9 Oct 2001 13:15:51 -1000 Subject: [AMPS] Re: CW/SSB Tune Up References: <200110090435.f994Z4Z04836@contesting.com> <004101c15089$af735f40$ac084c42@phil> Message-ID: <002501c15118$59d23d60$a1040304@vz.dsl.genuity.net> Hi again, And thanks a bunch to the several who have commented and made specific tune up recommendations! Have followed them this morning. Rich, I chickened out at just about 345 watts of drive, hi. The grid current was approaching/bit exceeding 300 mA; Henry manual says to not exceed 350 mA. All of this into the Bird load, of course. Bird 43 with a 5kW slug was of no use, it is way too slow and does not respond to the 50 wpm dits. Anyway I found that once the tune and load controls were at resonance, they did not seem to need to be tweaked as the drive was increased beyond 100 watts or so. Hope this is correct, or perhaps I need better instrumentation to "see" the correct peak output power. But see the next paragraph! I dug out the data sheets which came from Henry when the unit was delivered. Per the factory data, there is a difference in the tune/load settings between 2500 and 5000 watts out. I presume this to be constant Pout, not just peak. For example, on 20 meters (14200 test freq.), the dial calibrations for 100 watts drive, yielding about 2500 watts out, tune is at a dial reading of 155, and the load capacitor at 700 (a 1000 reading would indicated full load C "mesh" or max C). With 200 watts drive, factory data shows tune dial at 160, and the load C is lower, at a dial of 460 or seemingly significantly heavier loading of the output. Maybe I should do this all over again and just use constant key down for the final tweaking. Another interesting point from the Henry manual. The amp has two plate voltage selections. With today's mains voltage here on the island, in the SSB "mode", amp not keyed, the plate voltage sits at about 5800 V. In the CW "mode", the voltage is dropped to about 4300 V. The Henry manual asks that one tune up in the CW mode for max output. THEN switching to the SSB mode higher voltage "As long as your load has not changed, the amplifier should still be in tune. You can fine tune by alternately adjusting TUNE and LOAD while driving the amp with a constant input." Well, maybe all of this fiddling is of no point, as I lower the drive well down before going to the antenna set up! 73, Jim KH7M -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Wed Oct 10 00:15:19 2001 From: stevek@jmr.com (Steve Katz) Date: Tue, 9 Oct 2001 16:15:19 -0700 Subject: [AMPS] Re: CW/SSB Tune Up Message-ID: Sounds like you're trying to fry the fish while they're still in the ocean, there, Jim. WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Jim Reid [SMTP:jimr.reid@verizon.net] > Sent: Tuesday, October 09, 2001 4:16 PM > To: Phil Clements; 2; AMPS > Subject: [AMPS] Re: CW/SSB Tune Up > > > Hi again, > > And thanks a bunch to the several who have commented > and made specific tune up recommendations! Have > followed them this morning. Rich, I chickened out at > just about 345 watts of drive, hi. The grid current was > approaching/bit exceeding 300 mA; Henry manual says > to not exceed 350 mA. All of this into the Bird > load, of course. Bird 43 with a 5kW slug was of no use, > it is way too slow and does not respond to the 50 wpm > dits. > > Anyway I found that once the tune and load controls were > at resonance, they did not seem to need to be tweaked > as the drive was increased beyond 100 watts or so. Hope > this is correct, or perhaps I need better instrumentation > to "see" the correct peak output power. But see the next > paragraph! > > I dug out the data sheets which came from Henry when the > unit was delivered. Per the factory data, there is a difference > in the tune/load settings between 2500 and 5000 watts out. > I presume this to be constant Pout, not just peak. For example, > on 20 meters (14200 test freq.), the dial calibrations for 100 > watts drive, yielding about 2500 watts out, tune is at a dial > reading of 155, and the load capacitor at 700 (a 1000 reading > would indicated full load C "mesh" or max C). With 200 watts > drive, factory data shows tune dial at 160, and the load C is lower, > at a dial of 460 or seemingly significantly heavier loading of > the output. Maybe I should do this all over again and just > use constant key down for the final tweaking. > > Another interesting point from the Henry manual. The amp has > two plate voltage selections. With today's mains voltage here > on the island, in the SSB "mode", amp not keyed, the plate > voltage sits at about 5800 V. In the CW "mode", the voltage > is dropped to about 4300 V. The Henry manual asks that one > tune up in the CW mode for max output. THEN switching to the > SSB mode higher voltage "As long as your load has not changed, > the amplifier should still be in tune. You can fine tune by alternately > adjusting TUNE and LOAD while driving the amp with a > constant input." > > Well, maybe all of this fiddling is of no point, as I lower > the drive well down before going to the antenna set up! > > 73, Jim KH7M > > > > > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Wed Oct 10 01:48:44 2001 From: W8JI@contesting.com (Tom Rauch) Date: Tue, 9 Oct 2001 20:48:44 -0400 Subject: [AMPS] Re: CW/SSB Tune Up In-Reply-To: <002501c15118$59d23d60$a1040304@vz.dsl.genuity.net> Message-ID: <3BC362AC.26564.5EE1311@localhost> > load, of course. Bird 43 with a 5kW slug was of no use, > it is way too slow and does not respond to the 50 wpm > dits. Even if the metering system does not indicate peaks, it is generally good for geting optimum tuning on long pulses. The only requirement is the rise and fall be short compared to the flat time at the top. There is no magic with speed or duty cycle used, except as it relates to average dissipation in the elements. > Anyway I found that once the tune and load controls were > at resonance, they did not seem to need to be tweaked > as the drive was increased beyond 100 watts or so. The load is not resonanted. It sets the anode load impedance. The plate control is used to set resonance. > max C). With 200 watts drive, factory data shows tune dial at 160, > and the load C is lower, at a dial of 460 or seemingly significantly > heavier loading of the output. Maybe I should do this all over again > and just use constant key down for the final tweaking. A pulse should be fine with almost any meter, as long as the rise and fall times are short compared to the on time. The meter does NOT have to indicate peaks to let you tune the PA properly on a string of pulses. > Well, maybe all of this fiddling is of no point, as I lower > the drive well down before going to the antenna set up! Since most exciters have considerable overshoot, it is always a good idea to overload the tank somewhat. You can do that by opening the load control slightly past the point of maximum output at full carrier drive. The plate control should always be peaked for maximum output, unless the manufacturer tells you to do something else because of unstable feedback or something equally odd. Grounded grid amps are really very forgiving, but it is best to load on the heavy side if you do make an error. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jimr.reid@verizon.net Wed Oct 10 02:13:38 2001 From: jimr.reid@verizon.net (Jim Reid) Date: Tue, 9 Oct 2001 15:13:38 -1000 Subject: [AMPS] Re: CW/SSB Tune Up References: <3BC362AC.26564.5EE1311@localhost> Message-ID: <000501c15128$cdd7d3e0$a1040304@vz.dsl.genuity.net> This amp is operating, CW mode, on 14051 right NOW. Will be there putting out about 1500 watts between 0115 and 0140 UTC. This is my CW practice "broadcast". Signal reports/quality invited, if you have time. 73, Jim KH7M -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From g8gsq@qsl.net Wed Oct 10 07:33:26 2001 From: g8gsq@qsl.net (Steve Thompson) Date: Wed, 10 Oct 2001 07:33:26 +0100 Subject: [AMPS] re OT question Message-ID: <006001c15155$7899cd20$d0b97ad5@jackie> Thanks to everyone who replied. Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From fortra@siol.net Wed Oct 10 08:22:20 2001 From: fortra@siol.net (=?iso-8859-1?Q?Nermin_Bajramovi=E6?=) Date: Wed, 10 Oct 2001 09:22:20 +0200 Subject: [AMPS] Re: Tuned Input, what me worry References: Message-ID: <008601c1515c$4d652580$bcbfbdc1@nerminba> Hello Jim, regarding wafer for SB220, try Harbach.com they are selling them for 27$ piece. Good luck, yeah regarding beer, how about Fosters, Carlsberg ( not Elephant beer!) Nermin S58DX -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 10 13:21:58 2001 From: 2@vc.net (2) Date: Wed, 10 Oct 2001 05:21:58 -0700 Subject: [AMPS] 3-500Z emission saturation Message-ID: <200110101221.f9ACLlZ05860@contesting.com> > >> I did not think, or say, it was I don't know why you brought Orwell >> into it.. You asked if I had read it- I said yes. If you insist on >> asking silly questions, at least take the answer at face value. > >// >> 3-500Z manufacturers say 400mA. In my experiences, a fresh 3-500Z >> begins to saturate c. 420mA. However, one amplifier "expert"says >> tuning >up at 550mA is fb and he claims to have a letter from Eimac >> saying such. > He has not produced the letter. >My guess is that >> this letter is unsliced bologna. >> >> Like the references (quotes) I have asked you about a couple of times >> recently? > >Anyone who claims a 3-500Z starts to "saturate" at "c. 420 mA" >clearly has no idea what he is saying, or is intentionally giving >misinformation. > // 420mA was the average current measured. The corresponding peak anode current would have been c. 1.25a. >Thoriated tungsten tubes typically begin to show emission limits at >50-100 mA per watt at 1900 degrees C, // In Care and Feeding ..., Eimac states that the temp is c. 1820�K. , >which places a 15 ampere >5 volt filament at 3.75-7.5 amperes for the beginning point of >emission limiting. (source Vacuum Tube Electron Emission, >Electronic Designers Handbook 2nd edition section 9-9). > // According to the 3-500Z constant current curves, peak currents above 1.2 amperes are progressively non-linear. >The actual fully saturated emission of 3-500Z, where no more >current can be draw no matter what the applied voltages are, is in >the order of 11 amperes. // Agreed, however, this has nothing to do with linear operation. > >You can easily understand the "game" when you read step 13 of >the AL80A manual which is either ignored or misquoted. Step 13 >says "In CW operation drive power is reduced until plate current is >400mA or less." > // Surely. The rub is that a tube that is tuned in its not-linear region is hardly going to be linear when it not readjusted for operation in the linear region. >1.) On one hand, claims are made by a certain person a parasitic >can cause enough anode current to "bend filament wires from >magnetic fields". > // See photograph of bent 3-500Z filament helices on p.15 of "Parasitics Revisited" in the September. 1990 *QST*. >2.) On the other hand, the same person claims he "starts to see >current saturation at 420 mA". > // This was in an SB-1000 with a low-hrs. tube. Mr. Rauch has not yet published the alleged Eimac letter authorizing 500+mA for the 3-500Z. >GOOD tuning instructions tell a person to over-couple the PA >(which reduces gain, reduces peak tank voltages, and improves >linearity). > // However, a well tuned up 3-500Z is already c. 8db cleaner than the avg. transceiver, so no one is likely to notice a couple of db improvement in amplifier IMD. >POOR tuning instructions tell a person to load the PA only to the >expected maximum average current, which virtually ensures >excessive tank voltages and non-linearity on peaks. // Date: 8 Nov 1996 05:45:01 GMT ... (Tom Rauch): >"And then I wrote the RF tank voltage can exceed the dc supply voltage by > several times when the PA is unloaded. ,,," In a SB-220, Anode supply potential is c. 2900VDC. 3 x 2900V= 8700V. Normal tank potential at the Tune-C is c. 2700V-pk. During a worst case scenario, this potential is c. 3600V-pk. At sea-level, the Tune-C's breakdown potential is c.3700v. >73, Tom W8JI >W8JI@contesting.com > cheers - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 10 13:22:01 2001 From: 2@vc.net (2) Date: Wed, 10 Oct 2001 05:22:01 -0700 Subject: [AMPS] Re: 3-500Z emission saturation Message-ID: <200110101221.f9ACLlZ05865@contesting.com> > >The same person that is the subject of this: >> >>1.) On one hand, claims are made by a certain person a parasitic >>can cause enough anode current to "bend filament wires from >>magnetic fields". >> >>2.) On the other hand, the same person claims he "starts to see >>current saturation at 420 mA". >> >> >This is the same person that believes that low distortion is a bunch of hog >wash- witness this quote: > >>// The FCC's Paragraph D says that splatter in a ham-band should not go >>beyond the band edges, so why make ham stuff as clean as possible? >... // This is from one version of Part 97 - which are the FCC rules for ham radio. It is not hogwash. > ... - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 10 13:22:02 2001 From: 2@vc.net (2) Date: Wed, 10 Oct 2001 05:22:02 -0700 Subject: [AMPS] SB-220 cooling -- another thought Message-ID: <200110101221.f9ACLnZ05871@contesting.com> > >In my SB-220, at least, the springs that clamp the socket contacts on the >pins are very readily removable. The design really looks as if the springs >were designed to be changed out if and when they became overheated > >Assuming the spring clips on the filament pins have been annealed to the >point that they will no longer hold tension, that raises a few possibilities: > >Could I swap one or both (rebent first) for the springs on a grid pin, >which presumably have not been through such temperature extremes? > >Could I seek to retemper the spring clips by heating and quenching? > >Does anyone have a junked SB-220 or other amp with the same sockets from >which you'd be willing to scavenge some non-filament springs? > >Does anyone know of a source for the clips without buying the whole socket? > // Such springs can be bent up from heated austenitic steel piano wire - which is available in hobby shops. No tempering is needed. Temper austenitic steel and it breaks like glass. Trimmed, large size bobby pins also work. cheers, Pete - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From n4zr@contesting.com Wed Oct 10 13:33:11 2001 From: n4zr@contesting.com (Pete Smith) Date: Wed, 10 Oct 2001 08:33:11 -0400 Subject: [AMPS] SB-220 cooling -- another thought In-Reply-To: <200110101221.f9ACLnZ05870@contesting.com> Message-ID: <3.0.5.32.20011010083311.00977220@pop.abs.adelphia.net> At 05:22 AM 10/10/01 -0700, Rich wrote: >// Such springs can be bent up from heated austenitic steel piano wire - >which is available in hobby shops. No tempering is needed. Temper >austenitic steel and it breaks like glass. Trimmed, large size bobby >pins also work. > >cheers, Pete I think we may be talking about different sockets -- the spring clips I was referring to are about 3/8 inch wide, U-shaped, with tongues (at the top of the U) that are bent in slightly and actually press on the contacts. I was asking whether clips made this way might be retemperable... or whether clips that were used on the grid pins, for example, might be swapped into the filament locations. In any case, at the moment my problem is the tube, because when I swap it from one side to the other it still doesn't light up. Anyone know of a net mail-order source for the small butane torch and (particularly) the high-temp silver solder that is apparently needed to attempt a repair? 73, Pete N4ZR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jmbombar@graphnet.fr Wed Oct 10 08:57:59 2001 From: jmbombar@graphnet.fr (Jean-Michel Bombar) Date: Wed, 10 Oct 2001 09:57:59 +0200 Subject: [AMPS] Help building mono band amp References: <005b01c150ed$33af9220$89277ad5@jackie> Message-ID: <012d01c15161$4b0152a0$678ea8c0@jmb2> Hello, I would like to built my first HF amp, I am thinking of a 1Kw mono band amp for the 40M band. Does any of you have any idea of where I could gather informations to start this project? Thanks. Jean-Michel, F5MMX -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 10 14:57:05 2001 From: 2@vc.net (2) Date: Wed, 10 Oct 2001 06:57:05 -0700 Subject: [AMPS] Re: CW/SSB Tune Up Message-ID: <200110101356.f9ADuqZ08525@contesting.com> > >> load, of course. Bird 43 with a 5kW slug was of no use, >> it is way too slow and does not respond to the 50 wpm >> dits. > >Even if the metering system does not indicate peaks, it is generally >good for geting optimum tuning on long pulses. The only >requirement is the rise and fall be short compared to the flat time at >the top. > >There is no magic with speed or duty cycle used, except as it >relates to average dissipation in the elements. // Since a tube's optimal RL is basically E/I, an amplifier needs to be tuned up close to the voltage the anode will see during actual operation. Thus, one reason to use pulse tuning for SSB operation is that there are exceedingly few 1500w output Ham radio amplifiers that have an anode supply which does not have excessive voltage-sag when operated in locked key / A� mode. An example of an amplifier that has little sag in A� is the Henry Radio 3K-A, which has a 2500w anode supply. Unfortunately, the 3K-A has a tendency to intermittently oscillate c. 95MHz. [to measure this frequency, couple a dipmeter to either side of the DC blocking cap. - preferably with the amplifier's power plug pulled] > >> Anyway I found that once the tune and load controls were >> at resonance, they did not seem to need to be tweaked >> as the drive was increased beyond 100 watts or so. > >The load is not resonanted. It sets the anode load impedance. The >plate control is used to set resonance. > >> max C). With 200 watts drive, factory data shows tune dial at 160, >> and the load C is lower, at a dial of 460 or seemingly significantly >> heavier loading of the output. Maybe I should do this all over again >> and just use constant key down for the final tweaking. > >A pulse should be fine with almost any meter, as long as the rise >and fall times are short compared to the on time. The meter does >NOT have to indicate peaks to let you tune the PA properly on a >string of pulses. > // Good points, Mr. Rauch. In a pulse-tuning comparison between an oscilloscope and a garden variety, diode-detector-meter, there was no observable difference in the tank settings. I found that 25 - 30 pulses per second -at 30% duty-cycle- is fast enough to stabilize a meter needle and not cause excessive HV supply sag, yet not fast enough to clip the peaks. >> Well, maybe all of this fiddling is of no point, as I lower >> the drive well down before going to the antenna set up! > >Since most exciters have considerable overshoot, it is always a >good idea to overload the tank somewhat. // In my experiences, using an oscilloscope to observe the RF output waveform, overshoot can be virtually eliminated by running minimal ALC. >You can do that by >opening the load control slightly past the point of maximum output >at full carrier drive. The plate control should always be peaked for >maximum output, unless the manufacturer tells you to do >something else because of unstable feedback or something equally >odd. // Uh-oh. > >Grounded grid amps are really very forgiving, but it is best to load >on the heavy side if you do make an error. >73, Tom W8JI >W8JI@contesting.com - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 10 14:57:07 2001 From: 2@vc.net (2) Date: Wed, 10 Oct 2001 06:57:07 -0700 Subject: [AMPS] Re: CW/SSB Tune Up Message-ID: <200110101356.f9ADurZ08530@contesting.com> > >Hi again, > >And thanks a bunch to the several who have commented >and made specific tune up recommendations! Have >followed them this morning. Rich, I chickened out at >just about 345 watts of drive, hi. // The 3cx3000A7 is rated at 2.5A. If one drives it to less current, one will not get the right E/I ratio for the extant tank. > The grid current was >approaching/bit exceeding 300 mA; Henry manual says >to not exceed 350 mA. // Eimac rates the 3cx3000A7 grid at 225w. Typical cathode-grid potential is c. 190Vrms. With 1000mA of grid-current one would be dissipating c. 190w in the grid. However such grid-current would be quite likely to make for less suds out. Thus, the best policy is to tune for max out with max in. > at All of this into the Bird >load, of course. Bird 43 with a 5kW slug was of no use, >it is way too slow and does not respond to the 50 wpm >dits. // With pulse tuning the 43 works a relarive indicator, which good enough. > >Anyway I found that once the tune and load controls were >at resonance, they did not seem to need to be tweaked >as the drive was increased beyond 100 watts or so. // If I-anode changes and E-anode is constant, RL changes. > >Hope this is correct, ... - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 10 15:27:36 2001 From: 2@vc.net (2) Date: Wed, 10 Oct 2001 07:27:36 -0700 Subject: [AMPS] Help building mono band amp Message-ID: <200110101427.f9AERNZ09338@contesting.com> > >Hello, > >I would like to built my first HF amp, I am thinking of a 1Kw mono band amp >for the 40M band. >Does any of you have any idea of where I could gather informations to start >this project? > // My Web site has some information on building linear amplifiers. > cheerio, Jean-Michel - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 10 15:27:39 2001 From: 2@vc.net (2) Date: Wed, 10 Oct 2001 07:27:39 -0700 Subject: [AMPS] SB-220 cooling -- another thought Message-ID: <200110101427.f9AERQZ09346@contesting.com> > >At 05:22 AM 10/10/01 -0700, Rich wrote: >>// Such springs can be bent up from heated austenitic steel piano wire - >>which is available in hobby shops. No tempering is needed. Temper >>austenitic steel and it breaks like glass. Trimmed, large size bobby >>pins also work. >> >>cheers, Pete > >I think we may be talking about different sockets -- the spring clips I was >referring to are about 3/8 inch wide, U-shaped, with tongues (at the top of >the U) that are bent in slightly and actually press on the contacts. > // Same critters >I was asking whether clips made this way might be retemperable... or >whether clips that were used on the grid pins, for example, might be >swapped into the filament locations. // The grid and fil, contact springs are swapable, but all must squeeze. / As I understand it, mil-spec sockets use tempered springs. Whether or not your springs are temperable is something that only you can find out. If you break one, a modified bobby pin works well - provided you don't tell any macho guys, of course, of course. > >In any case, at the moment my problem is the tube, because when I swap it >from one side to the other it still doesn't light up. Anyone know of a net >mail-order source for the small butane torch and (particularly) the >high-temp silver solder that is apparently needed to attempt a repair? > // Higher temp is not always better because one needs to use Rosin flux - which decomposes above a certain temp. We sell 0.125" d. 430�F Ag-Sn solder for $1.90/ft. It works well with a soldering iron. For resoldering tube pins. it does the job -- provided that the old lead solder is removed first with solder-wick. . cheers, Pete - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w8ik@subich.com Wed Oct 10 18:12:31 2001 From: w8ik@subich.com (Joe Subich, K4IK) Date: Wed, 10 Oct 2001 13:12:31 -0400 Subject: [AMPS] FW: BOUNCE amps@contesting.com : Non-member submission from ["Mike McCarthy, W1NR" ] Message-ID: approved 8877 Message-ID: <3BC47CAF.7F45BFF@eecorp.com> Date: Wed, 10 Oct 2001 12:51:59 -0400 From: "Mike McCarthy, W1NR" X-Mailer: Mozilla 4.76 [en] (Windows NT 5.0; U) X-Accept-Language: en MIME-Version: 1.0 To: amps@contesting.com, qro@qth.net, ETO_Alpha@qth.net Subject: B&W 802 plate choke in an Alpha 77Dx Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Anyone have the specs for a B&W 802 plate choke? Anyone know if it can safely be used as a substitute for a B&W 800 in the Alpha 77Dx? Won't it lower the resonant frequency? If so , to where? Thanks, Mike, W1NR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Wed Oct 10 18:29:39 2001 From: philk5pc@tyler.net (Phil Clements) Date: Wed, 10 Oct 2001 12:29:39 -0500 Subject: [AMPS] FW: BOUNCE amps@contesting.com : Non-member submission from ["Mike McCarthy, W1NR" ] References: Message-ID: <000d01c151b1$267a6020$b6094c42@phil> The 802 is physically the same as an 800, just a few more turns. If you don't have a dip meter to find the resonances with the choke mounted in place in the amp, You can make an 800 out of an 802 just by removing turns. (((73))) Phil, K5PC > Anyone have the specs for a B&W 802 plate choke? Anyone know if it can > safely be used as a substitute for a B&W 800 in the Alpha 77Dx? Won't > it lower the resonant frequency? If so , to where? > > Thanks, > Mike, W1NR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k7dd@qwest.net Wed Oct 10 18:36:50 2001 From: k7dd@qwest.net (Mike Baker) Date: Wed, 10 Oct 2001 10:36:50 -0700 Subject: [AMPS] Help building mono band amp References: <005b01c150ed$33af9220$89277ad5@jackie> <012d01c15161$4b0152a0$678ea8c0@jmb2> Message-ID: <004001c151b2$256fd880$ed850d82@speedchoice.com> Hello, Get an ARRL handbook from say, 1965. For several years there was an article on building monoband KW amps using a pair of 813's. I used these articles as the basis for my very first amp in 1969. 813's are still available via various sources including the internet and are quite inexpensive. I scrounged around for a year or so on e-bay and made a deal with a fellow to buy 9 tubes and 4 sockets for $80 including the shipping. 7 tubes were carbon plates (the best ones IMHO) and 2 were the metal plates. One broke in shipping (not carbon,no loss). For any band up to 20 meters they kick butt and love high voltage. The book specs say 2500VDC max for the plates but up to 3500VDC is commonly used in GG linear service. 4 tubes will give you a comfortable KW out at 2.5 to 3KV. For up to say 750 out you could use two tubes and have an easier time finding the filament transformer. (10VAC at 10Amps for two tubes) Used a surplus 150pf cap for my tuning on 40M and made the coil out of copper tubing. The power xfmr was a surplus unit that ran 900VAC at 1A as a voltage doubler. Total cost back then (1969) was maybe $30 but you could still build one today for less than a $100 with a little patience and scrounging. The best part of building is you get to test and refine a bunch of talents. Sheet metal fabrication, wiring or harness making, parts recognition and purchase, electronic design, metal finishing/painting, etc. just to name a few. A few caveat come to mind. I mention these to anyone who is contemplating building their first amp. 1. HIGH VOLTAGE is not just a sticker on the side of a cabinet. It is a seductive lover that will KILL you and bring you to room temperature if not respected and the rules of working around it obeyed to the letter. You seldom get a second chance let alone a third to violate the rules. I have been blessed with having survived lethal shocks twice and figure that a third is not likely so be aware. DO NOT put your hands inside a cabinet that has High Voltage (anything above 24Volts AC or DC) present. The AC power mains kill more people every year than any other type of electrocution. Work with one hand in your pocket. NOT leaning on a grounded metal cabinet or desk. Always disconnect the mains power and flag or wrap up the plug end so it isn't accidentally reconnected by someone else. (The old story about two guys working on a transmitter together and as one guy has his hands inside the cabinet, the other finds the plug pulled from the mains and plugs it back in without thinking, saying something like, "OH, I found the problem, it isn't plugged in; try it NOW!" Room temperature. Use a "shorting" stick or discharge stick. In days of old a large metal loop shaped like a large fish hook with a wooden handle and a piece of braid with and alligator clip on one end clipped to ground. Today I would modify that to be a probe type of stick with a non-conductive handle hooked to a long string of 2 watt metal film resistors with a total value of about 100K Ohms or so. Use it to check the discharged state of the HV caps before you start working on the amp. Use a shorting clip across the HV to GND and remove it when you are done. IF, IF someone accidentally turns on the power while you are inside the cabinet, it will/should blow the FUSE or Circuit Breakers and keep you from being a dead fish. NEVER, NEVER build an amp without proper fusing of the mains. NEVER, NEVER bridge the safety devices (fuses or breakers). They have a purpose. NEVER, NEVER work on a project involving High Voltage while you are exhausted or overly tired. Falling asleep into your work can be deadly. Too tired and you do stupid things you might never recover from. NEVER, NEVER work on a project involving High Voltage if you are intoxicated. Same result as the previous warning. Save the 807's for the celebration of a successful days work. All of these previous warnings are old hat and inevitable truths to staying alive while working around High Voltage as I am sure most would agree. Let me add a couple of my own. Realizing that the Human nature of things is to do something as long as you can so long as it doesn't hurt you, all of us at some time or another have violated one of the rules listed above. Some of us have survived the experience. Some of us had Help surviving the experience. If you don't know CPR go and learn it. Once you do you will posses a skill that you may never have to use (hopefully). But the alternative to not knowing it may cost someone their life and it just might be someone you love. My personal feeling is that it should be taught in junior high school and a requirement for a drivers license. It could greatly reduce the risk of death to thousands. Remember, electrocution causes the heart to stop and CPR applied immediately after the victim is clear of the danger can make the difference in being back to normal or a "gomer". If you must work on a piece of equipment that involves high voltage do NOT do it alone. Be sure someone knows where you are and what you are doing. Have a buddy give you a hand. (It can be more fun doing these things as a "buddy" project.) There is nothing more unnerving than to have your wife come home and find you "well done" and at room temperature out in your garage or in your shack. It ruins their day and yours! OK, I know this all seems like I am describing the obvious, but it is worth repeating. It is sort of like meeting a beautiful woman in a club. YOU ONLY GET ONE CHANCE TO MAKE A GOOD FIRST IMPRESSION! You will seldom get a second chance. Good luck with your amp project. READ, READ, READ, and if you still have questions, at least you know where to ask. In spite of all of the banter and sniping at each other on occasion, this is still one of the best resources for information on AMPS. You could never say this group isn't passionate about what they are doing. Again, good luck. Mike Baker K7DD k7dd@qwest.net ----- Original Message ----- From: "Jean-Michel Bombar" To: Sent: Wednesday, October 10, 2001 12:57 AM Subject: [AMPS] Help building mono band amp > > Hello, > > I would like to built my first HF amp, I am thinking of a 1Kw mono band amp > for the 40M band. > Does any of you have any idea of where I could gather informations to start > this project? > > Thanks. > > Jean-Michel, F5MMX > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From bjk@ihug.co.nz Wed Oct 10 22:15:33 2001 From: bjk@ihug.co.nz (Barry Kirkwood) Date: Thu, 11 Oct 2001 10:15:33 +1300 Subject: [AMPS] Help building mono band amp References: <005b01c150ed$33af9220$89277ad5@jackie> <012d01c15161$4b0152a0$678ea8c0@jmb2> <004001c151b2$256fd880$ed850d82@speedchoice.com> Message-ID: <010b01c151d0$b3ab9b20$78d0adcb@ihug.co.nz> Yep, similar 2x813 amp in older "Radio Handbook" by Bill Orr. A proven performer. 73 es gl. end Barry Kirkwood PhD ZL1DD Signal Hill Homestay 66 Cory Road Palm Beach Waiheke Island 1240 NEW ZEALAND www.waiheke.co.nz/signal.htm ----- Original Message ----- From: Mike Baker To: AMPS REFLECTOR ; Jean-Michel Bombar Sent: Thursday, 11 October, 2001 6:36 AM Subject: Re: [AMPS] Help building mono band amp > > Hello, > Get an ARRL handbook from say, 1965. For several years there was an > article on building monoband KW amps using a pair of 813's. I used these > articles as the basis for my very first amp in 1969. 813's are still > available via various sources including the internet and are quite > inexpensive. I scrounged around for a year or so on e-bay and made a deal > with a fellow to buy 9 tubes and 4 sockets for $80 including the shipping. > 7 tubes were carbon plates (the best ones IMHO) and 2 were the metal plates. > One broke in shipping (not carbon,no loss). For any band up to 20 meters > they kick butt and love high voltage. The book specs say 2500VDC max for > the plates but up to 3500VDC is commonly used in GG linear service. 4 tubes > will give you a comfortable KW out at 2.5 to 3KV. For up to say 750 out you > could use two tubes and have an easier time finding the filament > transformer. (10VAC at 10Amps for two tubes) Used a surplus 150pf cap for > my tuning on 40M and made the coil out of copper tubing. The power xfmr was > a surplus unit that ran 900VAC at 1A as a voltage doubler. > Total cost back then (1969) was maybe $30 but you could still build one > today for less than a $100 with a little patience and scrounging. The best > part of building is you get to test and refine a bunch of talents. Sheet > metal fabrication, wiring or harness making, parts recognition and purchase, > electronic design, metal finishing/painting, etc. just to name a few. > A few caveat come to mind. I mention these to anyone who is > contemplating building their first amp. > 1. HIGH VOLTAGE is not just a sticker on the side of a cabinet. It > is a seductive lover that will KILL you and bring you to room temperature if > not respected and the rules of working around it obeyed to the letter. You > seldom get a second chance let alone a third to violate the rules. I have > been blessed with having survived lethal shocks twice and figure that a > third is not likely so be aware. > DO NOT put your hands inside a cabinet that has High Voltage (anything > above 24Volts AC or DC) present. The AC power mains kill more people every > year than any other type of electrocution. > Work with one hand in your pocket. NOT leaning on a grounded metal > cabinet or desk. > Always disconnect the mains power and flag or wrap up the plug end so it > isn't accidentally reconnected by someone else. (The old story about two > guys working on a transmitter together and as one guy has his hands inside > the cabinet, the other finds the plug pulled from the mains and plugs it > back in without thinking, saying something like, "OH, I found the problem, > it isn't plugged in; try it NOW!" Room temperature. > Use a "shorting" stick or discharge stick. In days of old a large metal > loop shaped like a large fish hook with a wooden handle and a piece of braid > with and alligator clip on one end clipped to ground. Today I would modify > that to be a probe type of stick with a non-conductive handle hooked to a > long string of 2 watt metal film resistors with a total value of about 100K > Ohms or so. Use it to check the discharged state of the HV caps before you > start working on the amp. > Use a shorting clip across the HV to GND and remove it when you are > done. IF, IF someone accidentally turns on the power while you are inside > the cabinet, it will/should blow the FUSE or Circuit Breakers and keep you > from being a dead fish. > NEVER, NEVER build an amp without proper fusing of the mains. > NEVER, NEVER bridge the safety devices (fuses or breakers). They have a > purpose. > NEVER, NEVER work on a project involving High Voltage while you are > exhausted or overly tired. Falling asleep into your work can be deadly. > Too tired and you do stupid things you might never recover from. > NEVER, NEVER work on a project involving High Voltage if you are > intoxicated. Same result as the previous warning. Save the 807's for the > celebration of a successful days work. > All of these previous warnings are old hat and inevitable truths to > staying alive while working around High Voltage as I am sure most would > agree. Let me add a couple of my own. > Realizing that the Human nature of things is to do something as long as > you can so long as it doesn't hurt you, all of us at some time or another > have violated one of the rules listed above. Some of us have survived the > experience. Some of us had Help surviving the experience. > If you don't know CPR go and learn it. Once you do you will posses a > skill that you may never have to use (hopefully). But the alternative to > not knowing it may cost someone their life and it just might be someone you > love. My personal feeling is that it should be taught in junior high school > and a requirement for a drivers license. It could greatly reduce the risk of > death to thousands. Remember, electrocution causes the heart to stop and > CPR applied immediately after the victim is clear of the danger can make the > difference in being back to normal or a "gomer". > If you must work on a piece of equipment that involves high voltage do > NOT do it alone. Be sure someone knows where you are and what you are > doing. Have a buddy give you a hand. (It can be more fun doing these things > as a "buddy" project.) There is nothing more unnerving than to have your > wife come home and find you "well done" and at room temperature out in your > garage or in your shack. It ruins their day and yours! > > OK, I know this all seems like I am describing the obvious, but it is > worth repeating. > It is sort of like meeting a beautiful woman in a club. YOU ONLY GET > ONE CHANCE TO MAKE A GOOD FIRST IMPRESSION! You will seldom get a second > chance. > > Good luck with your amp project. READ, READ, READ, and if you still > have questions, at least you know where to ask. In spite of all of the > banter and sniping at each other on occasion, this is still one of the best > resources for information on AMPS. You could never say this group isn't > passionate about what they are doing. > Again, good luck. > Mike Baker K7DD > k7dd@qwest.net > ----- Original Message ----- > From: "Jean-Michel Bombar" > To: > Sent: Wednesday, October 10, 2001 12:57 AM > Subject: [AMPS] Help building mono band amp > > > > > > Hello, > > > > I would like to built my first HF amp, I am thinking of a 1Kw mono band > amp > > for the 40M band. > > Does any of you have any idea of where I could gather informations to > start > > this project? > > > > Thanks. > > > > Jean-Michel, F5MMX > > > > > > -- > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > Submissions: amps@contesting.com > > Administrative requests: amps-REQUEST@contesting.com > > Problems: owner-amps@contesting.com > > > > > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From n4zr@contesting.com Wed Oct 10 22:15:24 2001 From: n4zr@contesting.com (Pete Smith) Date: Wed, 10 Oct 2001 17:15:24 -0400 Subject: [AMPS] Filament resistance and power output Message-ID: <3.0.5.32.20011010171524.008cdd20@pop.abs.adelphia.net> I resoldered the filament pins on the ailing 3-500Z, and then put it in the opposite socket, thinking that the spring tension might be better there. I also rebent the spring clips on the original socket and cleaned and treated the filament pins with Caig ProGold GxL, which is rated for use up to 400C. When I fired the amp up, with the originally OK tube in the not-OK socket, I was surprised to see that tube's filament was noticeably brighter than the other one. So I repeated the ProGold treatment on the other socket, and the filament brightness equalized at the higher level. Then I turned on the amp, and was startled to see that my output had increased 100 watts, with the same drive and other conditions. I don't quite understand what's going on here. From time to time I've heard amazing things about Caig's products, such as Deoxit, but this was a new one on me. What's the physical explanation, if any? 73, Pete N4ZR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From bjk@ihug.co.nz Wed Oct 10 22:22:32 2001 From: bjk@ihug.co.nz (Barry Kirkwood) Date: Thu, 11 Oct 2001 10:22:32 +1300 Subject: [AMPS] Beginner's amp project Message-ID: <011d01c151d1$ad223740$78d0adcb@ihug.co.nz> More on 813 gg: There is a very good design and description in RSGB Radio Communication Handbook 5th Edition Vol 1. 1976 pp 6.122 et seq. Some libraries may have copies in the basement. 73 end Barry Kirkwood PhD ZL1DD Signal Hill Homestay 66 Cory Road Palm Beach Waiheke Island 1240 NEW ZEALAND www.waiheke.co.nz/signal.htm -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From paulc@mediaone.net Wed Oct 10 23:22:05 2001 From: paulc@mediaone.net (Paul Christensen) Date: Wed, 10 Oct 2001 18:22:05 -0400 Subject: [AMPS] Re: [ETO_Alpha] B&W 802 plate choke in an Alpha 77Dx References: <3BC47CAF.7F45BFF@eecorp.com> Message-ID: <005101c151d9$fe933d60$7a01a8c0@se.mediaone.net> > Anyone have the specs for a B&W 802 plate choke? Anyone know if it can > safely be used as a substitute for a B&W 800 in the Alpha 77Dx? Yes. In fact, the added inductance will in the #802 will allow for 24 MHz operation with the 77DX/77Dx/77/PA70-V. Dick Byrd, N4UQ, offers an exchange program where he sends you an #802 equivalent replacement in exchange for your old 800. I don't recall the cost but it was more than reasonable. The ceramic core is essentially the same between the 800 and 802. Dick simply strips the magnet wire and rewinds it with ~ 1.5 inches of additional wire. He also increases the wire gauge size which allows for safer operation in the 77Sx. I believe the following link will take you to Dick's sire where you can obtain additional information. http://www.jps.net/n4uq/ -Paul, W9AC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter V. Ritter" This is a multi-part message in MIME format. ------=_NextPart_000_00AE_01C151A0.1EE18D40 Content-Type: multipart/alternative; boundary="----=_NextPart_001_00AF_01C151A0.1EE18D40" ------=_NextPart_001_00AF_01C151A0.1EE18D40 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable Greetings from AC6KD ... =20 Does anyone have the 10 meter mod for the Kenwood = TL-922A amplifier ? It would be much appreciated ! Pete = r.peter@verizon.net ------=_NextPart_001_00AF_01C151A0.1EE18D40 Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable
     Greetings from AC6KD ...



           &n= bsp;     =20 Does anyone have the 10 meter mod for the Kenwood TL-922A amplifier = ? It=20 would be much appreciated !

           &n= bsp;           &nb= sp;           &nbs= p;            = ; =20 Pete          r.peter@verizon.net
<= /HTML> ------=_NextPart_001_00AF_01C151A0.1EE18D40-- ------=_NextPart_000_00AE_01C151A0.1EE18D40 Content-Type: image/gif; name="WhiteLinen.gif" Content-Transfer-Encoding: base64 Content-ID: <00ad01c151da$cb406540$feca2b04@vz.dsl.genuity.net> R0lGODdhPAA8AP8AMdzc3OTk5Ozs7PT09P///wAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACwAAAAAPAA8AAAI/wADEBAw oOBAAgMIEhAIYGHBhwMJJiQw8GFCgwoFTiwYYEBFigcFLAT5UCRFjw07XqQYQKJGkR4NejQJk6MA hRILEgwQoOFNkzMnqjQYUeRNhDE75sQIU+LRiUh/IkR60mLBhlM/RtRJEatCj1utwuwY8eRNjBwx Uq16dinSmUAHtKRKlqvZimBnspwaU6bYh3MRShVsNGZNtH9bMiXq1+zZgyAFBK6aFuJBvWDfRl6Z UHJnihJBRm0LurNJwRc3jgzqcCNEmJoBEJwt+Wxmkm8NZ9apUPDak6XBPiYKmnLY2aodFq+o8nLq kjzNEufqGWLjyFEFbt1eczbJydSLmv9UyhF4cKvWY8pG2JAx7pLu+y70HhL2TJ6h2b6vyfdidJmr rSSVXZS1BJRoeCE0V0zG8TWQQDit5BuDqGUWl3RyldSfTip9NZ1WcDVFk2OmIahZX+WJxhSETh11 E4R5RWaUcjn9VB518vF2n3DayXTURy4qNpVGQlZkI41s4URViNY5lxN7qkUoH0kWOYSVhcKJZGBC zQnUY2kHKoebbz/mVthJLwmnVXET2cYlkEP1FlqNmhn5nJrCAZYglel9CN9SHmkUo04+8uWWTGRV aBmaXF50YFot4SemfWMBdRqDEbJ5FotT7kglcKxJ9uB3SYVWJVuACQCAYTJa+OOLw93/FlxVeKFF 65hZlXUXVKoSJ+psill6JFNFwShUaxDJNtecWkbF0lcq2pcncEcZmyKb2G2W13i6gZZofk1p55SP fv3UVKDozpqhXxT+KNdjoJ0JIKEqNpfuuZ1h6ZtorwIJakbpGTgiURndJeOnpsHnYFtQYdaYdoTJ J+pB5ElGVl3wGWQgakbV1F6MzEGlGU8QUmWbUkOh2LFTUVkGl64yAfDtdADWKlZxsDlIYbD7yhWx joJtSTFWOmvm3XNyqhzogmpmlZdGE352mpzx5pdbg6vGS5htLgX1JK1pzUegYW7a5vRnTrM81aOH GpfXu21KDGiVWXrt4gDrJWkrimrZ/8cSg47qBXbci84bEn5hHyhsnEviXN1ub0F73EeGA7vTbXbZ mFPW5znbl735vW33kjUGOvBhej2JXKFD5cZY62qtxe6cvEF2eZtraiy1XEVW+GDHoOI8IW0+X1bd nv1l1ayT2BHK35kbPvr23C9bRJBseV4qcmcdhsVYvhSmVhqotq6NG+3AuyatteRmp1tQmM6H6o27 dcuZyJ77/D2rYL7r71MtIlSh7PImDQ1KYIppGEQuZjvAmedv89mYlGhGOrpdikQWtFeGnoIgQQXn JjKDTP0SdDcRrY4ogVHTi1SSMsyYrC4e3AtgEGOVsNipdmiz2Zmgtiyy1QlFjZOPT1pu9Smo0U0p lzlYATkTPNdpiTUk6Q0Bhkim8fXlUlZLkKOSxivXrAtuyDFZ5AKXIfNAi0Vrg1yPiHeYaDmPfPTq zRcdgyz07E9bgXIaXhBnMHExLSAAAAAAAAAAOw== ------=_NextPart_000_00AE_01C151A0.1EE18D40-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k7rdx@earthlink.net Wed Oct 10 22:42:41 2001 From: k7rdx@earthlink.net (K7RDX) Date: Wed, 10 Oct 2001 14:42:41 -0700 Subject: [AMPS] Help building mono band amp References: <005b01c150ed$33af9220$89277ad5@jackie> <012d01c15161$4b0152a0$678ea8c0@jmb2> <004001c151b2$256fd880$ed850d82@speedchoice.com> Message-ID: <001301c151d4$82905c20$b25e1b3f@jim> Really good advice, Mike... you usually don`t get a second chance with hv equipment.This is certainly something first time amp constructors (and seasoned vets as well!) should put first on the safety list! 73 to all, Jim, K7RDX ----- Original Message ----- From: Mike Baker To: AMPS REFLECTOR ; Jean-Michel Bombar Sent: Wednesday, October 10, 2001 10:36 AM Subject: Re: [AMPS] Help building mono band amp > > Hello, > Get an ARRL handbook from say, 1965. For several years there was an > article on building monoband KW amps using a pair of 813's. I used these > articles as the basis for my very first amp in 1969. 813's are still > available via various sources including the internet and are quite > inexpensive. I scrounged around for a year or so on e-bay and made a deal > with a fellow to buy 9 tubes and 4 sockets for $80 including the shipping. > 7 tubes were carbon plates (the best ones IMHO) and 2 were the metal plates. > One broke in shipping (not carbon,no loss). For any band up to 20 meters > they kick butt and love high voltage. The book specs say 2500VDC max for > the plates but up to 3500VDC is commonly used in GG linear service. 4 tubes > will give you a comfortable KW out at 2.5 to 3KV. For up to say 750 out you > could use two tubes and have an easier time finding the filament > transformer. (10VAC at 10Amps for two tubes) Used a surplus 150pf cap for > my tuning on 40M and made the coil out of copper tubing. The power xfmr was > a surplus unit that ran 900VAC at 1A as a voltage doubler. > Total cost back then (1969) was maybe $30 but you could still build one > today for less than a $100 with a little patience and scrounging. The best > part of building is you get to test and refine a bunch of talents. Sheet > metal fabrication, wiring or harness making, parts recognition and purchase, > electronic design, metal finishing/painting, etc. just to name a few. > A few caveat come to mind. I mention these to anyone who is > contemplating building their first amp. > 1. HIGH VOLTAGE is not just a sticker on the side of a cabinet. It > is a seductive lover that will KILL you and bring you to room temperature if > not respected and the rules of working around it obeyed to the letter. You > seldom get a second chance let alone a third to violate the rules. I have > been blessed with having survived lethal shocks twice and figure that a > third is not likely so be aware. > DO NOT put your hands inside a cabinet that has High Voltage (anything > above 24Volts AC or DC) present. The AC power mains kill more people every > year than any other type of electrocution. > Work with one hand in your pocket. NOT leaning on a grounded metal > cabinet or desk. > Always disconnect the mains power and flag or wrap up the plug end so it > isn't accidentally reconnected by someone else. (The old story about two > guys working on a transmitter together and as one guy has his hands inside > the cabinet, the other finds the plug pulled from the mains and plugs it > back in without thinking, saying something like, "OH, I found the problem, > it isn't plugged in; try it NOW!" Room temperature. > Use a "shorting" stick or discharge stick. In days of old a large metal > loop shaped like a large fish hook with a wooden handle and a piece of braid > with and alligator clip on one end clipped to ground. Today I would modify > that to be a probe type of stick with a non-conductive handle hooked to a > long string of 2 watt metal film resistors with a total value of about 100K > Ohms or so. Use it to check the discharged state of the HV caps before you > start working on the amp. > Use a shorting clip across the HV to GND and remove it when you are > done. IF, IF someone accidentally turns on the power while you are inside > the cabinet, it will/should blow the FUSE or Circuit Breakers and keep you > from being a dead fish. > NEVER, NEVER build an amp without proper fusing of the mains. > NEVER, NEVER bridge the safety devices (fuses or breakers). They have a > purpose. > NEVER, NEVER work on a project involving High Voltage while you are > exhausted or overly tired. Falling asleep into your work can be deadly. > Too tired and you do stupid things you might never recover from. > NEVER, NEVER work on a project involving High Voltage if you are > intoxicated. Same result as the previous warning. Save the 807's for the > celebration of a successful days work. > All of these previous warnings are old hat and inevitable truths to > staying alive while working around High Voltage as I am sure most would > agree. Let me add a couple of my own. > Realizing that the Human nature of things is to do something as long as > you can so long as it doesn't hurt you, all of us at some time or another > have violated one of the rules listed above. Some of us have survived the > experience. Some of us had Help surviving the experience. > If you don't know CPR go and learn it. Once you do you will posses a > skill that you may never have to use (hopefully). But the alternative to > not knowing it may cost someone their life and it just might be someone you > love. My personal feeling is that it should be taught in junior high school > and a requirement for a drivers license. It could greatly reduce the risk of > death to thousands. Remember, electrocution causes the heart to stop and > CPR applied immediately after the victim is clear of the danger can make the > difference in being back to normal or a "gomer". > If you must work on a piece of equipment that involves high voltage do > NOT do it alone. Be sure someone knows where you are and what you are > doing. Have a buddy give you a hand. (It can be more fun doing these things > as a "buddy" project.) There is nothing more unnerving than to have your > wife come home and find you "well done" and at room temperature out in your > garage or in your shack. It ruins their day and yours! > > OK, I know this all seems like I am describing the obvious, but it is > worth repeating. > It is sort of like meeting a beautiful woman in a club. YOU ONLY GET > ONE CHANCE TO MAKE A GOOD FIRST IMPRESSION! You will seldom get a second > chance. > > Good luck with your amp project. READ, READ, READ, and if you still > have questions, at least you know where to ask. In spite of all of the > banter and sniping at each other on occasion, this is still one of the best > resources for information on AMPS. You could never say this group isn't > passionate about what they are doing. > Again, good luck. > Mike Baker K7DD > k7dd@qwest.net > ----- Original Message ----- > From: "Jean-Michel Bombar" > To: > Sent: Wednesday, October 10, 2001 12:57 AM > Subject: [AMPS] Help building mono band amp > > > > > > Hello, > > > > I would like to built my first HF amp, I am thinking of a 1Kw mono band > amp > > for the 40M band. > > Does any of you have any idea of where I could gather informations to > start > > this project? > > > > Thanks. > > > > Jean-Michel, F5MMX > > > > > > -- > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > Submissions: amps@contesting.com > > Administrative requests: amps-REQUEST@contesting.com > > Problems: owner-amps@contesting.com > > > > > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter V. Ritter" This is a multi-part message in MIME format. ------=_NextPart_000_0126_01C151A8.4EA55C20 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Greetings from AC6KD ... =20 Does anyone have the 10 meter mod for the Kenwood = TL-922A amplifier ? It would be much appreciated ! =20 Pete ------=_NextPart_000_0126_01C151A8.4EA55C20 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
    =20 Greetings from AC6KD ...
    =20 =
           &nb= sp;     =20 Does anyone have the 10 meter mod for the Kenwood TL-922A
amplifier = ? =20 It would be much appreciated !
=20 =
           &nb= sp;           &nbs= p;            = ;            = =20 Pete
------=_NextPart_000_0126_01C151A8.4EA55C20-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Mike" Message-ID: <013101c151ec$aa796a20$6401a8c0@neptune> Hi Pete, Filament current on the 3-500Z is around 15 amps per tube. Fourty millohms (.04 ohms) of contact resistance, for instance, is enough to drop the filament voltage by 0.6 volts, or 12% of the nominal filament voltage (Vf nom= 5.0 Volts). I don't know where the cathode emission of the 3-500Z really starts to fall off, but one can easily see that it doesn't take much extra contact resistance in series with the tube filament to have a significant effect on the filament voltage and ultimately the electron emission. Since the filaments got noticeably brighter after the contact treatment, I suspect that improved cathode emission was the mechanism responsible for the increased output power. 73 de Mike, W4EF....... ---- Original Message ----- From: "Pete Smith" To: Sent: Wednesday, October 10, 2001 2:15 PM Subject: [AMPS] Filament resistance and power output > > I resoldered the filament pins on the ailing 3-500Z, and then put it in the > opposite socket, thinking that the spring tension might be better there. I > also rebent the spring clips on the original socket and cleaned and treated > the filament pins with Caig ProGold GxL, which is rated for use up to 400C. > > When I fired the amp up, with the originally OK tube in the not-OK socket, > I was surprised to see that tube's filament was noticeably brighter than > the other one. So I repeated the ProGold treatment on the other socket, > and the filament brightness equalized at the higher level. Then I turned > on the amp, and was startled to see that my output had increased 100 watts, > with the same drive and other conditions. > > I don't quite understand what's going on here. From time to time I've > heard amazing things about Caig's products, such as Deoxit, but this was a > new one on me. What's the physical explanation, if any? > > 73, Pete N4ZR > > > > > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Thu Oct 11 03:19:26 2001 From: 2@vc.net (2) Date: Wed, 10 Oct 2001 19:19:26 -0700 Subject: [AMPS] Kenwood TL-922A Message-ID: <200110110219.f9B2JCZ24676@contesting.com> > Greetings from AC6KD ... > > Does anyone have the 10 meter mod for the Kenwood >TL-922A amplifier ? It would be much appreciated ! > // It's on my Website, Pete. - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Thu Oct 11 04:31:23 2001 From: 2@vc.net (2) Date: Wed, 10 Oct 2001 20:31:23 -0700 Subject: [AMPS] Filament resistance and power output Message-ID: <200110110331.f9B3V8Z25809@contesting.com> > >Hi Pete, > >Filament current on the 3-500Z is around 15 amps per tube. Fourty millohms >(.04 ohms) >of contact resistance, for instance, is enough to drop the filament >voltage by 0.6 volts, >or 12% of the nominal filament voltage (Vf nom= 5.0 Volts). I don't know >where the cathode >emission of the 3-500Z really starts to fall off, but one can easily see >that it doesn't take >much extra contact resistance in series with the tube filament to have a >significant effect >on the filament voltage and ultimately the electron emission. Since the >filaments got noticeably >brighter after the contact treatment, I suspect that improved cathode >emission was the >mechanism responsible for the increased output power. > What is the voltage between pin 5 and the socket contact #5? What is the voltage between pin 1 and pin 5? tnx, Mike - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ko4nrbs@yahoo.com Thu Oct 11 04:45:08 2001 From: ko4nrbs@yahoo.com (Bill Smith) Date: Wed, 10 Oct 2001 20:45:08 -0700 (PDT) Subject: [AMPS] SB-221 High Voltage Transformer Message-ID: <20011011034508.72260.qmail@web20508.mail.yahoo.com> Posting for a friend. His name and email is as follows: Joseph Ingram email: mssybil@bellsouth.net Son-in-law lost high voltage xfmr in his sb221. Heard about any sources which are reasonable? Dahl wants enough to make it worthwhile to find another used unit. 73, Bill ===== Bill Smith KO4NR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From gclute@home.com Thu Oct 11 05:37:27 2001 From: gclute@home.com (Geo Clute W7LFD) Date: Wed, 10 Oct 2001 21:37:27 -0700 Subject: [AMPS] Help building mono band amp In-Reply-To: <004001c151b2$256fd880$ed850d82@speedchoice.com> Message-ID: <000001c1520e$6e293a60$6401a8c0@bllvu1.wa.com> >-----Original Message----- >From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On >Behalf Of Mike Baker >Sent: Wednesday, October 10, 2001 10:37 AM >To: AMPS REFLECTOR; Jean-Michel Bombar >Subject: Re: [AMPS] Help building mono band amp For any band up to 20 meters they kick butt and love high voltage. The 813's typical operation is to 30 MHz. I ran a pair on 10 meters with 3350VDC on the plates. Drove them with a Swan 500cx until the carbon plates many red hues...Couldn't burn them out. 1983 "The Radio Amateur's Handbook" Freq.: 30 Mc. Plate V. 2500 Plate MA 125 Screen ma. 20 fil 10v 5A Screen Volts 800 Cin PF 16.3 C gp PF .025 C out PF 14 Typical output AB2 two tubes is 650 W Regards, Geo W7LFD -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Thu Oct 11 08:04:14 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Thu, 11 Oct 2001 08:04:14 +0100 Subject: [AMPS] Tuned Input, what me worry Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A962@excalibur.swindon.msl.mitel.com> Rich asked: >// As I recall, the 5-band Collins 30L-1 recommended a certain length of >input coax. Does anyone have info on this? The 30S1 with the 4CX1000 certainly did, and I'm pretty sure the 30L1 did in its amateur form, too. But the 30L1 was used for the whole HF range (mainly by the US military - who said COTS is a new idea?) and so I believe the principle was abandoned. The special length was to get the electrical length to a multiple of 180 degrees in each amateur band to minimise phase distortion effects from the varying input load that the gg linear represented. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jtml@lanl.gov Thu Oct 11 16:41:08 2001 From: jtml@lanl.gov (John T. M. Lyles) Date: Thu, 11 Oct 2001 09:41:08 -0600 Subject: [AMPS] HV warning Message-ID: K7DD, Mike Baker, has printed a very detailed and wise treastise on the hazards of high voltage. Everything he said reminds me of various accidents and scenarios for accidents which I can remember. I have never felt the jab of derious DC HV supplies, but have seen others do it. Plenty of AC mains shocks as a kid, and lots of HV from tesla coiling and spark plugs, induction coils, etc. But everytime I go into a many kilojoule bank of capacitors that had been charged up to 80 kV minutes before entry (and properly discharged), I consider it like walking in a mine field. Our procedures at work are sometimes dozens of pages long, with annual retraining required to be qualified to work. Also, we have annual CPR retraining as a job requirement. All of this is now necessary as the current crop of electronics technicians come into this field with backgrounds working at less than 20 volts. At home, when I was rebuilding an SB220 ~7 years ago, I did find it awfully easy to expose myself to hazardous voltage. Ham gear is so easy to have interlocks cheated (what interlocks?). And it was late at night - I was alone. When you work a full day and then do your home projects into the wee hours, this is a possibility. I had to remember the same 'fear of god' (sorry I am not extremely religious, just an expression) feeling that I get at work when I walk into a capacitor room the size of my own living room. But on the bench at home, it is so easy to think "how can such a small chassis kill me?". When you short out a charged HV capacitor with your stick it becomes very obvious! Broadcast gear (tube transmitters mainly) is similarly very dangerous, esp the older Gates, Collins, etc, where the door interlock button could be pulled and locked to operate with the rig open. Add to the hazard the fact that most transmitters get repaired after midnight when everyone is asleep (except the engineer on duty) and that most broadcasters are so cheap that they cannot afford two workers doing the task. I remember neutralizing the BC-1G alone, one hand behind my back, the 833s glowing at eye level. HV was off, as prescribed, but nothing would prevent a relay or short from accidentally closing. Worse than this was the SCR controlled rigs, like the Collins 2.5 kW FM transmitter, which would ramp up without having the klunk of a mains contactor. Easy to accidentally power it up from a simple 24 volt contact closure at the remote panel (did I remember to switch to local before working on it? Oh its OK, there is no one else in the building at this hour. RIGHT) Once I stuck my grounding stick on the terminals of a 20 uF 5 kV oil capacitor before reaching in to a rig, and it nearly blew the end off, as the bleeder had failed open. This was at least 5 minutes after power down. Yikes, these things do happen. That could have easily been my finger/arm. 73 to all, and please be careful. John K5PRO > 1. HIGH VOLTAGE is not just a sticker on the side of a cabinet. It >is a seductive lover that will KILL you and bring you to room temperature if >not respected and the rules of working around it obeyed to the letter. You >seldom get a second chance let alone a third to violate the rules. I have >been blessed with having survived lethal shocks twice and figure that a >third is not likely so be aware. ..... -- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ToddRoberts2001@aol.com Thu Oct 11 20:44:10 2001 From: ToddRoberts2001@aol.com (ToddRoberts2001@aol.com) Date: Thu, 11 Oct 2001 15:44:10 EDT Subject: [AMPS] HV warning Message-ID: <7b.1c754869.28f7508a@aol.com> John , thanks for the reminders about the potential hazards of working around high voltage. Another rule of thumb I always follow : NEVER , EVER work around high voltage after you have had even ONE beer. 73 Todd Roberts WD4NGG . -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 12 00:42:31 2001 From: 2@vc.net (2) Date: Thu, 11 Oct 2001 16:42:31 -0700 Subject: [AMPS] HV warning Message-ID: <200110112342.f9BNgEZ14452@contesting.com> > >John , thanks for the reminders about the potential hazards of working >around >high voltage. Another rule of thumb I always follow : NEVER , EVER work >around high voltage after you have had even ONE beer. 73 Todd Roberts >WD4NGG . > � Amen to that. For many OT beer drinkers, One beer is not enough to control the shakes. To be safe, a minimum of two 811s or four 807s should be imbibed. cheers - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w5set@alltel.net Fri Oct 12 04:01:39 2001 From: w5set@alltel.net (steve) Date: Thu, 11 Oct 2001 22:01:39 -0500 Subject: [AMPS] Help building mono band amp Message-ID: <014001c152ca$378ddd00$078227a2@steve> the 813 amp idea is sound----working anywhere with one hand is just like working with several of the "fermented products that i won't mention before starting your project"---damn stupid advise!! please use BOTH hands WITH BRAIN engaged FIRST!!!! I have been a construction electrician for years and years and have heard this crap as long---- and have fought the spreading of this really stupid advise as long too!! i really suppose all you electronic sages solder stuff together with one hand or route wiring with one hand---- if i ever catch an electrician trying to land a wire in a panel with one hand (hot panel by the way---don't tell me you can TURN all of them off, either, cuz some times you just can't--i.e. hospital work) i raise hob with them!!!!! this crap has been spread WAY too long and remember there AIN"T no such thing as an OLD STUPID electrician (or high voltage tinkerer) they won't grow old!!! ENGAGE BRAIN---THINK ABOUT IT TWICE---CHECK THAT HIGH VOLTAGE HAS BLED OFF---THEN AND ONLY THEN USE BOTH HANDS steve w5set@alltel.net -----Original Message----- From: Barry Kirkwood To: Mike Baker ; AMPS REFLECTOR ; Jean-Michel Bombar Date: Wednesday, October 10, 2001 4:21 PM Subject: Re: [AMPS] Help building mono band amp > >Yep, >similar 2x813 amp in older "Radio Handbook" by Bill Orr. A proven performer. >73 es gl. >end >Barry Kirkwood PhD ZL1DD >Signal Hill Homestay >66 Cory Road >Palm Beach >Waiheke Island 1240 >NEW ZEALAND >www.waiheke.co.nz/signal.htm >----- Original Message ----- >From: Mike Baker >To: AMPS REFLECTOR ; Jean-Michel Bombar > >Sent: Thursday, 11 October, 2001 6:36 AM >Subject: Re: [AMPS] Help building mono band amp > > >> >> Hello, >> Get an ARRL handbook from say, 1965. For several years there was an >> article on building monoband KW amps using a pair of 813's. I used these >> articles as the basis for my very first amp in 1969. 813's are still >> available via various sources including the internet and are quite >> inexpensive. I scrounged around for a year or so on e-bay and made a deal >> with a fellow to buy 9 tubes and 4 sockets for $80 including the shipping. >> 7 tubes were carbon plates (the best ones IMHO) and 2 were the metal >plates. >> One broke in shipping (not carbon,no loss). For any band up to 20 meters >> they kick butt and love high voltage. The book specs say 2500VDC max for >> the plates but up to 3500VDC is commonly used in GG linear service. 4 >tubes >> will give you a comfortable KW out at 2.5 to 3KV. For up to say 750 out >you >> could use two tubes and have an easier time finding the filament >> transformer. (10VAC at 10Amps for two tubes) Used a surplus 150pf cap >for >> my tuning on 40M and made the coil out of copper tubing. The power xfmr >was >> a surplus unit that ran 900VAC at 1A as a voltage doubler. >> Total cost back then (1969) was maybe $30 but you could still build >one >> today for less than a $100 with a little patience and scrounging. The best >> part of building is you get to test and refine a bunch of talents. Sheet >> metal fabrication, wiring or harness making, parts recognition and >purchase, >> electronic design, metal finishing/painting, etc. just to name a few. >> A few caveat come to mind. I mention these to anyone who is >> contemplating building their first amp. >> 1. HIGH VOLTAGE is not just a sticker on the side of a cabinet. It >> is a seductive lover that will KILL you and bring you to room temperature >if >> not respected and the rules of working around it obeyed to the letter. >You >> seldom get a second chance let alone a third to violate the rules. I have >> been blessed with having survived lethal shocks twice and figure that a >> third is not likely so be aware. >> DO NOT put your hands inside a cabinet that has High Voltage (anything >> above 24Volts AC or DC) present. The AC power mains kill more people >every >> year than any other type of electrocution. >> Work with one hand in your pocket. NOT leaning on a grounded metal >> cabinet or desk. >> Always disconnect the mains power and flag or wrap up the plug end so >it >> isn't accidentally reconnected by someone else. (The old story about two >> guys working on a transmitter together and as one guy has his hands inside >> the cabinet, the other finds the plug pulled from the mains and plugs it >> back in without thinking, saying something like, "OH, I found the problem, >> it isn't plugged in; try it NOW!" Room temperature. >> Use a "shorting" stick or discharge stick. In days of old a large >metal >> loop shaped like a large fish hook with a wooden handle and a piece of >braid >> with and alligator clip on one end clipped to ground. Today I would >modify >> that to be a probe type of stick with a non-conductive handle hooked to a >> long string of 2 watt metal film resistors with a total value of about >100K >> Ohms or so. Use it to check the discharged state of the HV caps before you >> start working on the amp. >> Use a shorting clip across the HV to GND and remove it when you are >> done. IF, IF someone accidentally turns on the power while you are inside >> the cabinet, it will/should blow the FUSE or Circuit Breakers and keep you >> from being a dead fish. >> NEVER, NEVER build an amp without proper fusing of the mains. >> NEVER, NEVER bridge the safety devices (fuses or breakers). They have >a >> purpose. >> NEVER, NEVER work on a project involving High Voltage while you are >> exhausted or overly tired. Falling asleep into your work can be deadly. >> Too tired and you do stupid things you might never recover from. >> NEVER, NEVER work on a project involving High Voltage if you are >> intoxicated. Same result as the previous warning. Save the 807's for the >> celebration of a successful days work. >> All of these previous warnings are old hat and inevitable truths to >> staying alive while working around High Voltage as I am sure most would >> agree. Let me add a couple of my own. >> Realizing that the Human nature of things is to do something as long >as >> you can so long as it doesn't hurt you, all of us at some time or another >> have violated one of the rules listed above. Some of us have survived the >> experience. Some of us had Help surviving the experience. >> If you don't know CPR go and learn it. Once you do you will posses a >> skill that you may never have to use (hopefully). But the alternative to >> not knowing it may cost someone their life and it just might be someone >you >> love. My personal feeling is that it should be taught in junior high >school >> and a requirement for a drivers license. It could greatly reduce the risk >of >> death to thousands. Remember, electrocution causes the heart to stop and >> CPR applied immediately after the victim is clear of the danger can make >the >> difference in being back to normal or a "gomer". >> If you must work on a piece of equipment that involves high voltage do >> NOT do it alone. Be sure someone knows where you are and what you are >> doing. Have a buddy give you a hand. (It can be more fun doing these >things >> as a "buddy" project.) There is nothing more unnerving than to have your >> wife come home and find you "well done" and at room temperature out in >your >> garage or in your shack. It ruins their day and yours! >> >> OK, I know this all seems like I am describing the obvious, but it is >> worth repeating. >> It is sort of like meeting a beautiful woman in a club. YOU ONLY GET >> ONE CHANCE TO MAKE A GOOD FIRST IMPRESSION! You will seldom get a second >> chance. >> >> Good luck with your amp project. READ, READ, READ, and if you still >> have questions, at least you know where to ask. In spite of all of the >> banter and sniping at each other on occasion, this is still one of the >best >> resources for information on AMPS. You could never say this group isn't >> passionate about what they are doing. >> Again, good luck. >> Mike Baker K7DD >> k7dd@qwest.net >> ----- Original Message ----- >> From: "Jean-Michel Bombar" >> To: >> Sent: Wednesday, October 10, 2001 12:57 AM >> Subject: [AMPS] Help building mono band amp >> >> >> > >> > Hello, >> > >> > I would like to built my first HF amp, I am thinking of a 1Kw mono band >> amp >> > for the 40M band. >> > Does any of you have any idea of where I could gather informations to >> start >> > this project? >> > >> > Thanks. >> > >> > Jean-Michel, F5MMX >> > >> > >> > -- >> > FAQ on WWW: http://www.contesting.com/FAQ/amps >> > Submissions: amps@contesting.com >> > Administrative requests: amps-REQUEST@contesting.com >> > Problems: owner-amps@contesting.com >> > >> > >> >> >> -- >> FAQ on WWW: http://www.contesting.com/FAQ/amps >> Submissions: amps@contesting.com >> Administrative requests: amps-REQUEST@contesting.com >> Problems: owner-amps@contesting.com >> >> > > > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k7dd@qwest.net Fri Oct 12 07:56:43 2001 From: k7dd@qwest.net (Mike Baker) Date: Thu, 11 Oct 2001 23:56:43 -0700 Subject: [AMPS] SB-220 cooling References: <3.0.5.32.20011008103918.008d4180@pop.abs.adelphia.net> Message-ID: <004c01c152eb$0dafc5e0$ed850d82@speedchoice.com> Hello Pete, I hope you are kidding about running your amp for any extended period of time with the case off; especially a contest. WHY? I can think of about 2600 to 2900 reasons why not too. Because there is just under 3KV exposed and within easy enough reach if not paying attention to where your hand might be headed. Especially in those middle of the nite runs of JA's after you have been at it for 16 + hours already and you decide to make a tweak to the amps adjustments just after making a band change so you can grab a few new multi's and, OOPS! If you are lucky, you only get a really bad burn that heals up a few weeks. If your luck just ran out, well, someone else is going to get a good deal on a "slightly used" SB-220!! If you really insist on doing this please feel free to put me in your will. ;+} All kidding aside, ask yourself a few simple questions. During a contest, have you ever reached up to tune the amp and grabbed the wrong knob? Like the band switch maybe? Tried to tune the amp while it is set to the wrong band? Used the wrong antenna? Forgot the antenna? Grabbed the knob on your antenna tuner instead? If in your time as a ham you have NEVER made one of these faults, go buy a lottery ticket because the rest of us have done it. I can only guess at the number of guys reading this saying to themselves, "yep, did that one. Oh, yea that one too. Nice to know I am not the only one committing these OOPSis." Please read my response to a first time amp builder attached here. I am not implying anything personal about your habits. Just pointing out the faults we all have as human beings. If we are careful, we can make a few mistakes and live to tell the tail. If not, someone else gets to make your XYL a deal on your gear and throws all your QSL's away and you get one last entry in QST under "Silent Keys". Pete, leave the cabinet in place while using it. It will give us all a lot longer to pick on you via e-mail. ;>) Best 73 Mike Baker K7DD k7dd@qwest.net ----- Original Message ----- From: "Pete Smith" To: Sent: Monday, October 08, 2001 7:39 AM Subject: [AMPS] SB-220 cooling > > Well, I resoldered the pin yet again and thoroughly polished the filament > pins, and so far the repair seems to be holding. The socket seems to be > reasonably tight on the filament pins, so I hope it's not socket > replacement time yet. > > This raises a question, though -- I had assumed that the main source of the > heat that melts the pins was heat dissipated inside the tube element. Now > I'm wondering whether it may not be simple resistive heating from imperfect > contact between the pins and the socket. Anyone have a view on which > effect predominates? > > I also notice that my amp seems to breathe a LOT better with the case off > (but the cage and deflector plate in place, of course. A foot away from > the top of the cage I can feel a nice breeze. Perhaps I should just leave > it this way (without the outer case) for contest use. comments? > > 73, Pete N4ZR > > > > > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > > Original response to a question about building a mono band amp. Hello, Get an ARRL handbook from say, 1965. For several years there was an article on building monoband KW amps using a pair of 813's. I used these articles as the basis for my very first amp in 1969. 813's are still available via various sources including the internet and are quite inexpensive. I scrounged around for a year or so on e-bay and made a deal with a fellow to buy 9 tubes and 4 sockets for $80 including the shipping. 7 tubes were carbon plates (the best ones IMHO) and 2 were the metal plates. One broke in shipping (not carbon,no loss). For any band up to 20 meters they kick butt and love high voltage. The book specs say 2500VDC max for the plates but up to 3500VDC is commonly used in GG linear service. 4 tubes will give you a comfortable KW out at 2.5 to 3KV. For up to say 750 out you could use two tubes and have an easier time finding the filament transformer. (10VAC at 10Amps for two tubes) Used a surplus 150pf cap for my tuning on 40M and made the coil out of copper tubing. The power xfmr was a surplus unit that ran 900VAC at 1A as a voltage doubler. Total cost back then (1969) was maybe $30 but you could still build one today for less than a $100 with a little patience and scrounging. The best part of building is you get to test and refine a bunch of talents. Sheet metal fabrication, wiring or harness making, parts recognition and purchase, electronic design, metal finishing/painting, etc. just to name a few. A few caveat come to mind. I mention these to anyone who is contemplating building their first amp. 1. HIGH VOLTAGE is not just a sticker on the side of a cabinet. It is a seductive lover that will KILL you and bring you to room temperature if not respected and the rules of working around it obeyed to the letter. You seldom get a second chance let alone a third to violate the rules. I have been blessed with having survived lethal shocks twice and figure that a third is not likely so be aware. DO NOT put your hands inside a cabinet that has High Voltage (anything above 24Volts AC or DC) present. The AC power mains kill more people every year than any other type of electrocution. Work with one hand in your pocket. NOT leaning on a grounded metal cabinet or desk. Always disconnect the mains power and flag or wrap up the plug end so it isn't accidentally reconnected by someone else. (The old story about two guys working on a transmitter together and as one guy has his hands inside the cabinet, the other finds the plug pulled from the mains and plugs it back in without thinking, saying something like, "OH, I found the problem, it isn't plugged in; try it NOW!" Room temperature. Use a "shorting" stick or discharge stick. In days of old a large metal loop shaped like a large fish hook with a wooden handle and a piece of braid with and alligator clip on one end clipped to ground. Today I would modify that to be a probe type of stick with a non-conductive handle hooked to a long string of 2 watt metal film resistors with a total value of about 100K Ohms or so. Use it to check the discharged state of the HV caps before you start working on the amp. Use a shorting clip across the HV to GND and remove it when you are done. IF, IF someone accidentally turns on the power while you are inside the cabinet, it will/should blow the FUSE or Circuit Breakers and keep you from being a dead fish. NEVER, NEVER build an amp without proper fusing of the mains. NEVER, NEVER bridge the safety devices (fuses or breakers). They have a purpose. NEVER, NEVER work on a project involving High Voltage while you are exhausted or overly tired. Falling asleep into your work can be deadly. Too tired and you do stupid things you might never recover from. NEVER, NEVER work on a project involving High Voltage if you are intoxicated. Same result as the previous warning. Save the 807's for the celebration of a successful days work. All of these previous warnings are old hat and inevitable truths to staying alive while working around High Voltage as I am sure most would agree. Let me add a couple of my own. Realizing that the Human nature of things is to do something as long as you can so long as it doesn't hurt you, all of us at some time or another have violated one of the rules listed above. Some of us have survived the experience. Some of us had Help surviving the experience. If you don't know CPR go and learn it. Once you do you will posses a skill that you may never have to use (hopefully). But the alternative to not knowing it may cost someone their life and it just might be someone you love. My personal feeling is that it should be taught in junior high school and a requirement for a drivers license. It could greatly reduce the risk of death to thousands. Remember, electrocution causes the heart to stop and CPR applied immediately after the victim is clear of the danger can make the difference in being back to normal or a "gomer". If you must work on a piece of equipment that involves high voltage do NOT do it alone. Be sure someone knows where you are and what you are doing. Have a buddy give you a hand. (It can be more fun doing these things as a "buddy" project.) There is nothing more unnerving than to have your wife come home and find you "well done" and at room temperature out in your garage or in your shack. It ruins their day and yours! OK, I know this all seems like I am describing the obvious, but it is worth repeating. It is sort of like meeting a beautiful woman in a club. YOU ONLY GET ONE CHANCE TO MAKE A GOOD FIRST IMPRESSION! You will seldom get a second chance. Good luck with your amp project. READ, READ, READ, and if you still have questions, at least you know where to ask. In spite of all of the banter and sniping at each other on occasion, this is still one of the best resources for information on AMPS. You could never say this group isn't passionate about what they are doing. Again, good luck. Mike Baker K7DD k7dd@qwest.net ----- Original Message ----- From: "Jean-Michel Bombar" To: Sent: Wednesday, October 10, 2001 12:57 AM Subject: [AMPS] Help building mono band amp > > Hello, > > I would like to built my first HF amp, I am thinking of a 1Kw mono band amp > for the 40M band. > Does any of you have any idea of where I could gather informations to start > this project? > > Thanks. > > Jean-Michel, F5MMX > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From g8gsq@qsl.net Fri Oct 12 08:16:09 2001 From: g8gsq@qsl.net (Steve Thompson) Date: Fri, 12 Oct 2001 08:16:09 +0100 Subject: [AMPS] SB-220 cooling Message-ID: <002b01c152ed$c5381bc0$b4b801d5@jackie> -----Original Message----- From: Mike Baker To: Pete Smith Cc: AMPS REFLECTOR Date: 12 October 2001 08:02 Subject: Re: [AMPS] SB-220 cooling > >Hello Pete, > I hope you are kidding about running your amp for any extended period >of time with the case off; especially a contest. WHY? I can think of >about 2600 to 2900 reasons why not too. Why not make an alternative cover from wire mesh or somesuch for HD contest use. Lets the air through a treat, but stops fingers. Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From n4zr@contesting.com Fri Oct 12 11:41:40 2001 From: n4zr@contesting.com (Pete Smith) Date: Fri, 12 Oct 2001 06:41:40 -0400 Subject: [AMPS] SB-220 cooling In-Reply-To: <002b01c152ed$c5381bc0$b4b801d5@jackie> Message-ID: <3.0.5.32.20011012064140.008c1a70@pop.abs.adelphia.net> At 08:16 AM 10/12/01 +0100, Steve Thompson wrote: > > >-----Original Message----- >From: Mike Baker >To: Pete Smith >Cc: AMPS REFLECTOR >Date: 12 October 2001 08:02 >Subject: Re: [AMPS] SB-220 cooling > > >> >>Hello Pete, >> I hope you are kidding about running your amp for any extended period >>of time with the case off; especially a contest. WHY? I can think of >>about 2600 to 2900 reasons why not too. > >Why not make an alternative cover from wire mesh or somesuch for HD contest >use. Lets the air through a treat, but stops fingers. Steve, the SB-220 has an internal cover that already accomplishes what you describe, with an interlock that shorts the HV to ground if it is removed. I probably won't need to do this anyway, because I've just received the higher-capacity cooling fan I ordered from Harbach -- good service from the new owner, Jeff, W8CQ... 73, Pete N4ZR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From g8gsq@qsl.net Fri Oct 12 13:18:23 2001 From: g8gsq@qsl.net (Steve Thompson) Date: Fri, 12 Oct 2001 13:18:23 +0100 Subject: [AMPS] SB-220 cooling Message-ID: <002701c15318$05157f60$354f7ad5@office> -----Original Message----- From: Pete Smith To: Steve Thompson ; amps@contesting.com Date: 12 October 2001 12:11 Subject: Re: [AMPS] SB-220 cooling >Steve, the SB-220 has an internal cover that already accomplishes what you >describe, with an interlock that shorts the HV to ground if it is removed. Aha, someone got there before me. Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From n2bc@stny.rr.com Fri Oct 12 12:53:15 2001 From: n2bc@stny.rr.com (n2bc@stny.rr.com) Date: Fri, 12 Oct 2001 11:53:15 GMT Subject: [AMPS] SB-220 cooling Message-ID: <200110121202.f9CC2xo10514@mailout5.nyroc.rr.com> Mike brings up an excellent point - "grabbing the wrong knob" Our club has an SB-220. It's used by all manner of folks & in the frenzy of a contest it gets lots of abuse. I found that changing the bandswitch knob to something significantly different (smaller) reduces the cuss words heard through the wee hours. On the cooling thread.... We all operate using headphones - the noise from 'station #2" is always worse than any equipment noise. This said, we have a big muffin fan (10" diameter - BIG!) sitting on top of the SB-220 pulling air out of the cabinet. Makes a huge difference in the internal temps. We throttle the fan back with a normal lamp dimmer switch to abt half speed, the noise really not a problem. It's ugly, but then the '220 looks pretty stupid with that tiny bandswitch knob anyway! pop-server.stny.rr.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From na9d@speakeasy.net Fri Oct 12 13:16:37 2001 From: na9d@speakeasy.net (Jon Ogden) Date: Fri, 12 Oct 2001 07:16:37 -0500 Subject: [AMPS] HV warning In-Reply-To: Message-ID: Very good advice, John. Religiously sticking to safety rules and following procedures will save your life. Do it even if you don't think you need to. It's like operating a firearm. You check the chamber for a bullet every single time you handle it. It only takes once. Such things saved my life as I almost touched a live 6KV anode line because I was certain the power was off on the power supply. But then I thought about my procedures and decided to put my HV probe on the line anyhow (it only took seconds to do and saved my life). The line had HV on it and what I had failed to do was to verify that every breaker on the power supply was off. One was still on. So in fact, double and triple layers of precaution should be used in case you miss something. But the idea of walking into rooms full of cap banks that have been charged with 80KV gives me the willies! YIKES! Oh yes, and never work on HV when you are tired. That's a good bit of advice to! 73, Jon NA9D on 10/11/01 10:41 AM, John T. M. Lyles at jtml@lanl.gov wrote: > > K7DD, Mike Baker, has printed a very detailed and wise treastise on > the hazards of high voltage. Everything he said reminds me of various > accidents and scenarios for accidents which I can remember. I have > never felt the jab of derious DC HV supplies, but have seen others do > it. ------------------------------------- Jon Ogden NA9D (ex: KE9NA) Member: ARRL, AMSAT, DXCC, NRA http://www.qsl.net/ke9na "A life lived in fear is a life half lived." -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From g8gsq@qsl.net Fri Oct 12 13:40:00 2001 From: g8gsq@qsl.net (Steve Thompson) Date: Fri, 12 Oct 2001 13:40:00 +0100 Subject: [AMPS] HV warning Message-ID: <004a01c1531b$03303d40$354f7ad5@office> -----Original Message----- From: Jon Ogden To: John T. M. Lyles ; amps@contesting.com Date: 12 October 2001 13:22 Subject: Re: [AMPS] HV warning > >But the idea of walking into rooms full of cap banks that have been charged >with 80KV gives me the willies! YIKES! Takes me back to my student days. I spent a long summer working on the Marconi Martello radar tx. From memory, the ht cabinet had 140kV in it, delivered 86A during the rf pulse. Lots of work with 3' long insulated prods, trying to look at mV in the control circuits. I saw some good standing jumps when people 'accidentally' dropped steel panel on the hanger floor. Then there was the time that the hose feeding the dummy load split and sprayed water in there. It was a particular sort of misfit seemed to end up in that department. Happy days. Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Wlfuqu00@uky.edu Fri Oct 12 13:26:40 2001 From: Wlfuqu00@uky.edu (wlfuqu00@uky.edu) Date: Fri, 12 Oct 2001 08:26:40 -0400 Subject: [AMPS] Help building mono band amp In-Reply-To: <000001c1520e$6e293a60$6401a8c0@bllvu1.wa.com> References: <004001c151b2$256fd880$ed850d82@speedchoice.com> Message-ID: <5.0.0.25.2.20011012081703.049f9eb0@mail.uky.edu> Why not start with a pair of 4-125A's in grounded grid... They will give you the same output as a pair of 813's and 3KV plate voltage is within their spec. Later by simply beefing up the plate supply and filament transformer and choke you can upgrade to 4-250A or 4-400A or 3-500Z with out changing sockets. You will probably be content with a pair of 4-125A's for some time. Also, don't forget to make a window so you can enjoy the red glow of you plates.... 4-125's are cheap because very few people use them and you are more likely to get new ones than the 813's. Many of the 813's I have gotten at hamfest were abused and usually low on emission. Hams used to push them hard since they were cheap in the 50's and 60's 73 Bill wa4lav At 09:37 PM 10/10/01 -0700, Geo Clute W7LFD wrote: > >-----Original Message----- > >From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On > >Behalf Of Mike Baker > >Sent: Wednesday, October 10, 2001 10:37 AM > >To: AMPS REFLECTOR; Jean-Michel Bombar > >Subject: Re: [AMPS] Help building mono band amp > > For any band up to 20 meters they kick butt and love high voltage. > > >The 813's typical operation is to 30 MHz. I ran a pair on 10 meters >with 3350VDC on the plates. >Drove them with a Swan 500cx until the carbon plates many red >hues...Couldn't burn them out. > >1983 "The Radio Amateur's Handbook" >Freq.: 30 Mc. >Plate V. 2500 >Plate MA 125 >Screen ma. 20 >fil 10v 5A >Screen Volts 800 >Cin PF 16.3 >C gp PF .025 >C out PF 14 > >Typical output AB2 two tubes is 650 W > >Regards, > >Geo W7LFD > > > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Chuck_Partain@Maxtor.com Fri Oct 12 14:38:19 2001 From: Chuck_Partain@Maxtor.com (Partain, Chuck) Date: Fri, 12 Oct 2001 06:38:19 -0700 Subject: [AMPS] parts needed for 4cx-250 amp I am building Message-ID: <378289F42B3FD51185AD0002B3302CF4FF436F@mmaexc01.mma.maxtor.com> OK, I am still on the trail for parts for my HF 4cx-250 amp. I thought I had a plate transformer but that fell thru. Looking for these items now, maybe someone can help. plate transformer ~1500v .5a sk606 ceramic chimmeny and I walked all around the hopkington NH flea market and found no good cases to build the amp in or on. suggestions? A 16x14x4" bud chassis to start on was 60$ at u-do-it electronics! i really didn't wanna go that route. what do other folks use for chassis? thanks! Chuck Partain maXtor Corp Shrewsbury, MA 508-770-3496 -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Joseph.Piatt@aventis.com Fri Oct 12 15:51:09 2001 From: Joseph.Piatt@aventis.com (Joseph.Piatt@aventis.com) Date: Fri, 12 Oct 2001 09:51:09 -0500 Subject: [AMPS] National 2000 Message-ID: I have been helping a friend with their NCL2000. The power cord had been in the same position a very long time, a sharp 90 degree turn, and all the insulation on the wires had cracked. After moving the amp around on the bench it continued to work well on low. However, when in the high position and the plate switch was pressed there was a spark and the plate current would not come on but it would not blow a fuse or trip the breaker. We found one of the wires had the insulation burned back to the plug and replaced the power cord and it appeared all was well. Periodically though he has found that the plate current does not shut off. This is true when the power or plate switch is moved to the off position. The only way to get it to shut off is to unplug the amp and then it works normal for awhile and then happens again. I had this happen to me before on another amp and the AC relay contacts were stuck. Can anyone tell me if that might be the case with this amp? The plate switch no longer has a spark like it used to before the power cord was replaced. Just trying to learn my way around the amps. I have enjoyed the safety conversations and the beer conversations too. Thanks, Joe KC0EDQ -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 12 15:59:02 2001 From: 2@vc.net (2) Date: Fri, 12 Oct 2001 07:59:02 -0700 Subject: [AMPS] SB-220 cooling Message-ID: <200110121458.f9CEwiZ30447@contesting.com> > > >-----Original Message----- >From: Mike Baker >To: Pete Smith >Cc: AMPS REFLECTOR >Date: 12 October 2001 08:02 >Subject: Re: [AMPS] SB-220 cooling > > >> >>Hello Pete, >> I hope you are kidding about running your amp for any extended period >>of time with the case off; especially a contest. WHY? I can think of >>about 2600 to 2900 reasons why not too. > >Why not make an alternative cover from wire mesh or somesuch for HD contest >use. Lets the air through a treat, but stops fingers. > As I recall, with the 220's case off, there is no exposed 3kV. cheers, Steve > > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w8ik@subich.com Fri Oct 12 16:12:55 2001 From: w8ik@subich.com (Joe Subich, K4IK) Date: Fri, 12 Oct 2001 11:12:55 -0400 Subject: [AMPS] SB-220 cooling In-Reply-To: <200110121458.f9CEwiZ30447@contesting.com> Message-ID: From: Measures > > As I recall, with the 220's case off, there is no exposed 3kV. > > Unless I'm mistaken, the "business end" of the capacitor bank and the bleeder string are exposed just behind the right side of the front panel (behind the meters). I don't recall any shield between the capacitor box and front panel. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k7dd@qwest.net Fri Oct 12 16:28:19 2001 From: k7dd@qwest.net (Mike Baker) Date: Fri, 12 Oct 2001 08:28:19 -0700 Subject: [AMPS] parts needed for 4cx-250 amp I am building References: <378289F42B3FD51185AD0002B3302CF4FF436F@mmaexc01.mma.maxtor.com> Message-ID: <003701c15332$85fcec20$ed850d82@speedchoice.com> Hi Chuck, Look up a "Surplus metals" company in your area. We have several here in the greater Phoenix area but my favorite is Davis Metals. They usually have a good selection of surplus alum or stainless sheet and alum angle stock. Add either rivets (not necessarily my favorite buy useful) or counter sunk holes and matching bolts (in SS) or "PEM nuts" will build any manner of chassis or use it to make a reinforced "Pan" type of construction. If the surplus metals folks don't have a sheet metal sheer available then you will have to locate one to use. Sometimes a High School/Junior High School/trade school metal shop has one that the instructor would be willing to make a few cuts for you either for nothing or a small donation to their metals fund. Don't overlook the opportunity to make friends with a metal shop teacher when you can. If you have talents to trade for services, (your into refrigeration or computers or ??? that is his weak spot) you might end up with a nearly life long source of skills and services not normally available to the average ham. Besides, he might get interested in Ham Radio and then you have helped out the hobby and hopefully made a friend. Best 73 Mike Baker K7DD k7dd@qwest.net ----- Original Message ----- From: "Partain, Chuck" To: Sent: Friday, October 12, 2001 6:38 AM Subject: [AMPS] parts needed for 4cx-250 amp I am building > > > > OK, I am still on the trail for parts for my HF 4cx-250 amp. I thought I had > a plate transformer > but that fell thru. Looking for these items now, maybe someone can help. > > plate transformer ~1500v .5a > sk606 ceramic chimmeny > and I walked all around the hopkington NH flea market and found no good > cases to build > the amp in or on. suggestions? A 16x14x4" bud chassis to start on was 60$ at > u-do-it electronics! > i really didn't wanna go that route. what do other folks use for chassis? > > thanks! > > Chuck Partain > maXtor Corp > Shrewsbury, MA > 508-770-3496 > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w2fca@qsl.net Fri Oct 12 16:39:16 2001 From: w2fca@qsl.net (Frank Ayers) Date: Fri, 12 Oct 2001 08:39:16 -0700 Subject: [AMPS] parts needed for 4cx-250 amp I am building Message-ID: <121001285.31146@webbox.com> >--- Original Message --- >From: "Partain, Chuck" > I walked all around the hopkington NH flea market and found no good >cases to build >the amp in or on. suggestions? A 16x14x4" bud chassis to start on was 60$ at >u-do-it electronics! >i really didn't wanna go that route. what do other folks use for chassis? I've used Byers Chassis and had great success. the URL is - http://home.flash.net/~k3iwk/ Frank W2FCA -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w8ik@subich.com Fri Oct 12 16:44:54 2001 From: w8ik@subich.com (Joe Subich, K4IK) Date: Fri, 12 Oct 2001 11:44:54 -0400 Subject: [AMPS] National 2000 In-Reply-To: Message-ID: > I had this happen to me before on another amp and the AC > relay contacts were stuck. Can anyone tell me if that might be > the case with this amp? The plate switch no longer has a spark > like it used to before the power cord was replaced. I suspect you've answered your own question if you think about it. The plate power switch is probably "welded" in on position. Unplug the amplifier, discharge the capacitors and then check the plate switch. 73, ... Joe, K4IK -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 12 17:47:28 2001 From: 2@vc.net (2) Date: Fri, 12 Oct 2001 09:47:28 -0700 Subject: [AMPS] SB-220 cooling Message-ID: <200110121647.f9CGlAZ00472@contesting.com> > > >From: Measures > >> >> As I recall, with the 220's case off, there is no exposed 3kV. >> >> > >Unless I'm mistaken, the "business end" of the capacitor bank >and the bleeder string are exposed just behind the right side >of the front panel (behind the meters). I don't recall any shield >between the capacitor box and front panel. > // Surely. So what kind of a schmo is going to slide his hand down into the HV supply? With part of the hand touching gnd, loosing part of a finger would be the likely result. Even with the case on, the SB-220 is not fool-proof because it is possible to insert a piece of 22-gauge insulated wire through the top and touch either anode. Cheers, Joe > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 12 17:47:31 2001 From: 2@vc.net (2) Date: Fri, 12 Oct 2001 09:47:31 -0700 Subject: [AMPS] National 2000 Message-ID: <200110121647.f9CGlCZ00476@contesting.com> > > > >> I had this happen to me before on another amp and the AC >> relay contacts were stuck. Can anyone tell me if that might be >> the case with this amp? The plate switch no longer has a spark >> like it used to before the power cord was replaced. > >I suspect you've answered your own question if you think about it. >The plate power switch is probably "welded" in on position. >Unplug the amplifier, discharge the capacitors and then check the >plate switch. > // Perhaps the NCL-2000 needs a stepstart ckt for the same reason that the TL-922 needs one? - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 12 17:47:32 2001 From: 2@vc.net (2) Date: Fri, 12 Oct 2001 09:47:32 -0700 Subject: [AMPS] parts needed for 4cx-250 amp I am building Message-ID: <200110121647.f9CGlDZ00480@contesting.com> > >Hi Chuck, > Look up a "Surplus metals" company in your area. We have several here >in the greater Phoenix area but my favorite is Davis Metals. They usually >have a good selection of surplus alum or stainless sheet and alum angle >stock. Add either rivets (not necessarily my favorite buy useful) or >counter sunk holes and matching bolts (in SS) or "PEM nuts" will build any >manner of chassis or use it to make a reinforced "Pan" type of construction.... // Amen, Mike. PEM nut photos are on my Web site -- as well as photos of an amplifier built with PEM nuts. - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w8ik@subich.com Fri Oct 12 19:35:48 2001 From: w8ik@subich.com (Joe Subich, K4IK) Date: Fri, 12 Oct 2001 14:35:48 -0400 Subject: [AMPS] SB-220 cooling In-Reply-To: <200110121647.f9CGlAZ00472@contesting.com> Message-ID: > From: Measures > > > > > > >From: Measures > > > >> > >> As I recall, with the 220's case off, there is no exposed 3kV. > >> > >> > > > >Unless I'm mistaken, the "business end" of the capacitor bank > >and the bleeder string are exposed just behind the right side > >of the front panel (behind the meters). I don't recall any shield > >between the capacitor box and front panel. > > > // Surely. So what kind of a schmo is going to slide his hand down into > the HV supply? With part of the hand touching gnd, loosing part of a > finger would be the likely result. Even with the case on, the SB-220 is > not fool-proof because it is possible to insert a piece of 22-gauge > insulated wire through the top and touch either anode. > All it takes is an unintentional "slip" during a contest (knock something off an adjacent shelf). That's the point ... not that someone will intentionally reach into that area ... but that it is open in spite of your statement that there is no exposed 3KV. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From K7xq@aol.com Fri Oct 12 19:57:17 2001 From: K7xq@aol.com (K7xq@aol.com) Date: Fri, 12 Oct 2001 14:57:17 EDT Subject: [AMPS] SB-220 Plate Voltage / Output Problem Message-ID: <130.2f53e9f.28f8970e@aol.com> I recently try using my SB-220 on 15 and 10 meter trying to break a pile up and found it was only putting out only 200 watts Max regardless of grid drive and up to 500 ma Plate Current( saturated output with 20 watts input) . In looking at the Plate HV Voltage, I am only seeing 1500 VDC ( shouldnt it be @ 3000 VDC ??? )on standby unloaded. It looks like my Voltage Doubler has failed somewhere. It is wired for 110 VAC and there is no noticable damage components and wiring inside the unit. What component would be the likely candidate to replace ??? My DVM is only rated for 1000 VDC so how do I go about troubleshooting the voltage doubler to find the bad part or problem ??? Jeff K7XQ -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From royanjoy@ncn.net Fri Oct 12 20:23:41 2001 From: royanjoy@ncn.net (Roy Koeppe) Date: Fri, 12 Oct 2001 14:23:41 -0500 Subject: [AMPS] Re: SB-220 cooling Message-ID: <000b01c15353$67bb3e80$442448ce@ncn.net> Said, and right on, "Surely. So what kind of a schmo is going to slide his hand down into the HV supply?" Exactly...driving down the freeway at 70 mph requires just a little inadvertent tug on the steering wheel to cause you to meet your maker. Who would ever deliberately stick his hand down into the infernal PA tank or HV supply? What a topic. 73, Roy K6XK/0 -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 12 22:17:51 2001 From: 2@vc.net (2) Date: Fri, 12 Oct 2001 14:17:51 -0700 Subject: [AMPS] SB-220 cooling Message-ID: <200110122117.f9CLHVZ05855@contesting.com> > > > >> From: Measures >> >> > >> > >> >From: Measures >> > >> >> >> >> As I recall, with the 220's case off, there is no exposed 3kV. >> >> >> >> >> > >> >Unless I'm mistaken, the "business end" of the capacitor bank >> >and the bleeder string are exposed just behind the right side >> >of the front panel (behind the meters). I don't recall any shield >> >between the capacitor box and front panel. >> > >> // Surely. So what kind of a schmo is going to slide his hand down into >> the HV supply? With part of the hand touching gnd, loosing part of a >> finger would be the likely result. Even with the case on, the SB-220 is >> not fool-proof because it is possible to insert a piece of 22-gauge >> insulated wire through the top and touch either anode. >> > >All it takes is an unintentional "slip" during a contest (knock something >off an adjacent shelf). How does the something that falls touch the filter cap assy and simultaneously touch the contest operator? >That's the point ... not that someone will >intentionally reach into that area ... but that it is open in spite of >your statement that there is no exposed 3KV. > What if lightning strikes the antenna? Cheers, Joe - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 12 22:17:54 2001 From: 2@vc.net (2) Date: Fri, 12 Oct 2001 14:17:54 -0700 Subject: [AMPS] Re: SB-220 cooling Message-ID: <200110122117.f9CLHYZ05864@contesting.com> > >Said, and right on, > > "Surely. So what kind of a schmo is going to slide his hand down into >the HV supply?" > >Exactly...driving down the freeway at 70 mph requires just a little >inadvertent tug on the steering wheel to cause you to meet your maker. >Who would ever deliberately stick his hand down into the infernal PA >tank or HV supply? > // Chortle. Since the tank is sans-DC, the tank would only give RF burns. The +HV supply is a whole nuther ballgame. >What a topic. > cheers, Roy - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 12 22:17:52 2001 From: 2@vc.net (2) Date: Fri, 12 Oct 2001 14:17:52 -0700 Subject: [AMPS] SB-220 Plate Voltage / Output Problem Message-ID: <200110122117.f9CLHXZ05859@contesting.com> > > >I recently try using my SB-220 on 15 and 10 meter trying to break a pile >up and found it was only putting out only 200 watts Max regardless of grid >drive and up to 500 ma Plate Current( saturated output with 20 watts >input) . In looking at the Plate HV Voltage, I am only seeing 1500 VDC ( >shouldnt it be @ 3000 VDC ??? )on standby unloaded. It looks like my >Voltage Doubler has failed somewhere. It is wired for 110 VAC and there is >no noticable damage components and wiring inside the unit. >What component would be the likely candidate to replace ??? >My DVM is only rated for 1000 VDC so how do I go about troubleshooting the >voltage doubler to find the bad part or problem ??? > Measure the R of the three 4.7M� resistors to see if the voltmeter is the problem. If you have normal ouput on 40m, my guess is crispy-crittered bandswitch contacts on 10m and 15m. . good luck, Jeff - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w8ik@subich.com Fri Oct 12 23:23:18 2001 From: w8ik@subich.com (Joe Subich, K4IK) Date: Fri, 12 Oct 2001 18:23:18 -0400 Subject: [AMPS] SB-220 cooling In-Reply-To: <200110122117.f9CLHd509243@marconi.swl.net> Message-ID: > From: Measures > > > >All it takes is an unintentional "slip" during a contest (knock something > >off an adjacent shelf). > > How does the something that falls touch the filter cap assy and > simultaneously touch the contest operator? > As usual, when shown to be wrong you point in a different direction. Without the case, lethal voltages are exposed in the SB-200. If the operator is careful, it is not a problem. If the operator is sloppy, the operator will wear a pine case ... I can certainly see a spare pen/pencil falling into the (open) power supply area of a SB-220 and an operator absentmindedly reaching for it at 4 AM local the second night of a contest. > What if lightning strikes the antenna? Nothing, if the station is properly designed. 73, ... Joe, K4IK -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Sat Oct 13 02:21:56 2001 From: W8JI@contesting.com (Tom Rauch) Date: Fri, 12 Oct 2001 21:21:56 -0400 Subject: [AMPS] SB-220 cooling In-Reply-To: References: <200110122117.f9CLHd509243@marconi.swl.net> Message-ID: <3BC75EF4.31394.15802315@localhost> > > How does the something that falls touch the filter cap assy and > > simultaneously touch the contest operator? > > > > As usual, when shown to be wrong you point in a different direction. > Without the case, lethal voltages are exposed in the SB-200. If the > operator is careful, it is not a problem. If the operator is sloppy, > the operator will wear a pine case .. True example. I was working on a HV supply with a resonant choke, and got the choke on the low side or resonance. When I turned the supply on with a meter attached, it blew a 20 or 30kV rated test lead wire in half and the wire came through the air and attached itself to my wrist. One should NEVER take any chances with HV. Only a few idiots try get killed on purpose, most of the time it is something really weird or stupid (like operating a HV supply or PA without a cover) that gets you. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From n4zr@contesting.com Sat Oct 13 02:28:47 2001 From: n4zr@contesting.com (Pete Smith) Date: Fri, 12 Oct 2001 21:28:47 -0400 Subject: [AMPS] SB-220 cooling In-Reply-To: References: <200110121647.f9CGlAZ00472@contesting.com> Message-ID: <3.0.5.32.20011012212847.00b10bd0@pop.abs.adelphia.net> At 02:35 PM 10/12/01 -0400, Joe Subich, K4IK wrote: >> >Unless I'm mistaken, the "business end" of the capacitor bank >> >and the bleeder string are exposed just behind the right side >> >of the front panel (behind the meters). I don't recall any shield >> >between the capacitor box and front panel. This is wrong. I'm sitting here looking at the top of my SB-220 with the cosmetic cover off. There are no gaps in the perforated aluminum shield over the entire top of the amplifier. I would never have suggested operating the amplifier without the cosmetics if any HV was exposed. Very truly yours, and not suicidal, 73, Pete N4ZR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sat Oct 13 02:59:33 2001 From: 2@vc.net (2) Date: Fri, 12 Oct 2001 18:59:33 -0700 Subject: [AMPS] SB-220 cooling Message-ID: <200110130159.f9D1xDZ11640@contesting.com> > > > >> From: Measures >> > >> >All it takes is an unintentional "slip" during a contest (knock something >> >off an adjacent shelf). >> >> How does the something that falls touch the filter cap assy and >> simultaneously touch the contest operator? >> > >As usual, when shown to be wrong you point in a different direction. // I looked at my SB-220 before I wrote the "wrong" reply. >Without the case, lethal voltages are exposed in the SB-200. If the >operator is careful, it is not a problem. If the operator is sloppy, >the operator will wear a pine case ... > // As in sloppy from too many 811s? >I can certainly see a spare pen/pencil falling into the (open) power >supply area of a SB-220 and an operator absentmindedly reaching for it >at 4 AM local the second night of a contest. > >> What if lightning strikes the antenna? > >Nothing, if the station is properly designed. > Cheers, Joe - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sat Oct 13 03:14:16 2001 From: 2@vc.net (2) Date: Fri, 12 Oct 2001 19:14:16 -0700 Subject: [AMPS] SB-220 cooling Message-ID: <200110130213.f9D2DtZ11936@contesting.com> > >At 02:35 PM 10/12/01 -0400, Joe Subich, K4IK wrote: >>> >Unless I'm mistaken, the "business end" of the capacitor bank >>> >and the bleeder string are exposed just behind the right side >>> >of the front panel (behind the meters). I don't recall any shield >>> >between the capacitor box and front panel. > >This is wrong. I'm sitting here looking at the top of my SB-220 with the >cosmetic cover off. There are no gaps in the perforated aluminum shield >over the entire top of the amplifier. > Groupies will say/recall virtually anything to please their leader and vice-versa. It's a symbiotic relationship. cheers, Pete - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ws7l@arrl.net Sat Oct 13 05:32:42 2001 From: ws7l@arrl.net (Carl Clawson) Date: Fri, 12 Oct 2001 21:32:42 -0700 Subject: [AMPS] Hand in the pocket? Message-ID: We've again recently heard the old rule about keeping one hand in a pocket when working on electronics. I've heard it so many times over so many years that I'm beginning to wonder if it's even true. Is there any evidence that one's overall safety is improved by keeping a hand in a pocket? Who came up with this rule? When? Why? -- Carl WS7L -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From KG6DV@cs.com Sat Oct 13 06:07:03 2001 From: KG6DV@cs.com (KG6DV@cs.com) Date: Sat, 13 Oct 2001 01:07:03 EDT Subject: [AMPS] Hand in pocket test Message-ID: <36.1d108d4c.28f925f7@cs.com> --part1_36.1d108d4c.28f925f7_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit You ask if the "hand in pocket" rule has any basis ... there is an easy test. 1. put one hand in your pocket 2. stand on the concrete floor and reach into the hv section of any amp 3. if you got shocked the rule is bogus and we have all learned something 4. if you didnt get shocked, try the test again. Ron KH6DV --part1_36.1d108d4c.28f925f7_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit You ask if the "hand in pocket" rule has any basis ... there is an easy test.

1. put one hand in your pocket
2. stand on the concrete floor and reach into the hv section of any amp
3. if you got shocked the rule is bogus and we have all learned something
4. if you didnt get shocked, try the test again.

Ron KH6DV

--part1_36.1d108d4c.28f925f7_boundary-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sat Oct 13 06:35:09 2001 From: 2@vc.net (2) Date: Fri, 12 Oct 2001 22:35:09 -0700 Subject: [AMPS] Hand in pocket test Message-ID: <200110130534.f9D5YmZ14987@contesting.com> >You ask if the "hand in pocket" rule has any basis ... there is an easy test. > >1. put one hand in your pocket >2. stand on the concrete floor and reach into the hv section of any amp >3. if you got shocked the rule is bogus and we have all learned something >4. if you didnt get shocked, try the test again. > I have often contacted several kV from a hi-pot while standing on insulating material. I did not conduct. cheers, Ron - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k7fm@teleport.com Sat Oct 13 06:51:44 2001 From: k7fm@teleport.com (Lamb) Date: Fri, 12 Oct 2001 22:51:44 -0700 Subject: [AMPS] Hand in pocket test References: <36.1d108d4c.28f925f7@cs.com> Message-ID: <000101c153ab$38be6780$403e1ad8@colinlam> With the warnings about hands in the power supply, let me tell you a story about my younger days (age 15, 40 years ago) I was measuring the length of a zip cord to wire to a switch which was surface mounted on a desk for my novice station. I plugged it in to get the proper length but then forgot that it was plugged in. It was the right length, so I looked around for my wire strippers but could not find them. So, I split the wire and stuck the wire in my mouth and removed the insulation with my teeth (both sides). No problem. I then began to wire to the switch, but figured out a more sanitary way to run the wire - which required a shorter length of zip cord. So I picked up the wire cutters and cut the zip cord. Suddenly, a spark, a portion of my wire cutter was blown off and the circuit breaker on the main panel was tripped. It was then that I realized I had been very lucky. As a result of this experience (and being knocked across the room when I grabbed the high voltage of my open power supply at age 16, knocking the closet doors off the track), I have been more careful. I figured I used up most of my luck. My last 40 years have been uneventful. Moral - even keeping both hands out of your high voltage supply may not protect you if you do something really stupid - unless you are really lucky. Colin K7FM -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k7dd@qwest.net Sat Oct 13 08:21:48 2001 From: k7dd@qwest.net (Mike Baker) Date: Sat, 13 Oct 2001 00:21:48 -0700 Subject: [AMPS] HV warning References: <004a01c1531b$03303d40$354f7ad5@office> Message-ID: <006801c153b7$b930fac0$ed850d82@speedchoice.com> When I was a new ham and a senior in High School I had a friend and fellow ham who worked at Sandia Labs in Albuquerque about 1970. He told me they were working on a new "cannon" project for Uncle Sam but it was weird because it didn't use a powder charge, it used electricity. A few weeks after telling me about this, we had a big power "blink" late one afternoon. The following day I ran into him at the scrap yard at Sandia and he dragged me off to see a bit of what he was working on. At the time it all looked pretty weird to me and didn't make a lot of sense. Man, I didn't realize what I had been privy too that day until maybe 10 years later. The first "plasma cannon. It would shoot an electrical charge through probes inserted into this "super cooled" chamber and electrically blast a carbon sphere (Diamond?) and divert the energy down a "barrel" that was underground and super cooled to a waiting "target" on the other end and some distance away. (Distance unknown.) I was told that the "target" consisted of a foot of the toughest armor plate known on top of 3 feet of reinforced and layered concrete (sort of like a vertical sandwich). The carbon ball was about 1/4 inch in dia. The blast damage at the other end was described as "unbelievable". So what has this got to do with the subject? I was taken to the underground "Power Accumulator Center" to see the size of the storage devices used to power the "cannon". The room was about 40 X 50 and 4 stories DEEP under several feet of earth and concrete. There was large copper tubes (6inch) running all over the place and I was told that they ran full of liquid nitrogen when the test was under way. All around me were large boxes the size of a large home refrigerator/freezer with huge ceramic/porcelain insulators on top of them that connected to the copper pipes. 3 of the 4 floor of the building were full of them. I have no idea what their value was nor was I told how much voltage they were made for but the one voltmeter I did see measured 0 to 5 MEGAVOLTS and I can't even begin to think how much the Amperage was. This was impressive enough but what he told me next gave me chills. He said that it took 3 days to siphon off enough energy to charge the system without being too obvious but when you first connected it to the "mains" it surged a bit and caused the lights on that end of town to dim for a second or so. All personnel were isolated away from the system when it was fired BUT were INSIDE during the charging time, walking about keeping an eye open for leaks in the cooling system and wearing special safety suits designed to insulate them from the system and provide a safe breathing atmosphere. Sort of like a space suit. He said as the system charged up, even inside the suits, you could still feel the hairs on your body stand up and you would get these mini sparks like you get from a wool carpet at various places within the suit. Even the placement of the runs of conductors were carefully placed to eliminate magnetic reaction (solenoid) otherwise the system would short out with DISASTROUS results. To say I was amazed is a vast understatement. I walked around inside the building "drop jawed" during most of his tour. A few days later (a weekend as I recall) I ran into him again and was invited to stop buy for a few moments so I could "feel" the power of the system. I couldn't resist. He was right. It was the most awesome sensation of pure stored power I have ever felt. I can honestly say looking back on the event that it held a mixture of emotions akin to a roller coaster ride and playing Russian roulette, at the same time! Excitement, Fear, Awe, and the mixture of wanting to run for safety and watch the events unfold. It has remained the greatest "rush" I think I have ever had. I only wish I could have seen an actual firing. For all of the work involved in building that project, it apparently didn't last too long as there was more heavy equipment working on the "secured area" later that summer and from what I heard later through the grapevine, it all went away and became a part of history no one but a select few have memories about. For me it left an impression I will NEVER forget. To quote Darth Vader, "feel the power Luke." Mike Baker K7DD k7dd@qwest.net ----- Original Message ----- From: "Steve Thompson" To: Sent: Friday, October 12, 2001 5:40 AM Subject: Re: [AMPS] HV warning > > > -----Original Message----- > From: Jon Ogden > To: John T. M. Lyles ; amps@contesting.com > > Date: 12 October 2001 13:22 > Subject: Re: [AMPS] HV warning > > > > > >But the idea of walking into rooms full of cap banks that have been charged > >with 80KV gives me the willies! YIKES! > Takes me back to my student days. I spent a long summer working on the > Marconi Martello radar tx. From memory, the ht cabinet had 140kV in it, > delivered 86A during the rf pulse. Lots of work with 3' long insulated > prods, trying to look at mV in the control circuits. I saw some good > standing jumps when people 'accidentally' dropped steel panel on the hanger > floor. Then there was the time that the hose feeding the dummy load split > and sprayed water in there. > > It was a particular sort of misfit seemed to end up in that department. > Happy days. > > Steve > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From JimMoci@aol.com Sat Oct 13 13:29:00 2001 From: JimMoci@aol.com (JimMoci@aol.com) Date: Sat, 13 Oct 2001 08:29:00 EDT Subject: [AMPS] HAND IN POCKET VALIDITY Message-ID: --part1_ad.11c31f39.28f98d8c_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit >You ask if the "hand in pocket" rule has any basis ... there is an easy test. >1. put one hand in your pocket >2. stand on the concrete floor and reach into the hv section of any amp >3. if you got shocked the rule is bogus and we have all learned something >4. if you didnt get shocked, try the test again. >Ron KH6DV I will try this- if you dont hear back from me in 10 minutes you know it didnt work! Jim W3ATV --part1_ad.11c31f39.28f98d8c_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit >You ask if the "hand in pocket" rule has any basis ... there is an easy test.
>1. put one hand in your pocket
>2. stand on the concrete floor and reach into the hv section of any amp
>3. if you got shocked the rule is bogus and we have all learned something
>4. if you didnt get shocked, try the test again.
>Ron KH6DV

I will try this- if you dont hear back from me in 10 minutes you know it didnt work!

Jim W3ATV

--part1_ad.11c31f39.28f98d8c_boundary-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From phil@vaxxine.com Sat Oct 13 15:53:03 2001 From: phil@vaxxine.com (Phil (VA3UX)) Date: Sat, 13 Oct 2001 10:53:03 -0400 Subject: [AMPS] Hand in pocket test In-Reply-To: <36.1d108d4c.28f925f7@cs.com> Message-ID: <5.0.2.1.0.20011013104539.009f2730@vaxxine.com> --=====================_1062495==_.ALT Content-Type: text/plain; charset="us-ascii"; format=flowed I hope this is "tongue-in-cheek". For the less experienced members reading the list, the following procedure (posted below) is practically guaranteed to result in a payout by your life insurance policy to your beneficiary. The "hand in the pocket" rule assumes that your two hands are the only possible points for electrical conduction. Keeping one hand in a pocket removes one of the two conductors, therefore no current can flow. Any body that stands on a bare concrete floor while working on electrical appliances should consider taking up another hobby. Phil At 01:07 AM 10/13/2001 -0400, you wrote: >You ask if the "hand in pocket" rule has any basis ... there is an easy test. > >1. put one hand in your pocket >2. stand on the concrete floor and reach into the hv section of any amp >3. if you got shocked the rule is bogus and we have all learned something >4. if you didnt get shocked, try the test again. > >Ron KH6DV --=====================_1062495==_.ALT Content-Type: text/html; charset="us-ascii" I hope this is "tongue-in-cheek".

For the less experienced members reading the list, the following procedure (posted below) is practically guaranteed to result in a payout by your life insurance policy to your beneficiary.

The "hand in the pocket" rule assumes that your two hands are the only possible points for electrical conduction. Keeping one hand in a pocket removes one of the two conductors, therefore no current can flow. Any body that stands on a bare concrete floor while working on electrical appliances should consider taking up another hobby.

Phil

At 01:07 AM 10/13/2001 -0400, you wrote:

You ask if the "hand in pocket" rule has any basis ... there is an easy test.

1. put one hand in your pocket
2. stand on the concrete floor and reach into the hv section of any amp
3. if you got shocked the rule is bogus and we have all learned something
4. if you didnt get shocked, try the test again.

Ron KH6DV

--=====================_1062495==_.ALT-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ToddRoberts2001@aol.com Sat Oct 13 16:33:54 2001 From: ToddRoberts2001@aol.com (ToddRoberts2001@aol.com) Date: Sat, 13 Oct 2001 11:33:54 EDT Subject: [AMPS] Hand in the pocket? Message-ID: <140.30582d6.28f9b8e2@aol.com> Carl, I think the main reason to keep one hand in a pocket while working around high voltage is to avoid an electrical path from both arms through the heart, as well as limiting the ways one can get shocked. If one hand is grounded and the other hand touches high voltage then the path through the body goes right through the heart muscle increasing the risk of heart failure. If the current went through one hand to ground through your leg at least it wouldn't go through your heart muscle increasing your chances of survival. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sat Oct 13 22:35:23 2001 From: 2@vc.net (2) Date: Sat, 13 Oct 2001 14:35:23 -0700 Subject: [AMPS] Harbach's URL? Message-ID: <200110132135.f9DLZ1Z27876@contesting.com> I NEED THE URL FOR HARBACH ELECTRONICS TNX - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ly3nml@centras.lt Sat Oct 13 21:45:28 2001 From: ly3nml@centras.lt (Gintaras) Date: Sat, 13 Oct 2001 23:45:28 +0300 Subject: [AMPS] Harbach's URL? References: <200110132135.f9DLZ1Z27876@contesting.com> Message-ID: <000f01c15427$ffd52120$0203010a@Gintaras> ----- Original Message ----- From: "2" <2@vc.net> To: "AMPS" Sent: Sunday, October 14, 2001 12:35 AM Subject: [AMPS] Harbach's URL? > > I NEED THE URL FOR HARBACH ELECTRONICS > > TNX > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. > end http://www.harbachelectronics.com/main.html Regards, LY3NML http://ly1dq.hypermart.net -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Kenneth D. Grimm, K4XL" Message-ID: <011001c15432$37ea8960$0200a8c0@wch.adelphia.net> > Joseph Ingram email: mssybil@bellsouth.net > > Son-in-law lost high voltage xfmr in his sb221. Heard > about any sources which are reasonable? Dahl wants > enough to make it worthwhile to find another used > unit. Gary Brown gbrown@mint.net has been talking about starting a transformer rewinding business. I believe that he indicated that he would use the old core to keep the cost down. I would check with him before replacing the old one with a Dahl that would cost almost as much as the amp is worth. Having said that, I am extremely happy with the transformers that I have bought from Dahl. Like the proverbial Timex, "They take a licking and keep on ticking." 73, Ken K4XL k4xl@arrl.net *** BoatAnchor Manual Archive *** On the web at http://bama.sbc.edu or FTP site info: bama.sbc.edu login: anonymous p/w: youremailadr -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From phil@vaxxine.com Sun Oct 14 01:12:52 2001 From: phil@vaxxine.com (Phil (VA3UX)) Date: Sat, 13 Oct 2001 20:12:52 -0400 Subject: [AMPS] SB-221 High Voltage Transformer In-Reply-To: <011001c15432$37ea8960$0200a8c0@wch.adelphia.net> References: <20011011034508.72260.qmail@web20508.mail.yahoo.com> Message-ID: <5.0.2.1.0.20011013201154.009f4680@vaxxine.com> At 05:58 PM 10/13/2001 -0400, you wrote: > > Joseph Ingram email: mssybil@bellsouth.net > > > > Son-in-law lost high voltage xfmr in his sb221. Heard > > about any sources which are reasonable? Dahl wants > > enough to make it worthwhile to find another used > > unit. > >Gary Brown gbrown@mint.net has been talking about starting a transformer >rewinding business. I believe that he indicated that he would use the >old core to keep the cost down. Here's Gary's URL. Click on the "Transformer Rewinding" link near the top of the page. http://tubes_tubes_tubes.tripod.com/tubestubestubes/ Phil -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sun Oct 14 01:14:34 2001 From: 2@vc.net (2) Date: Sat, 13 Oct 2001 17:14:34 -0700 Subject: [AMPS] Harbach's URL? Message-ID: <200110140014.f9E0ECZ30154@contesting.com> Thank you, Gintaras - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sun Oct 14 01:14:37 2001 From: 2@vc.net (2) Date: Sat, 13 Oct 2001 17:14:37 -0700 Subject: [AMPS] SB-221 High Voltage Transformer Message-ID: <200110140014.f9E0EEZ30158@contesting.com> > >> Joseph Ingram email: mssybil@bellsouth.net >> >> Son-in-law lost high voltage xfmr in his sb221. Heard >> about any sources which are reasonable? Dahl wants >> enough to make it worthwhile to find another used >> unit. > >Gary Brown gbrown@mint.net has been talking about starting a transformer >rewinding business. I believe that he indicated that he would use the >old core to keep the cost down. // The Heath transformer is potted. Rewinding it would be a Pandorra's box. >... - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k7fm@teleport.com Sun Oct 14 01:27:54 2001 From: k7fm@teleport.com (Lamb) Date: Sat, 13 Oct 2001 17:27:54 -0700 Subject: [AMPS] SB-221 High Voltage Transformer References: <20011011034508.72260.qmail@web20508.mail.yahoo.com> <5.0.2.1.0.20011013201154.009f4680@vaxxine.com> Message-ID: <001a01c15447$119b82e0$bf3d1ad8@colinlam> Son-in-law lost high voltage xfmr in his sb221 Question: How could he lose it? That seems to be pretty irresponsible. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sun Oct 14 01:26:30 2001 From: 2@vc.net (2) Date: Sat, 13 Oct 2001 17:26:30 -0700 Subject: [AMPS] SB-221 High Voltage Transformer Message-ID: <200110140026.f9E0Q7Z30525@contesting.com> > >Son-in-law lost high voltage xfmr in his sb221 > >Question: How could he lose it? That seems to be pretty irresponsible. > The potting agent is tar. It may be irresponsible to blame anyone. Like Forrest Gump said: "Shit Happens". - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k8cpa@arrl.net Sun Oct 14 04:13:28 2001 From: k8cpa@arrl.net (chuck) Date: Sat, 13 Oct 2001 23:13:28 -0400 Subject: [AMPS] Harbach's URL? In-Reply-To: <200110132135.f9DLZ1Z27876@contesting.com> Message-ID: <3.0.6.32.20011013231328.0083de80@pop3.norton.antivirus> At 02:35 PM 10/13/2001 -0700, you wrote: > >I NEED THE URL FOR HARBACH ELECTRONICS > >TNX HTTP://WWW.HARBACHELECTRONICS.COM -Chuck Adkins K8CPA Drummer, Guitar Player, Ham Radio, Jesus Freak Type Person at Large http://www.qsl.net/k8cpa k8cpa@arrl.net ---------------------------------------------------- Sign Up for NetZero Platinum Today Only $9.95 per month! http://my.netzero.net/s/signup?r=platinum&refcd=PT97 -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From sanil@sancharnet.in Fri Oct 12 18:54:15 2001 From: sanil@sancharnet.in (Anil) Date: Fri, 12 Oct 2001 23:24:15 +0530 Subject: [AMPS] Help building a solid state linear References: <200110101427.f9AERNZ09338@contesting.com> Message-ID: <000c01c1546e$27799620$4630003d@k0a4u6> Hello, I need a help. I have a linear amplifier pate used in Marine HF solid state linear which used 4 such plate and hybrid combiner and giving 1.6kw power output. I've one plate only using two RF transistors SRFE-1058 in push pull and can give approx. 400W output. I've no schematic of this plate and no details about such RF transistors. I need:-- 1. schematic of the plate 2. data of the RF transistors SRFE-1058 3. Powersupply details about such plate. 4. Biasing details. 4. How to connect Solid state TXRX to this plate to give input ? 5. Bandpass filter in the output. 6. relay connection to the antenna I request please give me details and suggest me any website and other source for details. Regards. 73s Anil VU2TRI -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From davisr [wd8jja@arrl.net]" This is a multi-part message in MIME format. ------=_NextPart_000_0037_01C154EE.2DF89520 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: 7bit Hi, I am a new subscriber to the list, but here goes. Does anyone have any experience with calibrating the SWR meter in the FL-2100B?? Mine appears to work okay otherwise, but the SWR reading differs from two other meters in series with it. There is not much difference when looking into a 50 ohm load. But into a trap-vertical, or my tuner, the readings are around 2.0 to 2.5:1 when the other meter(s) read < 1.5:1. If I adjust the tuner so that the FL-2100B shows 1.1 to 1.5, the other meters go up to about 2.5 and the power output drops from about 700 - 800 watts down to around 400 or so. Any help would be appreciated. R_Davis (WD8JJA@arrl.net) ------=_NextPart_000_0037_01C154EE.2DF89520 Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable

Hi, I am a new subscriber to the list, but here goes.

Does anyone have any experience with calibrating the SWR meter in = the=20 FL-2100B??

Mine appears to work okay otherwise, but the SWR reading differs = from two=20 other meters in series with it.

There is not much difference when looking into a 50 ohm load. = But=20 into a trap-vertical, or my tuner,

the readings are around 2.0 to 2.5:1 when the other meter(s) read = <=20 1.5:1.

If I adjust the tuner so that the FL-2100B shows 1.1 to 1.5, the = other=20 meters go up to about 2.5 and the power

output drops from about 700 - 800 watts down to around 400 or so. =

Any help would be appreciated.

R_Davis (WD8JJA@arrl.net)
------=_NextPart_000_0037_01C154EE.2DF89520-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From g8gsq@qsl.net Mon Oct 15 08:00:12 2001 From: g8gsq@qsl.net (Steve Thompson) Date: Mon, 15 Oct 2001 08:00:12 +0100 Subject: [AMPS] FL-2100B SWR Metering Message-ID: <003001c15547$09b3c5a0$b4757ad5@jackie> -----Original Message----- From: davisr [wd8jja@arrl.net] To: amps@contesting.com Date: 15 October 2001 02:27 Subject: [AMPS] FL-2100B SWR Metering >Hi, I am a new subscriber to the list, but here goes. >Does anyone have any experience with calibrating the SWR meter in the >FL-2100B?? >Mine appears to work okay otherwise, but the SWR reading differs from two >other meters in series with it. >There is not much difference when looking into a 50 ohm load. But into a >trap-vertical, or my tuner, >the readings are around 2.0 to 2.5:1 when the other meter(s) read < 1.5:1. >If I adjust the tuner so that the FL-2100B shows 1.1 to 1.5, the other >meters go up to about 2.5 and the power >output drops from about 700 - 800 watts down to around 400 or so. >Any help would be appreciated. The problem arises when a meter doesn't have enough directivity - in other words, some of the forward power leaks into the reverse power detector. Depending on the phase, this adds to or subtracts from the real reverse power, giving a false reading that is higher or lower than real. From what you describe, the FL2100 appears to be wrong. To correct it, you need a load that is known to be a good acurate 50 ohms. Run the amp into it, and adjust the coupler (assuming there are adjustments available) to null the reverse power reading. Worth checking for duff joints and burnt out components first. 73, Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jmbombar@graphnet.fr Mon Oct 15 08:09:20 2001 From: jmbombar@graphnet.fr (Jean-Michel Bombar) Date: Mon, 15 Oct 2001 09:09:20 +0200 Subject: [AMPS] Help building mono band amp References: <004001c151b2$256fd880$ed850d82@speedchoice.com> <5.0.0.25.2.20011012081703.049f9eb0@mail.uky.edu> Message-ID: <014201c15548$5192dc70$678ea8c0@jmb2> I would like to thank all who replied to my help request. Now I think I have enough informations to start my project. Best regards. Jean-Michel, F5MMX -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Mon Oct 15 08:20:35 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Mon, 15 Oct 2001 08:20:35 +0100 Subject: [AMPS] HV warning Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A978@excalibur.swindon.msl.mitel.com> Todd said: >NEVER , EVER work around high voltage after you have had even ONE beer. That's a rule that I follow now, but interestingly, back in the '60s, we often went for a beer or two at lunchtime, and back to work in the afternoon - on high power tx's (30kW and up). Even when testing transformers, a pub lunch wasn't unknown, when transformers were tested open on the bench, with voltages up to 10kV at a few hundred mA. We have a different culture these days, although thinking back, there weren't any accidents caused by HV. Long hair in machines, slipping on oily floors and so on. Interesting. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Mon Oct 15 15:15:41 2001 From: W8JI@contesting.com (Tom Rauch) Date: Mon, 15 Oct 2001 10:15:41 -0400 Subject: [AMPS] Hand in the pocket? In-Reply-To: Message-ID: <3BCAB74D.8265.3A8EDD2@localhost> > Is there any evidence that one's overall safety is improved by keeping > a hand in a pocket? > > Who came up with this rule? When? Why? When I got zapped by the HV lead that flew up and attached itself to my wrist, I was standing on a HV blanket like the kind electric companies use on live power lines. I had one hand "in my pocket", and was working with one hand. I opened a main breaker that was feeding a reversed 4160 pole pig, and burned a half-dollar sized hole in my wrist. The ground path was out my fingers that were flipping the power switch on a grounded panel. The worse burns were at the tips of my fingers and my wrist, and there was very little damage past my middle forearm, that area looked more like a sun tan instead of being charred black or blistered like the area in the current path. I'd hate to think about what would have happened if I was standing on the concrete floor, or had my other hand on a grounded panel. It sure seems to me it saved my life. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jtml@lanl.gov Mon Oct 15 15:29:03 2001 From: jtml@lanl.gov (John T. M. Lyles) Date: Mon, 15 Oct 2001 08:29:03 -0600 Subject: [AMPS] HV warning In-Reply-To: <6CEB3A36096CD2119FEE00A0C9410EC20260A978@excalibur.swindon.msl.mitel.com> References: <6CEB3A36096CD2119FEE00A0C9410EC20260A978@excalibur.swindon.msl.mitel.com> Message-ID: Peter C. said: >That's a rule that I follow now, but interestingly, back in the '60s, we often >went for a beer or two at lunchtime, and back to work in the >afternoon - on high >power tx's (30kW and up). Even when testing transformers, a pub lunch wasn't >unknown, when transformers were tested open on the bench, with voltages up to >10kV at a few hundred mA. > >We have a different culture these days, although thinking back, there weren't >any accidents caused by HV. Long hair in machines, slipping on oily floors and >so on. Interesting. Yes, we did this also. Lunchtime, a few brews, then back to high power RF test work. Even today, a beer at lunch doesn't seem abnormal, but two of them, well, depends on the person. For myself one is adequate, two excessive (at lunch I mean). At CERN, the large particle accelerator complex near Geneva, wine and beer are sold in the cafeteria at lunch. I don't believe that they have lost an excessive # of workers due to it, although they did get sabatoged when someone left a beer bottle inside the evacuated beamline deep inside the tunnel for one of the large synchrotrons there a few years back, and they couldn't get the particles to accelerate past the 'obstruction'. On another note, HF has been erratic this weekend, sometimes 10 is really open. Lots of solar activity going on. 73 John K5PRO -- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Mon Oct 15 15:39:42 2001 From: stevek@jmr.com (Steve Katz) Date: Mon, 15 Oct 2001 07:39:42 -0700 Subject: [AMPS] Hand in pocket test Message-ID: I like my test better: Stand on cement floor, barefooted. Have metal D104 in one hand. Reach in and grab the 4-1000 anode cap (amp on, and transmitting) with the other hand. Wake up six feet away, on floor, feeling dizzy and aching in places you forgot you had. Been there. WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: 2 [SMTP:2@vc.net] > Sent: Friday, October 12, 2001 10:35 PM > To: KG6DV@cs.com; AMPS > Subject: Re: [AMPS] Hand in pocket test > > > >You ask if the "hand in pocket" rule has any basis ... there is an easy > test. > > > >1. put one hand in your pocket > >2. stand on the concrete floor and reach into the hv section of any amp > >3. if you got shocked the rule is bogus and we have all learned something > >4. if you didnt get shocked, try the test again. > > > I have often contacted several kV from a hi-pot while standing on > insulating material. I did not conduct. > > cheers, Ron > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. > end > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Mon Oct 15 17:52:01 2001 From: stevek@jmr.com (Steve Katz) Date: Mon, 15 Oct 2001 09:52:01 -0700 Subject: [AMPS] parts needed for 4cx-250 amp I am building Message-ID: Chuck, I have a suitable transformer, as well as ceramic chimneys for 4CX250s. Can you use a xfmr with 120Vac primary, or do you need it to be 240V? Let me know... 73 Steve WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Partain, Chuck [SMTP:Chuck_Partain@Maxtor.com] > Sent: Friday, October 12, 2001 6:38 AM > To: 'amps@contesting.com' > Subject: [AMPS] parts needed for 4cx-250 amp I am building > > > > > OK, I am still on the trail for parts for my HF 4cx-250 amp. I thought I > had > a plate transformer > but that fell thru. Looking for these items now, maybe someone can help. > > plate transformer ~1500v .5a > sk606 ceramic chimmeny > and I walked all around the hopkington NH flea market and found no good > cases to build > the amp in or on. suggestions? A 16x14x4" bud chassis to start on was 60$ > at > u-do-it electronics! > i really didn't wanna go that route. what do other folks use for chassis? > > thanks! > > Chuck Partain > maXtor Corp > Shrewsbury, MA > 508-770-3496 > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From bobs@isquare.com Mon Oct 15 19:36:08 2001 From: bobs@isquare.com (Bob Sullivan) Date: Mon, 15 Oct 2001 14:36:08 -0400 Subject: [AMPS] 4CX1500 question Message-ID: <5.1.0.14.2.20011015143501.00fbe800@mail.bscnet.com> Has anyone heard of a 4CX1500BM (also known as a "Y757") made by Eimac for the military? How is it different, if at all, from a 4CX1500B? Thanks! 73, Bob W0YVA -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Ken Barber" This is a multi-part message in MIME format. ------=_NextPart_000_0005_01C155B4.40726E80 Content-Type: multipart/alternative; boundary="----=_NextPart_001_0006_01C155B4.40726E80" ------=_NextPart_001_0006_01C155B4.40726E80 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Looks like the 4CX1500BM is good up to 30 MHZ. The 4CX1500B is good up = to 110 MHZ. 73, Ken W2DTC = http://catalog.rell.com/rellecom/scripts/SkuPage.asp?SKU=3D176223&PNO=3D&= PNM=3D ------=_NextPart_001_0006_01C155B4.40726E80 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Looks like the = 4CX1500BM is good=20 up to 30 MHZ. The 4CX1500B is good up to 110 = MHZ.

73,

Ken = W2DTC

http://catalog.rell.com/rellecom/scripts/SkuPage.asp= ?SKU=3D176223&PNO=3D&PNM=3D ------=_NextPart_001_0006_01C155B4.40726E80-- ------=_NextPart_000_0005_01C155B4.40726E80 Content-Type: application/octet-stream; name="Richardson Electronics, Ltd..url" Content-Transfer-Encoding: quoted-printable Content-Disposition: attachment; filename="Richardson Electronics, Ltd..url" [DEFAULT] BASEURL=3Dhttp://catalog.rell.com/rellecom/scripts/SkuPage.asp?SKU=3D1762= 23&PNO=3D&PNM=3D [InternetShortcut] URL=3Dhttp://catalog.rell.com/rellecom/scripts/SkuPage.asp?SKU=3D176223&P= NO=3D&PNM=3D Modified=3D20E02078D555C10184 ------=_NextPart_000_0005_01C155B4.40726E80-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Tue Oct 16 13:35:52 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Tue, 16 Oct 2001 13:35:52 +0100 Subject: [AMPS] sockets Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A994@excalibur.swindon.msl.mitel.com> Rich, last week you mentioned making replacement springs from 'austenitic steel'. Just what is that? I've been through Machinery's Handbook and a whole slew of my model engineering text books, but can't find a reference to it. Incidentally, anyone wanting Ian, G3SEK will have to wait. He went into hospital last Thursday for a replacement hip: I haven't heard how he's doing yet. He expects to be in for around 10 to 12 days. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From John_Nelson@compuserve.com Tue Oct 16 20:45:28 2001 From: John_Nelson@compuserve.com (John Nelson) Date: Tue, 16 Oct 2001 15:45:28 -0400 Subject: [AMPS] Austenitic steels Message-ID: <200110161545_MC3-E37B-39AF@compuserve.com> Message text written by Peter Chadwick >Last week you mentioned making replacement springs from 'austenitic steel'. Just what is that? I've been through Machinery's Handbook and a whole slew of my model engineering text books, but can't find a reference to it.< Try 'Metals in the Service of Man' (Alexander & Street: 9th ed, Penguin 1989, pp 133 et seq) 73 John GW4FRX -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Tue Oct 16 21:18:11 2001 From: philk5pc@tyler.net (Phil Clements) Date: Tue, 16 Oct 2001 15:18:11 -0500 Subject: [AMPS] Installation of Harbach Kits Message-ID: <000f01c1567f$aedf7540$4c084c42@phil> This is a multi-part message in MIME format. ------=_NextPart_000_000C_01C15655.C5060700 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable Now that Jeff has Harbach running at full steam, I have resumed my installation service on all Harbach kits. (((73))) Phil, K5PC Phil Clements 410 VZ CR 4903 Ben Wheeler, TX 75754 ------=_NextPart_000_000C_01C15655.C5060700 Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable
Now that Jeff has Harbach running at full steam,

I have resumed my installation service on all Harbach

kits.

(((73)))

Phil, K5PC

Phil Clements
410 VZ CR 4903
Ben Wheeler, TX=20 75754
------=_NextPart_000_000C_01C15655.C5060700-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jimr.reid@verizon.net Wed Oct 17 00:19:34 2001 From: jimr.reid@verizon.net (Jim Reid) Date: Tue, 16 Oct 2001 13:19:34 -1000 Subject: [AMPS] Amp Drive Power(Long) References: <3BC362AC.26564.5EE1311@localhost> Message-ID: <003301c15699$67520ca0$a1040304@vz.dsl.genuity.net> Back in July there was a lengthy discussion here about an amp's input circuit. Now I have been finding that I have no way to really know the amp drive power from my exciter rig. I thought I did by having a VFD peak reading watt meter to set the drive, then switch that into the amp. However, W1HIS, Chuck (who has the same sort of Henry amp that I have) and I have been doing a lot of comparative tests on our amps. He has pointed out issues which impact this; I believe he is correct! His points: "1. Unless the load VSWR is exactly 1.0, the forward power indicated by any directional-coupler-wattmeter exceeds the net power delivered to the load. 2. Because the Henry amp's input is a _nonlinear_ load, for which voltage is not proportional to current!, all (simple) bets are off!! The load is nonlinear because the grid part of the cathode/grid circuit rectifies. 3. How a nonlinear load appears to a wattmeter depends strongly on the voltage and current waveforms, which are nonsinusoidal and which change depending on the length of the transmission line and any filters, tuned circuits, impedance-matching, etc., etc., between the exciter and the load (the Henry's cath/grid circuit). These nonsinusoidal waveforms have harmonic content, and the harmonic components typically are reflected from both ends of the line and form standing waves. Thus, waveshapes are different at different points on the line. Garden-variety wattmeters do not sample the entire waveforms and do not compute power, really; they use diode rectifiers, which tend to respond to peak rather than rms voltage, and so on; and they infer approximately what the power _would_ be, were only the waveforms sinusoidal." Next, Chuck ran an experiment with his Icom driven amp: "Transceiver: Icom IC-775DSP, which is all solid-state. Adjusted its output so that the VFD indicated 99 W when the Henry was bypassed. The Icom's internal antenna tuner was switched OUT. [Below I repeat the experiment with the Icom's internal antenna tuner switched IN. Whether the Icom's internal antenna tuner is switched in or out turns out to make a big difference, although it "shouldn't", because in each case the Icom was adjusted to deliver 99 W to the dummy load as indicated by the VFD.] 1.6 Indicated PA voltage....4380 or so as read on amp meter (voltage as selected using the "CW" bias position) 1.7 VFD Pout reading into Bird dummy load....1639 watts But with the Icom's internal antenna tuner switched IN and the Icom's power readjusted for 99 W to the dummy load as indicated by the VFD, then VFD Pout reading into my Bird dummy load is NOW 1896 watts! Obviously (IMO) a nonsinusoidal reflected wave, very rich in harmonics, returns from the Henry's cathode (input) circuit; and these harmonics are absorbed or reflected by the Icom completely differently depending on whether the Icom's antenna tuner is switched in. So the voltage and current waveforms delivered to the Henry are very different. 1.8 VFD indicated vswr....1.20 here, regardless of Icom tuner in/out. 1.9 Bird meter on the amp Controller Unit.......2000 watts when my VFD indicates 1896 W. 1.10 Now, lower input drive power to bring indicated output power down to 1500 watts steady CW key down....VFD reads either 1486 or 1529, evidently allowed values for the digital readout in this area. "Drive" power, VFD indicated with amp by-passed....88 Wtts." Chuck then summarizes his and my comparative measurments: "1. With the amp biased for CW, I get less or more power than you do, with the same 99 W of VFD-indicated drive power, depending on whether the antenna tuner _inside_ my exciter is switched out or in, respectively. IMO this proves that the Henry's grid circuit generates and sends a nonsinusoidal reflection back to the exciter. 2. Neither your nor my VFD indicates VSWR = 1.0 (as it should) when looking into a 50-ohm Bird termination. 3. The wattmeter on your amp controller reads higher than your VFD; my controller panel meter is also optimistic, but not by so much. 4. I always see less grid current and more plate current than you, for roughly the same RF power output. Probably nothing to worry about. Our tubes may be biased differently. 5. My filament voltage(7.4) is lower, perhaps 'cuz I changed the fil. transformer primary tap (to the top) to lower the filament voltage. Per manual, filament voltage is supposed to be 7.50 plus/minus 5%, in other words 7.125 to 7.875 ? [KH7M filament at 7.7 or so per meter on amp controller unit]. 6. My TUNE dial readings are the same as yours, but my LOAD dial readings are much higher than yours; indicates higher load C, lighter loading. 7. Both of us seem to be getting reasonable amounts of output power to the Bird loads (1600 to 1900 watts with "CW" bias and 2400-2500 W with SSB bias) with about 100 watts in. The key word being "about". 8. You might be able to get a valid measurement of the drive power required by the Henry, by using an "antenna tuner," ahead of the linear amp and inserting a drive-power meter between the exciter and said tuner. " Is there any real benefit to bringing the line between the transceiver and the amp input "flat" using either a tuner, or perhaps putting in a 3dB or so pad?? Suppose there is no real particular benefit to know the actual drive power in any case! Not sure where to obtain such a pad to handle drive powers up to 150 watts or so anyway such that half of that power is dissipated and about 70 or so "real" drive power is used. Would the output signal be cleaner with such an input tuner, or the use of a pad to bring the line flat, free of the non-linearities? Complete detailed measurement data on each of our 3CX3000A7 amps can be supplied if you might be interested. 73, Jim KH7M -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Dan" Weston RF Ammeter - Measure the RF to the antenna RF Ammeter. This is a beautiful little Weston RF Ammeter, the scale maximum is 3 Amps-works perfectly. It is mounted in a gray box, 4" square, and 2" deep (I'm not sure who mounted it but the workmanship is excellent). For auction on Ebay, click on: http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=1285346268 I will be glad to provide additional information, or send more detailed pictures to your email address. Contact me at w4tq@mindspring.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From dcoolica@planet.eon.net Wed Oct 17 06:02:05 2001 From: dcoolica@planet.eon.net (Denis Coolican) Date: Wed, 17 Oct 2001 00:02:05 -0500 Subject: [AMPS] Schematic Daiwa NS 660PA Message-ID: <3BCD10CD.458741B7@planet.eon.net> I am looking for a manual for a Daiwa Power meter NS 660PA. Is there a place to get the shematic on the net? Regards Denis Ve6AQ -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Wed Oct 17 08:00:07 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Wed, 17 Oct 2001 08:00:07 +0100 Subject: [AMPS] Austenitic steel Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A9A8@excalibur.swindon.msl.mitel.com> Thanks for all the replies. It would not appear to be the correct steel to use for springs, being too ductile. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Wed Oct 17 08:21:05 2001 From: W8JI@contesting.com (Tom Rauch) Date: Wed, 17 Oct 2001 03:21:05 -0400 Subject: [AMPS] Amp Drive Power(Long) In-Reply-To: <003301c15699$67520ca0$a1040304@vz.dsl.genuity.net> Message-ID: <3BCCF921.22794.C7A6A4C@localhost> > "1. Unless the load VSWR is exactly 1.0, the forward power > indicated by any directional-coupler-wattmeter exceeds the > net power delivered to the load. Look at the reflected power. Subtract the reflected power from forward, and you have real power delivered to the load (neglecting the small cable and input circuit losses). > 2. Because the Henry amp's input is a _nonlinear_ load, for > which voltage is not proportional to current!, all (simple) bets > are off!! The load is nonlinear because the grid part of the > cathode/grid circuit rectifies. It should not appear that non-linear ahead of the tuned input if the input has enough Q in the input and if the input is a lowpass with a low impedance for harmonics at the cathode. > 3. How a nonlinear load appears to a wattmeter depends strongly > on the voltage and current waveforms, which are nonsinusoidal > and which change depending on the length of the transmission > line and any filters, tuned circuits, impedance-matching, etc., etc., > between the exciter and the load (the Henry's cath/grid circuit). If it looks non-sinusoidal at the meter you are in serious trouble. > waveforms and do not compute power, really; they use diode rectifiers, > which tend to respond to peak rather than rms voltage, and so on; and > they infer approximately what the power _would_ be, were only the > waveforms sinusoidal." See above. Also, some of those thoughts are wrong. For example, all direction couplers I've seen at HF actually measure both current and voltage, and compare the phase. If they didn't, they could NOT be directional couplers!! > Obviously (IMO) a nonsinusoidal reflected wave, very rich in > harmonics, returns from the Henry's cathode (input) circuit; and > these harmonics are absorbed or reflected by the Icom > completely differently depending on whether the Icom's > antenna tuner is switched in. So the voltage and current > waveforms delivered to the Henry are very different. Is this a wild guess based on assumptions and unrelated measurements, or did someone actually look at the waveform on a scope?? Rest assured, if the waveform is non-sinusoidal the rig and the meter will show standing waves. Of course the very same thing can happen if there are no harmonics and there actually IS only an impedance mismatch. The only way you would know is to look at the waveform, or measure the level of harmonics. > "1. With the amp biased for CW, I get less or more power than > you do, with the same 99 W of VFD-indicated drive power, > depending on whether the antenna tuner _inside_ my exciter is > switched out or in, respectively. IMO this proves that the Henry's > grid circuit generates and sends a nonsinusoidal reflection back to > the exciter. Doesn't **prove** that at all! You need to measure the harmonics, or look at it with a scope. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From mike.tubby@thorcom.co.uk Wed Oct 17 12:28:05 2001 From: mike.tubby@thorcom.co.uk (Michael J. Tubby B.Sc. (Hons) G8TIC) Date: Wed, 17 Oct 2001 12:28:05 +0100 Subject: [AMPS] Amp Drive Power(Long) References: <3BC362AC.26564.5EE1311@localhost> <003301c15699$67520ca0$a1040304@vz.dsl.genuity.net> Message-ID: <002101c156fe$ca390160$7001a8c0@int.thorcom.com> ----- Original Message ----- From: "Jim Reid" To: "AMPS" Sent: Wednesday, October 17, 2001 12:19 AM Subject: [AMPS] Amp Drive Power(Long) > > Back in July there was a lengthy discussion here about > an amp's input circuit. Now I have been finding that > I have no way to really know the amp drive power from > my exciter rig. I thought I did by having a VFD peak reading > watt meter to set the drive, then switch that into the amp. > > However, W1HIS, Chuck (who has the same sort of Henry > amp that I have) and I have been doing a lot of comparative > tests on our amps. He has pointed out issues which > impact this; I believe he is correct! His points: > > "1. Unless the load VSWR is exactly 1.0, the forward power > indicated by any directional-coupler-wattmeter exceeds the > net power delivered to the load. > > 2. Because the Henry amp's input is a _nonlinear_ load, for > which voltage is not proportional to current!, all (simple) bets > are off!! The load is nonlinear because the grid part of the > cathode/grid circuit rectifies. > > 3. How a nonlinear load appears to a wattmeter depends strongly > on the voltage and current waveforms, which are nonsinusoidal > and which change depending on the length of the transmission > line and any filters, tuned circuits, impedance-matching, etc., etc., > between the exciter and the load (the Henry's cath/grid circuit). These > nonsinusoidal waveforms have harmonic content, and the harmonic components > typically are reflected from both ends of the line and > form standing waves. Thus, waveshapes are different at different > points on the line. Garden-variety wattmeters do not sample the > entire waveforms and do not compute power, really; they use > diode rectifiers, which tend to respond to peak rather than rms > voltage, and so on; and they infer approximately what the > power _would_ be, were only the waveforms sinusoidal." > > Next, Chuck ran an experiment with his Icom driven amp: > > "Transceiver: Icom IC-775DSP, which is all solid-state. Adjusted > its output so that the VFD indicated 99 W when the Henry was > bypassed. The Icom's internal antenna tuner was switched OUT. > > [Below I repeat the experiment with the Icom's internal > antenna tuner switched IN. Whether the Icom's internal antenna > tuner is switched in or out turns out to make a big difference, > although it "shouldn't", because in each case the Icom was > adjusted to deliver 99 W to the dummy load as indicated by the > VFD.] > > 1.6 Indicated PA voltage....4380 or so as read on > amp meter (voltage as selected using the "CW" bias position) > > 1.7 VFD Pout reading into Bird dummy load....1639 watts > > But with the Icom's internal antenna tuner switched IN and the > Icom's power readjusted for 99 W to the dummy load as > indicated by the VFD, then VFD Pout reading into my Bird dummy > load is NOW 1896 watts! > > Obviously (IMO) a nonsinusoidal reflected wave, very rich in > harmonics, returns from the Henry's cathode (input) circuit; and > these harmonics are absorbed or reflected by the Icom > completely differently depending on whether the Icom's > antenna tuner is switched in. So the voltage and current > waveforms delivered to the Henry are very different. > > 1.8 VFD indicated vswr....1.20 here, regardless of Icom > tuner in/out. > > 1.9 Bird meter on the amp Controller Unit.......2000 watts > when my VFD indicates 1896 W. > > 1.10 Now, lower input drive power to bring indicated output > power down to 1500 watts steady CW key down....VFD reads > either 1486 or 1529, evidently allowed values > for the digital readout in this area. > > "Drive" power, VFD indicated with amp by-passed....88 Wtts." > > Chuck then summarizes his and my comparative measurments: > > "1. With the amp biased for CW, I get less or more power than > you do, with the same 99 W of VFD-indicated drive power, > depending on whether the antenna tuner _inside_ my exciter is > switched out or in, respectively. IMO this proves that the Henry's > grid circuit generates and sends a nonsinusoidal reflection back > to the exciter. > > 2. Neither your nor my VFD indicates VSWR = 1.0 (as it should) > when looking into a 50-ohm Bird termination. > > 3. The wattmeter on your amp controller reads higher than your > VFD; my controller panel meter is also optimistic, but not by > so much. > > 4. I always see less grid current and more plate current than you, > for roughly the same RF power output. Probably nothing to worry > about. Our tubes may be biased differently. > > 5. My filament voltage(7.4) is lower, perhaps 'cuz I changed the fil. > transformer primary tap (to the top) to lower the filament voltage. > Per manual, filament voltage is supposed to be 7.50 plus/minus > 5%, in other words 7.125 to 7.875 ? [KH7M filament at 7.7 or so > per meter on amp controller unit]. > > 6. My TUNE dial readings are the same as yours, but my LOAD > dial readings are much higher than yours; indicates higher load > C, lighter loading. > > 7. Both of us seem to be getting reasonable amounts of output > power to the Bird loads (1600 to 1900 watts with "CW" bias and > 2400-2500 W with SSB bias) with about 100 watts in. The key > word being "about". > > 8. You might be able to get a valid measurement of the drive > power required by the Henry, by using an "antenna tuner," > ahead of the linear amp and inserting a drive-power meter > between the exciter and said tuner. " > > Is there any real benefit to bringing the line between the > transceiver and the amp input "flat" using either a tuner, > or perhaps putting in a 3dB or so pad?? Suppose there is > no real particular benefit to know the actual drive power > in any case! Not sure where to obtain such a pad to > handle drive powers up to 150 watts or so anyway such > that half of that power is dissipated and about 70 or so > "real" drive power is used. Would the output signal be > cleaner with such an input tuner, or the use of a pad > to bring the line flat, free of the non-linearities? > > Complete detailed measurement data on each of our > 3CX3000A7 amps can be supplied if you might be > interested. > > 73, Jim KH7M > > Interesting tests but do you beleive the output of the Icom 775 to be 50R+0j without the tuner... bet it isn't and therefore you are actually looking at the complex network of: - output of radio - length of 50R (ish) coax - input to Henry - change of impedance over drive cycle Can you do the same tests at 1/4 power and get the same (relative) results? Probably not because the "aparrent" impedance of the input of the Henry will change as will the "aparrent" output of the radio. If you can get some more-or-less comparative results - like basically you see the same behaviour when switching the tuner in/out then it should be interesting to see what happens with a 6dB 100W rated attenuator (a) at the back of the rig, and (b) at the input to the amp. Its precisely these sort of things which cause me to prefer Tetrode amps which are grid driven (esp. at VHF) - even then I like a 6dB pad on the input of the amp. For your amp you might like to try a 1/2-wave length of coax between rig and radio on the band of interest [test] (taking velocity factor into account) to eliminate the "transform effect" of the coax from the equation. Mike G8TIC/M0VHF > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From sanil@sancharnet.in Tue Oct 16 23:51:37 2001 From: sanil@sancharnet.in (Anil) Date: Wed, 17 Oct 2001 04:21:37 +0530 Subject: [AMPS] Help References: <004f01c15699$b87a6aa0$817645cf@computer> Message-ID: <000101c15699$e75e8180$3131003d@k0a4u6> Hello, I have a linear amplifier pate used in Marine HF solid state linear which used 4 such plate and hybrid combiner and giving 1.6kw power output. I've one plate only using two RF transistors SRFE-1058 in push pull and can give approx. 400W output. I've no schematic of this plate and no details about such RF transistors. I need:-- 1. schematic of the plate 2. data of the RF transistors SRFE-1058 3. Powersupply details about such plate. 4. Biasing details. 4. How to connect Solid state TXRX to this plate to give input ? 5. Bandpass filter in the output. 6. relay connection to the antenna I request please give me details and suggest me any website and other source for details. Regards. Anil VU2TRI -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From c.jogenborn@telia.com Wed Oct 17 06:27:39 2001 From: c.jogenborn@telia.com (Christer Jogenborn) Date: Wed, 17 Oct 2001 07:27:39 +0200 Subject: [AMPS] Q: Eimac 290A Message-ID: <005d01c156cc$7097d3c0$b195c6c3@a010039409> This is a multi-part message in MIME format. ------=_NextPart_000_005A_01C156DD.334F9820 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Looking for tech.specifcations on the 290A Eimac tube I would expect that data can be similar as for the nCX5000 types It sits in a SK-291A socket. /Chris SM0NCL ------=_NextPart_000_005A_01C156DD.334F9820 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Looking for tech.specifcations on = the 290A Eimac=20 tube

I would expect that data can be = similar as for=20 the nCX5000 types

It sits in a = SK-291A=20 socket.

/Chris SM0NCL

------=_NextPart_000_005A_01C156DD.334F9820-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Wed Oct 17 14:33:51 2001 From: W8JI@contesting.com (Tom Rauch) Date: Wed, 17 Oct 2001 09:33:51 -0400 Subject: [AMPS] Amp Drive Power(Long) In-Reply-To: <002101c156fe$ca390160$7001a8c0@int.thorcom.com> Message-ID: <3BCD507F.32227.DCFC005@localhost> > - change of impedance over drive cycle The best way to look at this is with harmonic content required to make a wave some shape other than a sine wave. The waveform MUST have harmonics of the drive frequency to change waveshape during a fraction of an RF cycle, because the required frequencies to modify the sine wave in such a small time interval are at least two times the drive frequency. If there is significant attenuation of signals at two times the drive frequency, you can be absolutely sure anything happening at the cathode is unimportant What confuses people is they look at the change in drive impedance with drive level and assume this affects the fractional RF-cycle impedance. It does not, if the input has almost any Q at all and is a low pass network. > Its precisely these sort of things which cause me to prefer Tetrode > amps which are grid driven (esp. at VHF) - even then I like a 6dB pad > on the input of the amp. Because of the lack of inherent negative feedback, many practical tetrode amplifiers are not nearly as clean as a cathode driven system. The high amount of feedback also moderates the SWR. For example the input SWR on my AL1200 is 1.15 : 1 at 1 watt and only changes to 1.00 at 200 watts of RF drive. What may confuse people is if you vary the loading control or plate tuning, the input SWR changes a noticeable amount. This is especially true in higher gain cathode driven stages. It was a bit of advertising fluff by a tetrode marketing department that mostly touted the "tetrode" advantage. That was ironic, since at the same time the same marketing people thought grids could be largely unregulated based on over-the-air "am I splattering much Herbie?" measurements. IMD measurements show how dirty most tetrode amps commonly used actually are. > For your amp you might like to try a 1/2-wave length of coax between > rig and radio on the band of interest [test] (taking velocity factor > into account) to eliminate the "transform effect" of the coax from the > equation. Having a certain length of cable in fractions of a wavelength guarantees nothing, except how far away the PA can be physically placed. Just make sure the amplifier is matched to the cable impedance. The normal range of 50 ohm cables I have measured is 45-55 ohms. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Mike" Hi All, We have 3 Ameritron AL-82's at our local club station. The station was recently moved into a new shack which is wired with one phase of a 3 phase 208 VAC service (the old shack was setup for 240 VAC). Some of the guys were a little worried about setting the transformer taps on the AL-82s all the way down 208VAC, instead suggesting that we go with the 220V taps just to be conservative. I was concerned that this might drop the filament voltage a bit too much to achieve full emission. Any reason not to run on the 208VAC taps. I am told that this is a true 208 VAC drop, and not just a 220V drop running on the low side of the voltage tolerance, so I see no reason not to run on the 82's 208 VAC taps? Thanks, Mike, W4EF........... -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 17 15:16:44 2001 From: 2@vc.net (2) Date: Wed, 17 Oct 2001 07:16:44 -0700 Subject: [AMPS] Amp Drive Power(Long) Message-ID: <200110171416.f9HEGDZ04892@contesting.com> > >> "1. Unless the load VSWR is exactly 1.0, the forward power >> indicated by any directional-coupler-wattmeter exceeds the >> net power delivered to the load. > >Look at the reflected power. Subtract the reflected power from >forward, and you have real power delivered to the load (neglecting >the small cable and input circuit losses). > // Yet another popular belief in ham radioland. Proving or disprooving the "real power" utterance requires a dual-trace 'scope, a calculator, a DMM, a not-50-ohm termination, and an unclosed mind. My guess is that it's not quite as simple as A minus B. "Nothing is as simple as it looks." -- Murphy The list: 1. Electromagnetic radiation comes from the high-current part of an antenna. 2. Adding tubes in parallel reduces the possibility of making an amplifier work on 10m. 3. A 40% increase in power makes one kick-butt stronger in HF pileups. 4. An arc in a near-vacuum make a loud bang. 5. 6000VDC is more dangerous to humanoids than 120VAC. 6. You have to hear 'em to work 'em. 7. Virtually all tube failures are caused by tube manufacturering defects or schmuck-operator errors. 8. Ferrite core manufacturers' frequency ratings can be ignored for balun service. 9. It's possible to have a good Field Day without a supply of brewskis. > ... ... >> ... >> "1. With the amp biased for CW, I get less or more power than >> you do, with the same 99 W of VFD-indicated drive power, >> depending on whether the antenna tuner _inside_ my exciter is >> switched out or in, respectively. IMO this proves that the Henry's >> grid circuit generates and sends a nonsinusoidal reflection back to >> the exciter. > >Doesn't **prove** that at all! You need to measure the harmonics, >or look at it with a scope. > // Yea, verily, Mr. Rauch. - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Wed Oct 17 15:26:16 2001 From: stevek@jmr.com (Steve Katz) Date: Wed, 17 Oct 2001 07:26:16 -0700 Subject: [AMPS] AL-82 Primary Tap Settings Message-ID: Why not hook it up that way, and use a good AC voltmeter to measure the filament voltage at one of the tube sockets? Is the xfmr in the AL-82 common to both HV and filament (as it is in the AL-80B)? If so, the issue is somewhat muddied; I tapped my AL-80B on the 240V tap because my RMS line voltage actually measures 242V, but that led to both HV and fil V being a bit lower than recommended, so I had to re-open (27 screws!) the cabinet and re-tap for 220V, now all is well. WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Mike [SMTP:W4EF@dellroy.com] > Sent: Wednesday, October 17, 2001 6:44 AM > To: AMPS > Subject: [AMPS] AL-82 Primary Tap Settings > > > Hi All, > > We have 3 Ameritron AL-82's at our local club station. The station was > recently > moved into a new shack which is wired with one phase of a 3 phase 208 VAC > service > (the old shack was setup for 240 VAC). Some of the guys were a little > worried > about setting the transformer taps on the AL-82s all the way down 208VAC, > instead > suggesting that we go with the 220V taps just to be conservative. I was > concerned that > this might drop the filament voltage a bit too much to achieve full > emission. Any > reason not to run on the 208VAC taps. I am told that this is a true 208 > VAC drop, and > not just a 220V drop running on the low side of the voltage tolerance, so > I see no > reason not to run on the 82's 208 VAC taps? > > Thanks, > > Mike, W4EF........... > > > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Wed Oct 17 15:42:55 2001 From: philk5pc@tyler.net (Phil Clements) Date: Wed, 17 Oct 2001 09:42:55 -0500 Subject: [AMPS] AL-82 Primary Tap Settings References: <007801c15711$cd8831c0$6401a8c0@neptune> Message-ID: <001b01c1571a$034c9000$87084c42@phil> The only way to properly set the transformer taps is to measure the filament voltage at the tube pins at each setting. I would start with the 220 volt tap first. If the voltage is within specs, you are there! Try to borrow a good voltmeter if you don't own one. (((73))) Phil, K5PC > > We have 3 Ameritron AL-82's at our local club station. The station was recently > moved into a new shack which is wired with one phase of a 3 phase 208 VAC service > (the old shack was setup for 240 VAC). Some of the guys were a little worried > about setting the transformer taps on the AL-82s all the way down 208VAC, instead > suggesting that we go with the 220V taps just to be conservative. I was concerned that > this might drop the filament voltage a bit too much to achieve full emission. Any > reason not to run on the 208VAC taps. I am told that this is a true 208 VAC drop, and > not just a 220V drop running on the low side of the voltage tolerance, so I see no > reason not to run on the 82's 208 VAC taps? -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 17 16:27:38 2001 From: 2@vc.net (2) Date: Wed, 17 Oct 2001 08:27:38 -0700 Subject: [AMPS] Austenitic steel Message-ID: <200110171527.f9HFR5Z06913@contesting.com> > >Thanks for all the replies. It would not appear to be the correct steel to >use for springs, being too ductile. > // I am trying to find out more about this. However, as in beer, there are different brews of austenitic steel. My guess is that some types have a temper-memory, and do not require tempering after being heated and bent. The type of "piano wire" sold in model aeroplane shops can be heated to orange-heat and bent -sans-re-tempering -without loosing its springiness. > cheers, Peter - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 17 16:27:39 2001 From: 2@vc.net (2) Date: Wed, 17 Oct 2001 08:27:39 -0700 Subject: [AMPS] Q: Eimac 290A Message-ID: <200110171527.f9HFR6Z06917@contesting.com> >Looking for tech.specifcations on the 290A Eimac tube >I would expect that data can be similar as for the nCX5000 types >It sits in a SK-291A socket. > // The 290 is a Class AB1 pentode with an oxide-cathode and a delicate 2w grid. The heater needs 17A at 5.7 - 6.3 volts. Anode ratings for A� are 6000V, 2A. For SSB, 7000V should be ok. To get 2a, the screen-potential needs to be c. 900v. Since the 290's screen is subject to reverse-current, a zener string shunt regulator would be good. Zener current needs to be c. 65mA. To protect the delicate screen from over-current, the zener string should fed from a power resistor connected to a 3000v or more source. I would use a string of 24v - 30v, 5w zeners mounted on perforated board, near the cooling airflow. [note - "5w-rated" zeners should not be operated above 2w without liquid cooling]. With a 150w transceiver, the needed 120V-peak RF grid voltage can be achieved with a 50-ohm grid termination. My guess is that 9k-out PEP should be possible on SSB. Back off the mic. gain until the anode-I doesn't modulate (a.k.a. Class A) and you should have around 1k out. . . "Speak softly and carry a big stick." cheers, Chris - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 17 16:27:41 2001 From: 2@vc.net (2) Date: Wed, 17 Oct 2001 08:27:41 -0700 Subject: [AMPS] AL-82 Primary Tap Settings Message-ID: <200110171527.f9HFR8Z06921@contesting.com> > >Hi All, > >We have 3 Ameritron AL-82's at our local club station. The station was >recently >moved into a new shack which is wired with one phase of a 3 phase 208 VAC >service >(the old shack was setup for 240 VAC). Some of the guys were a little >worried >about setting the transformer taps on the AL-82s all the way down 208VAC, >instead >suggesting that we go with the 220V taps just to be conservative. I was >concerned that >this might drop the filament voltage a bit too much to achieve full >emission. Any >reason not to run on the 208VAC taps. I am told that this is a true 208 >VAC drop, and >not just a 220V drop running on the low side of the voltage tolerance, so >I see no >reason not to run on the 82's 208 VAC taps? > // Low-hours 3-500Zs need around 4.7v minimum on the filament. - You might be interested in: Figure 17 on my Web site (arced bandswitch removed from a MFJ-Ameritron AL-82 amplifier). > cheers, Mike - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 17 16:27:42 2001 From: 2@vc.net (2) Date: Wed, 17 Oct 2001 08:27:42 -0700 Subject: [AMPS] Amp Drive Power(Long) Message-ID: <200110171527.f9HFRAZ06928@contesting.com> > >> - change of impedance over drive cycle > >The best way to look at this is with harmonic content required to >make a wave some shape other than a sine wave. The waveform >MUST have harmonics of the drive frequency to change waveshape >during a fraction of an RF cycle, because the required frequencies >to modify the sine wave in such a small time interval are at least >two times the drive frequency. > // say what? - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Wed Oct 17 16:23:22 2001 From: stevek@jmr.com (Steve Katz) Date: Wed, 17 Oct 2001 08:23:22 -0700 Subject: [AMPS] AL-82 Primary Tap Settings Message-ID: AC measurement is certainly a bit tricky. I use an old Ballantine Labs AC VTVM from the 1950's, seems to be the only think I own that has any accuracy on the AC range.... WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Phil Clements [SMTP:philk5pc@tyler.net] > Sent: Wednesday, October 17, 2001 7:43 AM > To: Mike; AMPS > Subject: Re: [AMPS] AL-82 Primary Tap Settings > > > The only way to properly set the transformer taps is to > measure the filament voltage at the tube pins at each > setting. I would start with the 220 volt tap first. If the voltage > is within specs, you are there! > > Try to borrow a good voltmeter if you don't own one. > (((73))) > Phil, K5PC > > > > We have 3 Ameritron AL-82's at our local club station. The station was > recently > > moved into a new shack which is wired with one phase of a 3 phase 208 > VAC > service > > (the old shack was setup for 240 VAC). Some of the guys were a little > worried > > about setting the transformer taps on the AL-82s all the way down > 208VAC, > instead > > suggesting that we go with the 220V taps just to be conservative. I was > concerned that > > this might drop the filament voltage a bit too much to achieve full > emission. > Any > > reason not to run on the 208VAC taps. I am told that this is a true 208 > VAC > drop, and > > not just a 220V drop running on the low side of the voltage tolerance, > so I > see no > > reason not to run on the 82's 208 VAC taps? > > > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 17 16:37:27 2001 From: 2@vc.net (2) Date: Wed, 17 Oct 2001 08:37:27 -0700 Subject: [AMPS] AL-82 Primary Tap Settings Message-ID: <200110171536.f9HFatZ07557@contesting.com> > >The only way to properly set the transformer taps is to >measure the filament voltage at the tube pins at each >setting. // Amen, Phil > I would start with the 220 volt tap first. If the voltage >is within specs, you are there! // However, operating a 5v +/- 5% filament at 5.25v instead of 4.75v will reduce emissive life to [4.75v/5.25v] ^23.4 = c. 1/10 of normal life. > >... - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w5ben@arrl.net Wed Oct 17 17:05:22 2001 From: w5ben@arrl.net (Duane Budd) Date: Wed, 17 Oct 2001 12:05:22 -0400 Subject: [AMPS] RF Ammeter - Weston - Ebay Auction In-Reply-To: <004f01c15699$b87a6aa0$817645cf@computer> Message-ID: I thought we were not supposed to reference auction sites on the reflector. Not right? Duane Budd w5ben@arrl.net -----Original Message----- From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On Behalf Of Dan Sent: Tuesday, October 16, 2001 19:25 PM To: Amps List Subject: [AMPS] RF Ammeter - Weston - Ebay Auction Weston RF Ammeter - Measure the RF to the antenna RF Ammeter. This is a beautiful little Weston RF Ammeter, the scale maximum is 3 Amps-works perfectly. It is mounted in a gray box, 4" square, and 2" deep (I'm not sure who mounted it but the workmanship is excellent). For auction on Ebay, click on: http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=12853 46268 I will be glad to provide additional information, or send more detailed pictures to your email address. Contact me at w4tq@mindspring.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 17 17:25:14 2001 From: 2@vc.net (2) Date: Wed, 17 Oct 2001 09:25:14 -0700 Subject: [AMPS] AL-82 Primary Tap Settings Message-ID: <200110171624.f9HGOfZ08981@contesting.com> > >AC measurement is certainly a bit tricky. I use an old Ballantine Labs AC >VTVM from the 1950's, seems to be the only think I own that has any accuracy >on the AC range.... > // I used to calibrate and repair John Fluke DMMs. They are typically better than the spec on AC V. >... - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jsschuster@snet.net Thu Oct 18 05:16:06 2001 From: jsschuster@snet.net (jsschuster) Date: Thu, 18 Oct 2001 00:16:06 -0400 Subject: [AMPS] Alpha question I will be operating at a station with two Alpha 87A's , and the owner says there is a problem if both amps are on 10, 15, or 20 (not on the same band). The reflected power goes up and the amp shuts down when the second amp is transmitting. I am thinking of using a single stub on each. If "A" is on 15, and "B" is on 10, Ill put a qurter wave open stub for 10 on "A", and a similar one for 15 on the output of "B". Has anyone experienced this with 87A's, and do you think a single stub will do it as described? Sorry if this has been discussed before. Tnx JACK W1WEF (Antennas are three F12 tribanders on one tower spaced at least 30 ft...each rig has a Dunestar 600) -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Thu Oct 18 02:23:24 2001 From: W8JI@contesting.com (Tom Rauch) Date: Wed, 17 Oct 2001 21:23:24 -0400 Subject: [AMPS] Amp Drive Power(Long) In-Reply-To: <003301c1576d$7ac0ec00$0290a8c0@jp> Message-ID: <3BCDF6CC.27239.1057DF63@localhost> > There are very good amplifier designs that exhibit no positive (thank > god) or negative feedback and which are more-or-less the equivalent of > "open loop" (in op-amp terms), like the 1990 ARRL design with a > 4CX1000A on 144 (the onr which runs the screen at RF/DC ground and > cathode below). Is it grid driven? > Correct me but... a 1/2-wave length of coax at the test/operating > frequency in question between the amplifier and radio will present the > 'real' Zi of the amplifier to the radio and the 'real' Zo of the radio > to the amplifier, ie. the coax and any transform that it was > contributing to the test will vanish. Sure that is true, but it is obviously not the concern Jim has...unless he is using 75 ohm cable between a 50 ohm amp and his exciter. > Its easy to say "just make sure the amp is matched..." but afterall > that was the point of the experiments he was doing... my point was > that just as in the real world the amp doesn't have an input Z of > 50R+0j nor does the radio's output have a source impedance of 50R+0j The radio's output impedance has nothing to do with SWR readings on the line, although I agree many solid state radios "like" load impedances other than exactly 50 ohms. > Have you ever 'looked into' the output impedance of a radio > transceiver with something like a Wiltron Network Analyser - > sure isn't 50R+0j, hence the whole 'problem' (if indeeded it is > one) is a mixture of tuning amp input versus radio output - and > the two interact. You can not look into the PA and get a meaningful reading, unless it is on. You have to do a load pull, or use a reverse source that is unaffected by transmitter power. > Placing a 1/2-wave coax between the two simply eliminates one > factor, making it easier to workout what the interaction is. Eliminating the most predicable and easiest measured item in the system isn't necessarily a major advantage. > In the smaller station at home I use an FT847 with a Commander-II > 3CX800, it has 'strange' modes of tune-up - the input circuit > interacting with the FT847 and length of coax between the two. For > some coax lengths I 'appear' to need > 30W drive for full output while > other lengths I need only about 18W for the same output. What's > intersting is the difference in grid current and aparrent efficiency > of the amplifier. Must have a poor input circuit. What type is it? Is it a low pass or bandpass with enough Q, and one that provides a low impedance at the cathode for harmonics of the drive frequency?? 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Mike" Message-ID: <00f601c15789$3965e640$6401a8c0@neptune> Hi Jack, A single 1/4 wave stub made from low-loss coax will give you between 20 and 25 dB of attenuation when properly adjusted. If the second station doesn't shut down the amp on the first station when the second station is only running barefoot, then a single stub should be more than good enough when running the amp on the second station. The filtering scenario you describe needs to be modified slightly to work properly. A open 1/4 wave stub cut for ten meters will look like a 3/16 wave open stub 15 meters. This will look like a shunt capacitor and will wreak havoc with your 15 meter SWR. Use a 3/4 wavelength shorted stub across the amplifier output when you are operating 15 meters (this will look like a 1/2 wave and a one wavelength shorted stub on 20 and 10 meters respectively). When operating twenty meters, use a open 1/2 wavelength stub on the amplifier output to kill 15 and a shorted 1/4 wavelength stub to kill 10 (you can put them in parallel to kill both 10 and 15 simultaneously). Finally when running ten meters, an open 1 wavelength stub will kill 15 and a shorted 1/4 wave stub will kill 20. Since the 3/4 wavelength 15 meter stub will be the same length as the 1 wavelength 10 meter stub, I have summarized everything below in terms of wavelenghts measured at 10 meters to give you an idea of how one stub can be reused for several different combination of bands (remember I am referring to electrical length so you need to account for the velocity factor of the coax you are using when sizing the stubs): XMT BAND 10 1 WL OPEN (Kills 15, Passes 10/20) 1/2 WL OPEN (Kills 20, Passes 10) 15 1 WL SHORTED (Kills 10/20, Passes 15) 20 1 WL OPEN (Kills 15, Passes 10/20) 1/2 WL SHORTED (Kills 10, Passes 20) Note: stub lengths are expressed in terms of wavelengths on 10 meters. As you can see, if you have a switch that allows you to change from an open to a short on the stub termination, then you really only need a single pair of stubs one each station to handle all of the possible combinations. BTW, I have had excellent results using LMR-400 for stubs. Good Luck, Mike, W4EF.......... ----- Original Message ----- From: "jsschuster" To: Sent: Wednesday, October 17, 2001 9:16 PM Subject: [AMPS] Alpha question > > I will be operating at a station with two Alpha 87A's , and the owner > says there is a problem if both amps are on 10, 15, or 20 (not on the > same band). The reflected power goes up and the amp shuts down when the > second amp is transmitting. I am thinking of using a single stub on > each. If "A" is on 15, and "B" is on 10, Ill put a qurter wave open stub > for 10 on "A", and a similar one for 15 on the output of "B". > Has anyone experienced this with 87A's, and do you think a single stub > will do it as described? Sorry if this has been discussed before. Tnx > JACK W1WEF > (Antennas are three F12 tribanders on one tower spaced at least 30 > ft...each rig has a Dunestar 600) > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Thu Oct 18 07:50:48 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Thu, 18 Oct 2001 07:50:48 +0100 Subject: [AMPS] G3SEK Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A9B6@excalibur.swindon.msl.mitel.com> Ian is doing well, and should be out of hospital on Sunday. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Thu Oct 18 08:12:14 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Thu, 18 Oct 2001 08:12:14 +0100 Subject: [AMPS] Austenitic steel Austenite is an unstable (below about 1330 deg F) solution of carbon in iron. The addition of various elements such as chromium and nickel make it stable at lower temperatures, so 'austenitic' steel is of necessity a 'stainless' steel. Because of its ductility, I doubt it makes good springs. 'Piano wire' is a high carbon steel: the usual heat treatment there is that to remove springiness, it needs annealing. So you might lose a bit of springiness by heating to red heat and bending, but probably not too much if you're fairly quick. Heat treatment is usually recommended as a 'soaking' at red heat or whatever for 1 hour per inch thickness of material; annealing requires very slow cooling. For any particular steel, see manufacturers recommendations. Some authorities recommend quenching in brine rather than water for a harder result, but I've never found an observable difference. Some steels are oil quenched. A good source of material for shaft extensions if you want steel is 'silver steel', known in the US as 'drill rod'. Not cheap, but accurate in size. However, I've found 1/4 inch diameter brass rod available quite cheaply at Home Depot stores in California. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Thu Oct 18 15:05:21 2001 From: 2@vc.net (2) Date: Thu, 18 Oct 2001 07:05:21 -0700 Subject: [AMPS] Re: 8k ultra/ "tuned input" Message-ID: <200110181404.f9IE4lZ29345@contesting.com> >gents > >Per my henry 8-K ultra manual, (I collect manuals), the "tuned >input" consists of 2 un-uns back to back. They step the Z up >with a 1:56 to 1 un-un and then back down again, same ratio >in reverse, on all bands except 10m, on 10m they step up with >one ratio, and down with a different ratio. (un-uns are relay >switched) > > How they get any fly wheel effect at all is beyond me. // They don't. Tuned circuits act as flywheels. Untuned/broadband transformers have virtually no flywheel effect. - Back in the days when Henry Radio did not build a 160m amplifier, a friend dropped by the Henry Radio booth at a ham convention. He asked a Henry engineer why they did not build a 3-500Z 160m amplifier. The Henry engineer said that they tried it, but they discovered that 3-500Zs have a cutoff frequency that's above 2MHz, so they don't work efficiently on the 160m band. (sic) >This broad band input is a Henry exclusive used on the 8k ultra and >3-k ultra. > // "Exclusive". Chortle. No tuned-input on a g-g amplifier is Looneytunes. >The 8k manual also warns not to use the automatic tuner built >into many rigs. It sez to leave the auto tuner offline, and >just put up with any swr between xcvr and 8k ultra input. > // The trouble with auto-tuners that are built into radios (except the TS-930S) is they run c. 1w during the autotune cycle. The sticky wicket is that - unlike antennas - g-g amplifiers have a different input Z at 1w than they have with high drive power. Thus, whan the tuner is adjusted at 1w to a g-g amplifier, the SWR is sure to be feculent at 100w or so. >I noticed on my homebrew 3CX-3000A7, with it's high C low L >tuned input (consisting of a tapped 4 uh coil made from solid >5/32" copper wire, and 2 x 4 section broadcast variables (padded >on 160m), and with a network Q of abt 3.5, it works just >fine. // 'Tis indeed misfortunate that you don't design Henry Radio's g-g amplifiers. > >However, when using a wattmeter like a drake W4 inserted between >FT-1000D and input to amp, minimum swr on W4 wattmeter does not >coincide with minimum swr on FT-1000D internal swr meter. I can >tweak tuned input to read flat swr on either wattmeter, but >can't get minimum on both at same time. > >I then replaced W4 wattmeter with my Bird -43, and now flat swr >is indicated on both 43 and internal yaesu swr meter, >regardless of length of coax cables between rig and wattmeter, and >wattmeter to input to amp. Also maximum grid current >coincides with minimum reflected power between xcvr and amp. > >The VFD wattmeter may be at fault. The henry "input" with it's >back to back un-uns (all relay switched) may be creating some >problems. > >-henry doesn't change the bias on cw/ssb. The bias consists of >15-20 diodes in series in one block like a W2AW module. The >idle current zsac goes up and down cuz of plate V difference >between SSB V and lower cw V. Manual sez no load HV on ssb >should be 5400V . Henry uses a 6kv plate xfmr with a choke >input..... .9 x 6000= 5400V. They also suck a continuous >300W of bleeder power all the time to make the tuned choke, >look like a choke. // A friend bought a 60-Hz custom tuned-choke L/C matched pair from Peter W. Dahl. The amount of bleeder current needed was much less than expected. > If any of the 5 x 100 watt bleeders ever >opened up, the HV would skyrocket to 8485V. And that's if you >have the correct tap to start with. > // However, the filter capacitor could probably take the surge. When the amplifier was keyed, the ZSAC acts as a bleeder current. > The fil V should be below 7.5 V measured right at the >socket. Life of tube is dependent on fil V. If the tube is >lit, the clock is ticking. The tube won't last any longer cuz >you are running it at 1500w out. If you had a 2nd amp. with >just the tube fil lit, and no drive applied, and no HV, it >would last just as long as your driven amp. // Excellent points, Jim. Few designers seem to realize that the emissive life of a thoriated-tungsten cathode/filament is cut in Half for each 3% increase in filament voltage above what is needed to achieve full PEP. Thus, the formula for emissive life vs fil. volts = (e1/e2)^23.4. > >The stock blower on the 8K ultra will not provide enough air >for anywhere near 4kw of anode diss, more like 2500w tops. The >stock straight up and down chimney puts quite a restriction on >the airflow. // A high-pressure blower from Kooltronics or Rotron would cure this problem. Henry engineering is apparently clueless about manometers and the effect of filament potential. > >The henry back to back un-uns are interesting though I don't >understand the theory behind them. They operate from 1.8-30mhz >continuous. // But the SWR is somewhat less than satisfactory. > cheers, Jim - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From doug@nc.rr.com Thu Oct 18 16:03:56 2001 From: doug@nc.rr.com (Doug Hall) Date: Thu, 18 Oct 2001 11:03:56 -0400 Subject: [AMPS] Re: 8k ultra/ "tuned input" In-Reply-To: <200110181404.f9IE4lZ29345@contesting.com> Message-ID: Rich wrote: > - Back in the days when Henry Radio did not build a 160m amplifier, a > friend dropped by the Henry Radio booth at a ham convention. He asked a > Henry engineer why they did not build a 3-500Z 160m amplifier. The Henry > engineer said that they tried it, but they discovered that 3-500Zs have a > cutoff frequency that's above 2MHz, so they don't work efficiently on the > 160m band. (sic) Rich, What was the name of the engineer who made this statement? Was he actually an engineer or just a sales guy doing booth duty? Doug, K4DSP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Thu Oct 18 16:35:32 2001 From: stevek@jmr.com (Steve Katz) Date: Thu, 18 Oct 2001 08:35:32 -0700 Subject: [AMPS] Re: 8k ultra/ "tuned input" Message-ID: Sounds like 10 lbs of tripe. Or, knowing Henry Radio, possibly 190 lbs. The first amateur amp Henry ever built to cover 160m was the 3K Classic Mk III using a single 3CX1200D7, in ~1986. I had to bully them into it, by working with Ted S. (Shannon) Henry and giving him a cash-up-front order for 12 amplifiers. Ted told me they never added 160m to their amps because of physical limitations, and how the enclosure would detune circuitry and they'd never accomplish a reasonable Q, blah blah. I had already built a 4-1000A for 160 years earlier, on a much smaller chassis than the 3K, and it had no problem delivering 1750W output with about 60% efficiency; I provided Ted with the details of my circuit, which were largely lifted from an old Radio Handbook. The amps were finally delivered about 4 months later, and the 160m bandswitch position had been added, along with a huge piece of B&W stock, padder caps (doorknobs) all over, a 160m tuned input, etc. The resultant Q seemed reasonable, based on the half-power BW of the output tank...tuned broadly and easily, and one setting would cover about 30 kHz on 1.8 MHz, not bad. The _problems_ with that amp, which ultimately led to my selling it, were acoustic noise (JT9D), too much time to make a band change (crank, crank, crank, crank), and the silly roller inductor has a mean time to failure of about a year or so of casual operating, before the contact jumps off the track and wedges itself between turns. WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Doug Hall [SMTP:doug@nc.rr.com] > Sent: Thursday, October 18, 2001 8:04 AM > To: AMPS > Subject: RE: [AMPS] Re: 8k ultra/ "tuned input" > > > Rich wrote: > > > - Back in the days when Henry Radio did not build a 160m amplifier, a > > friend dropped by the Henry Radio booth at a ham convention. He asked a > > Henry engineer why they did not build a 3-500Z 160m amplifier. The > Henry > > engineer said that they tried it, but they discovered that 3-500Zs have > a > > cutoff frequency that's above 2MHz, so they don't work efficiently on > the > > 160m band. (sic) > > Rich, > What was the name of the engineer who made this statement? Was he actually > an engineer or just a sales guy doing booth duty? > > Doug, K4DSP > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Thu Oct 18 18:54:27 2001 From: philk5pc@tyler.net (Phil Clements) Date: Thu, 18 Oct 2001 12:54:27 -0500 Subject: [AMPS] Re: 8k ultra/ "tuned input" References: <200110181404.f9IE4lZ29345@contesting.com> Message-ID: <007b01c157fd$ef8381c0$87084c42@phil> A few words in defense of Henry is in order here.... > >-henry doesn't change the bias on cw/ssb. The bias consists of > >15-20 diodes in series in one block like a W2AW module. The > >idle current zsac goes up and down cuz of plate V difference > >between SSB V and lower cw V. Manual sez no load HV on ssb > >should be 5400V . Henry uses a 6kv plate xfmr with a choke > >input..... .9 x 6000= 5400V. They also suck a continuous > >300W of bleeder power all the time to make the tuned choke, > >look like a choke. The 3CX3000A7 runs just fine with zero bias. Henry elected to add a little bias to cut down a bit on heating of the operating area, which Texans appreciate. With a 3X3 throttled back to 3500 watts PEP, several things can be done that might not look kosher to someone designing for 6000 watts. > > If any of the 5 x 100 watt bleeders ever > >opened up, the HV would skyrocket to 8485V. And that's if you > >have the correct tap to start with. > > > // However, the filter capacitor could probably take the surge. When > the amplifier was keyed, the ZSAC acts as a bleeder current. Amen, Rich...if a bleeder failed during key-down, you still have at least an 800 watt load on the HVPS from the ZSAC from the 3X3. The filter caps are 2X-16 mfd @ 7.5 kv oils. An 8400 volt surge during bleeder failure is no big deal here. > > > The fil V should be below 7.5 V measured right at the > >socket. Life of tube is dependent on fil V. If the tube is > >lit, the clock is ticking. The tube won't last any longer cuz > >you are running it at 1500w out. If you had a 2nd amp. with > >just the tube fil lit, and no drive applied, and no HV, it > >would last just as long as your driven amp. Henry takes care of two problems in the filament circuit with one simple part. A power resistor (R617) in the primary of the filament transformer limits inrush current and allows setting of the filament voltage to the correct value for whatever line voltage that may be encountered. A filament voltmeter is included, which can be calibrated to a precision measuring source, so filament monitoring is available at the flick of a switch. > >The stock blower on the 8K ultra will not provide enough air > >for anywhere near 4kw of anode diss, more like 2500w tops. The > >stock straight up and down chimney puts quite a restriction on > >the airflow. You get what you pay for. The 8-K is rated for 3500 watts PEP MAX. No where near 4 kw dissipation...... I restate...look at the manufacturer's design targets and specs before making judgements of component selection. The cooling system is, IMO, very inovative, a la the Heath SB-220. A fiberglass cylinder is fitted from the tube anode cooler and runs up to the top cover where the hot air is exhausted through holes in the cover. Air enters from below deck through holes around the tube. There is enough air available to circulate throughout the tank circuit components before entering the anode cooler. The ambient heat build-up inside the RF deck is many degrees cooler than with conventional methods. Heat generated by the tube is segregated from the other components on the deck. > // A high-pressure blower from Kooltronics or Rotron would cure this > problem. Henry engineering is apparently clueless about manometers and > the effect of filament potential. Not in the case of the 8-K. Those wishing to exceed Henry's specs and operating instructions will need to look at Rotron et al to beef up for QRO. > > > >The henry back to back un-uns are interesting though I don't > >understand the theory behind them. They operate from 1.8-30mhz > >continuous. > > // But the SWR is somewhat less than satisfactory. The target for the 8-K was an input circuit that will guarantee <2.0-1 SWR on any frequency from 1.8-30 mhz. with a MAX drive power of only 150 watts. Also the target for feculance was >-60 db second harmonic and >-35 db IMD @ 3500 watts PEP output. By throttling the 3X3 back 2500 watts and adding a gang-tuned Pi-L tank circuit, these targets were easily met with the components Henry selected for the job. My guess is that if the intent was to produce a 6 kw amp with the same specs, you would see pi network input circuits, (it would take 18-20 of these to cover 1.8-30 mhz with no gaps) a bigger blower, and a 2.5 amp Ip meter. Also included would be a much larger price tag! Sometimes the end justifies the means. Amateurs today are not used to seeing over-engineering when they look "under the hood" of an amp. I have to admit, when Henry attempted to be competitive in the amateur market by "dumbing down" their fabulous commercial designs, some really bad mistakes were made. The 8-K is not one of these "mistakes!" (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From watson@sierracmp.com Thu Oct 18 20:52:50 2001 From: watson@sierracmp.com (George K. Watson) Date: Thu, 18 Oct 2001 13:52:50 -0600 Subject: [AMPS] Sound card two tone generation Message-ID: I seem to remember a while back some discussion of two tone generation for amplifier/transmitter testing via PC sound card. Was there any discussion of available software? I am rather keen on finishing up an amplifier I have just completed construction of and the last item left is tweaking bias. My two tone generator has converted itself into a zero tone generator and I don't have other convenient means at this point. I'll put pictures up at www.qsl.net/K0IW when I am done. Not too much to drool over though, 300W all solid state for VHF use(6m/2m). 73 all, George K. Watson K0IW -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jimr.reid@verizon.net Thu Oct 18 22:00:11 2001 From: jimr.reid@verizon.net (Jim Reid) Date: Thu, 18 Oct 2001 11:00:11 -1000 Subject: [AMPS] Re: 8k ultra/ "tuned input" References: <200110181404.f9IE4lZ29345@contesting.com> Message-ID: <001f01c15817$e4fd9280$a1040304@vz.dsl.genuity.net> Jim T. wrote, in part: > >The 8k manual also warns not to use the automatic tuner built > >into many rigs. It sez to leave the auto tuner offline, and > >just put up with any swr between xcvr and 8k ultra input. Well, not quite; here is a quote directrly from the Henry 3K/8K manual I have, Spring 1999: "Section 7: Maintenance/Troubleshooting 7.2 Input Mismatch The Ultra series of amplifiers are built with a broadband, unum type input circuit. The input SWR to the amplifier should always be better than 2:1. Experience has shown that some transceivers with automatic tuners have trouble matching this circuit. If you turn off the tuner, the transceiver should be able to drive the amplifier directly." > >The VFD wattmeter may be at fault. The henry "input" with it's > >back to back un-uns (all relay switched) may be creating some > >problems. Yes, as in that what the VFD wattmeter reads is evidently WAY too high in the power level indicated. Then Phil C. replied, in part: > You get what you pay for. The 8-K is rated for 3500 watts PEP MAX. > No where near 4 kw dissipation...... >The target for the 8-K was an input circuit that will guarantee <2.0-1 >SWR on any frequency from 1.8-30 mhz. with a MAX drive power >of only 150 watts. Well, here are the specs directly from the manual, Section 1. Henry 3K and 8K Ultra Specification: "Output Power: 3K - 1500 watts PEP or DC nominal. 8K - 5000 watts PEP or 2500 watts DC nominal Drive Power: 3K - 100 watts, 8K - up to 200 watts nominal. Duty Cycle: Continuous duty at rated output." Data supplied with my 8K, taken by Paul Johnson at Henry shows at a drive power of 200 to as high as 275 watts on both 160 and 15 meter bands, over 5000 watts of output power was measured into the big Henry dummy load. Un- loaded plate voltage was read to be 5800 at that time. Too 200 watts drive on 20 and 80 to reach such ouput power, and 230 watts drive on 40, and 250 on 10 to reach similar output powers. I have never attempted this, hi!! Don't have a dummy load to take it, and am afraid for my antenna system components! Jim T. and Rich M. both point out the need to keep the filament voltage under control: 7.5 or a bit lower, best. My mains run closer to 240 out here than 230; thus my filament voltage, as read on the Controller Unit meter is more often around 7.6. Guess I better get in there and move the transformer taps up to the 240 setting from 230, as placed by the factory, per the manual. Phil also wrote: >Henry takes care of two problems in the filament circuit with one >simple part. A power resistor (R617) in the primary of the filament >transformer limits inrush current and allows setting of the filament >voltage to the correct value for whatever line voltage that may be >encountered. A filament voltmeter is included,... Well, my 1999 manual only shows R617 in the two 3-phase PS schematics, but NOT in my single phase supply schematic; wonder why, or if the resistor is actually in the filament supply? And, R617 is not listed on the separate page which lists the power supply parts list. Anyway, very much appreciate the comments by all of you about the specs and use of this particular Henry amp. Very pleased with it, and runs just fine for me at amateur legal levels. Had it on for hours yesterday running CW practice on both 20 and 40 meters; except I just can't stand to sit and listen to 5 wpm CW, hi! Believe I am not going to be doing that speed again. Folks can get their CW up to at least 10 wpm, then I am going to offer lots of help to build skill beyond there. I am not going to worry nor bother anymore about what the actual input drive power might be; seems to be no point to it. 73, Jim KH7M -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Thu Oct 18 22:06:14 2001 From: stevek@jmr.com (Steve Katz) Date: Thu, 18 Oct 2001 14:06:14 -0700 Subject: [AMPS] Re: 8k ultra/ "tuned input" Message-ID: > Well, here are the specs directly from the manual, Section 1. > Henry 3K and 8K Ultra Specification: > > "Output Power: 3K - 1500 watts PEP or DC nominal. > 8K - 5000 watts PEP or 2500 watts DC nominal [Steve Katz] Holy cow! 1500W DC? 2500W DC? Is that, like, 2500V at 1Adc? Or 25,000V at 100 mA? Wonder how they measure it?? WB2WIK/6 > Drive Power: 3K - 100 watts, 8K - up to 200 watts nominal. > > Duty Cycle: Continuous duty at rated output." > > Data supplied with my 8K, taken by Paul Johnson at Henry > shows at a drive power of 200 to as high as 275 watts on > both 160 and 15 meter bands, over 5000 watts of output > power was measured into the big Henry dummy load. Un- > loaded plate voltage was read to be 5800 at that time. > Too 200 watts drive on 20 and 80 to reach such ouput > power, and 230 watts drive on 40, and 250 on 10 to > reach similar output powers. I have never attempted this, hi!! > Don't have a dummy load to take it, and am afraid for my > antenna system components! > > Jim T. and Rich M. both point out the need to keep the > filament voltage under control: 7.5 or a bit lower, best. > My mains run closer to 240 out here than 230; thus > my filament voltage, as read on the Controller Unit > meter is more often around 7.6. Guess I better get in there > and move the transformer taps up to the 240 setting from > 230, as placed by the factory, per the manual. > > Phil also wrote: > > >Henry takes care of two problems in the filament circuit with one > >simple part. A power resistor (R617) in the primary of the filament > >transformer limits inrush current and allows setting of the filament > >voltage to the correct value for whatever line voltage that may be > >encountered. A filament voltmeter is included,... > > Well, my 1999 manual only shows R617 in the two 3-phase > PS schematics, but NOT in my single phase supply schematic; > wonder why, or if the resistor is actually in the filament supply? > And, R617 is not listed on the separate page which lists the > power supply parts list. > > Anyway, very much appreciate the comments by all of you > about the specs and use of this particular Henry amp. Very > pleased with it, and runs just fine for me at amateur legal > levels. Had it on for hours yesterday running CW practice > on both 20 and 40 meters; except I just can't stand to sit > and listen to 5 wpm CW, hi! Believe I am not going to be > doing that speed again. Folks can get their CW up to > at least 10 wpm, then I am going to offer lots of help to > build skill beyond there. > > I am not going to worry nor bother anymore about what > the actual input drive power might be; seems to be no > point to it. > > 73, Jim KH7M > > > > > > > > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Thu Oct 18 22:49:12 2001 From: 2@vc.net (2) Date: Thu, 18 Oct 2001 14:49:12 -0700 Subject: [AMPS] Re: 8k ultra/ "tuned input" Message-ID: <200110182148.f9ILmaZ04219@contesting.com> > >Rich wrote: > >> - Back in the days when Henry Radio did not build a 160m amplifier, a >> friend dropped by the Henry Radio booth at a ham convention. He asked a >> Henry engineer why they did not build a 3-500Z 160m amplifier. The Henry >> engineer said that they tried it, but they discovered that 3-500Zs have a >> cutoff frequency that's above 2MHz, so they don't work efficiently on the >> 160m band. (sic) > >Rich, >What was the name of the engineer who made this statement? Was he actually >an engineer or just a sales guy doing booth duty? > // The friend said the "engineer" looked to be Asian, but I do not remember the name. Sorry. - Other interesting Henry Radio achievements: 1. Four models of 3-500Z amplifiers that applied from 5.8 to 6.0 volts to the filament. 2. A 5CX1500A amplifier that had 280Arms of filament inrush current. 3. One of the highest VHF-Rp suppressor designs in ham amplifiers. 4. No stepstart in the 2k-3, 2k-4, et cetera. 5. Glitch resistor in the HV negative circuitry. cheers, Doug - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jimr.reid@verizon.net Thu Oct 18 23:21:21 2001 From: jimr.reid@verizon.net (Jim Reid) Date: Thu, 18 Oct 2001 12:21:21 -1000 Subject: [AMPS] Re: 8k ultra/ "tuned input" References: Message-ID: <000d01c15823$3d9d4060$a1040304@vz.dsl.genuity.net> > > 8K - 5000 watts PEP or 2500 watts DC nominal > [Steve Katz] Holy cow! 1500W DC? 2500W DC? Is that, like, 2500V > at 1Adc? Or 25,000V at 100 mA? Wonder how they measure it?? I believe what they are spec'ing with the "2500 watts DC" is continuous duty cycle, or constant CW key down power out, all day. Not the same as CCS, which means Continuous Commercial Service. I believe that at some overseas SW broadcast stations which use this amp, they are running CCS at 4 to 5 kW out all day on either SSB or AM, but not positive. 73, Jim KH7M -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From KevNathan@DSB.WA.GOV Thu Oct 18 23:22:53 2001 From: KevNathan@DSB.WA.GOV (Nathan, Kevin) Date: Thu, 18 Oct 2001 15:22:53 -0700 Subject: [AMPS] Ameritron ALS-600 Message-ID: <599508F047222543998E761F0496C1CE07037A@dsb1mloly1.dsb1.wa.gov> Hi All, I am new to the reflector although I was here a few years back. I have an Ameritron ALS-600 solid state amp which I like very much. The transceiver I use with it is the Icom IC-746. I am totally blind and it is very easy for me to use this amp. There is just one small problem I hope someone on this list may have experienced and for which I hope there is an easy cure. When I key the amp on CW, it does not reach full power instantaneously. Therefore, the dits of a code character, particularly if they are the lead item sent, aren't always sent at full power. I have an audio device that indicates actual RF, not meter readings, and this device takes a perceivable fraction of a second to reach its highest pitch which indicates maximum RF through it. Does anyone on the list have any idea as to what may cause this and what the fix might be? I am subscribed to this list at my work address so please also address any feedback you have for me to my home email which is k7rx@earthlink.net. Thanks much and 73. Kevin, K7RX Kevin Nathan, Independent Living Coordinator Dept. of Services for the Blind 3411 S. Alaska Seattle, Wa 98118 Voice: (206) 721-6450 Toll Free: (800) 552-7103 Fax: (206) 721-6403 Email: kevnathan@dsb.wa.gov -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Thu Oct 18 23:18:21 2001 From: stevek@jmr.com (Steve Katz) Date: Thu, 18 Oct 2001 15:18:21 -0700 Subject: [AMPS] Re: 8k ultra/ "tuned input" Message-ID: I understand the misnomer, Jim. I see it used all the time, but I cringe when I think my amplifier might be putting out DC. The RF hazards to the neighborhood are bad enough, but if I add a few kilovolts DC to the antennas, somebody might really get hurt... WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Jim Reid [SMTP:jimr.reid@verizon.net] > Sent: Thursday, October 18, 2001 3:21 PM > To: Steve Katz; 2; Jim Thomson; w8ji@akorn.net; AMPS; Phil Clements > Subject: Re: [AMPS] Re: 8k ultra/ "tuned input" > > > > > 8K - 5000 watts PEP or 2500 watts DC nominal > > [Steve Katz] Holy cow! 1500W DC? 2500W DC? Is that, like, 2500V > > at 1Adc? Or 25,000V at 100 mA? Wonder how they measure it?? > > I believe what they are spec'ing with the "2500 watts DC" is > continuous duty cycle, or constant CW key down power > out, all day. Not the same as CCS, which > means Continuous Commercial Service. I believe that > at some overseas SW broadcast stations which use this amp, > they are running CCS at 4 to 5 kW out all day on > either SSB or AM, but not positive. > > 73, Jim KH7M -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Thu Oct 18 23:34:16 2001 From: stevek@jmr.com (Steve Katz) Date: Thu, 18 Oct 2001 15:34:16 -0700 Subject: [AMPS] Ameritron ALS-600 Message-ID: When using break-in, where your exciter keys the amplifier an instant after you close your CW key, this is a very normal "problem." It can be solved a variety of ways. One way that comes to mind and is probably the most effective is to let your keyer key the amp, and have the amp key your IC-746. No joke. This is actually a whole lot smarter, because it will assure the T/R relay in the amplifier is closed prior to applying excitation (drive) to the amplifier. When you key the IC-746, and use it to key the amplifier, you are "hot keying" your amplifier, e.g., RF output is reaching your amplifier at the same time as it's receiving the signal to switch its internal T/R relay. What I proposed involves additional, after-market circuitry. Ameritron's QSK switch does exactly this, and is available as a rather expensive accessory. When you use their QSK switch, your keyer plugs into the switch, and the switch activates the exciter and the amplifier, and there is no "slow start-up" when the first dit is sent. A less expensive route is to simply manually key your amplifier before you start to send. This is obviously not QSK, and takes a tiny extra effort, but I've used a foot switch for such applications many times, and once you're used to it, it becomes so natural it's almost like QSK -- except without the "slow start-up" that you've noted. That's eliminated, because your amp is keyed first, then the exciter. 73 de Steve WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Nathan, Kevin [SMTP:KevNathan@DSB.WA.GOV] > Sent: Thursday, October 18, 2001 3:23 PM > To: 'amps@contesting.com' > Subject: [AMPS] Ameritron ALS-600 > > > Hi All, > > I am new to the reflector although I was here a few years back. I have an > Ameritron ALS-600 solid state amp which I like very much. The transceiver > I > use with it is the Icom IC-746. I am totally blind and it is very easy > for > me to use this amp. > > There is just one small problem I hope someone on this list may have > experienced and for which I hope there is an easy cure. When I key the > amp > on CW, it does not reach full power instantaneously. Therefore, the dits > of > a code character, particularly if they are the lead item sent, aren't > always > sent at full power. I have an audio device that indicates actual RF, not > meter readings, and this device takes a perceivable fraction of a second > to > reach its highest pitch which indicates maximum RF through it. Does > anyone > on the list have any idea as to what may cause this and what the fix might > be? > > I am subscribed to this list at my work address so please also address any > feedback you have for me to my home email which is k7rx@earthlink.net. > > Thanks much and 73. > Kevin, K7RX > > Kevin Nathan, Independent Living Coordinator > Dept. of Services for the Blind > 3411 S. Alaska > Seattle, Wa 98118 > Voice: (206) 721-6450 > Toll Free: (800) 552-7103 > Fax: (206) 721-6403 > Email: kevnathan@dsb.wa.gov > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Fri Oct 19 00:07:39 2001 From: philk5pc@tyler.net (Phil Clements) Date: Thu, 18 Oct 2001 18:07:39 -0500 Subject: [AMPS] Ameritron ALS-600 References: <599508F047222543998E761F0496C1CE07037A@dsb1mloly1.dsb1.wa.gov> Message-ID: <011501c15829$b072c6e0$87084c42@phil> Hi Kevin, and welcome to the amps reflector! I have a similar set-up here. It is an Icom 706 Mark II and a Henry SS-750 amp. It is my mobile rig for long trips, but 99% of the time it is right here on my desk. I call it my "spot and pounce" station. When a needed country is spotted on the DX cluster, an alarm goes off, and the 706 is automatically tuned to the frequency(s) and mode All I have to do is throw the proper band switch on the Henry and I usually have the 'new one" in the log. One click on the computer keyboard, and its logged. I still have my eyesight, but it is going down hill fairly fast. This is an ideal set-up for this. I also chose the Ameritron QSK-5 to handle the QSK chores for me. It not only works mobile and fixed, but it also switches several other amps at my station. It is a "stand alone" unit; self- powered. It switches several times faster than the fastest vacuum relay. Tales of lightning susceptibility are highly exaggerated. I try not to operate QSK during thunderstorms, and I disconnect my antennas. This procedure has been successful for 5+ years here in tornado alley. (not so for several antennas and one tower!) The QSK-5, IMO, is a good investment, and will work with any equipment you my acquire in the future. GL! (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 19 00:19:19 2001 From: 2@vc.net (2) Date: Thu, 18 Oct 2001 16:19:19 -0700 Subject: [AMPS] Ameritron ALS-600 Message-ID: <200110182318.f9INIhZ06293@contesting.com> > >... ... ... >I also chose the Ameritron QSK-5 to handle the QSK chores >for me. It not only works mobile and fixed, but it also switches >several other amps at my station. It is a "stand alone" unit; self- >powered. It switches several times faster than the fastest vacuum >relay. Tales of lightning susceptibility are highly exaggerated. I try >not to operate QSK during thunderstorms, and I disconnect my >antennas. // A wise decision. A friend who lives in the lightning belt told me he saw evidence of a several foot arc in a ham shack when lightning struck the antenna and followed the feedline. - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Fri Oct 19 01:07:07 2001 From: W8JI@contesting.com (Tom Rauch) Date: Thu, 18 Oct 2001 20:07:07 -0400 Subject: [AMPS] Re: 8k ultra/ "tuned input" In-Reply-To: <001f01c15817$e4fd9280$a1040304@vz.dsl.genuity.net> Message-ID: <3BCF366B.10008.153894A3@localhost> > Well, here are the specs directly from the manual, Section 1. > Henry 3K and 8K Ultra Specification: > > "Output Power: 3K - 1500 watts PEP or DC nominal. > 8K - 5000 watts PEP or 2500 watts DC nominal How do you get DC out of an RF amplifier? 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jimr.reid@verizon.net Fri Oct 19 02:34:07 2001 From: jimr.reid@verizon.net (Jim Reid) Date: Thu, 18 Oct 2001 15:34:07 -1000 Subject: [AMPS] Re: 8k ultra/ "tuned input" References: <3BCF366B.10008.153894A3@localhost> Message-ID: <001a01c1583e$27754ce0$a1040304@vz.dsl.genuity.net> > > "Output Power: 3K - 1500 watts PEP or DC nominal. > > 8K - 5000 watts PEP or 2500 watts DC nominal > > How do you get DC out of an RF amplifier? I believe what they are spec'ing with the "2500 watts DC" is continuous duty cycle, or constant CW key down power out, all day. Not the same as CCS, which means Continuous Commercial Service. I believe that at some overseas SW broadcast stations which use this amp, they are running CCS at 4+kW out all day on either SSB or AM, but not positive. 73, Jim KH7M -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 19 03:08:28 2001 From: 2@vc.net (2) Date: Thu, 18 Oct 2001 19:08:28 -0700 Subject: [AMPS] Re: 8k ultra/ "tuned input" Message-ID: <200110190207.f9J27pZ11968@contesting.com> > >> Well, here are the specs directly from the manual, Section 1. >> Henry 3K and 8K Ultra Specification: >> >> "Output Power: 3K - 1500 watts PEP or DC nominal. >> 8K - 5000 watts PEP or 2500 watts DC nominal > >How do you get DC out of an RF amplifier? // Piece o' cake: Jumper across the DC blocking capacitor and remove the RFC across the loading capacitor. - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Fri Oct 19 07:34:52 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Fri, 19 Oct 2001 07:34:52 +0100 Subject: [AMPS] Re: 8k ultra/ "tuned input" Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A9C5@excalibur.swindon.msl.mitel.com> Tom says: >How do you get DC out of an RF amplifier? Rectify the output? remove the plate blocking cap and fit a short circuit? let the marketing department loose? 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Fri Oct 19 07:43:43 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Fri, 19 Oct 2001 07:43:43 +0100 Subject: [AMPS] Re: 8k ultra/ "tuned input" Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A9C6@excalibur.swindon.msl.mitel.com> Rich said: >" but they discovered that 3-500Zs have a cutoff frequency that's above 2MHz" I expect Rich, that you managed a wry smile on hearing that! Maybe it's because the large electrode spacing is such that at low frequencies, the electrons haven't reached the plate before the grid phase changes, and they get lost. Or maybe accelerated so much that they heat the plate up instead of providing RF out? Phineas T. had it about right............... 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From AC5YV@hot.rr.com Fri Oct 19 12:10:47 2001 From: AC5YV@hot.rr.com (Richard) Date: Fri, 19 Oct 2001 06:10:47 -0500 Subject: [AMPS] Eimac Mechanical Sample Message-ID: <01f501c1588e$b4680200$c86aa218@hot.rr.com> This is a multi-part message in MIME format. ------=_NextPart_000_01F2_01C15864.CB57FE40 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable All, need some help. I have a floor mount Harris amp, huge device but = it has served me well. It uses a 4cx1500 of which I have several. My = question is I have two 4cx1500A's that are brand new and marked = "Mechanical Sample" in the same "Red" screen as the words "Eimac = 4CX1500A". =20 Has anyone any knowledge of what these are? I am not going to put them = in the amp as I suspect they are dummy "Fitting type" tubes produced for = some reason. Any help would be appreciated, am I right about the dummy load, or since = they came from the Harris Factory are they good tubes? Thanks Richard AC5YV ------=_NextPart_000_01F2_01C15864.CB57FE40 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
All, need some help. I have a = floor mount=20 Harris amp, huge device but it has served me well. It uses a = 4cx1500 of=20 which I have several. My question is I have two 4cx1500A's that = are brand=20 new and marked "Mechanical Sample" in the same "Red" screen as the = words=20 "Eimac 4CX1500A".

Has anyone any knowledge of what these = are? I=20 am not going to put them in the amp as I suspect they are dummy "Fitting = type"=20 tubes produced for some reason.

Any help would be appreciated, am I = right about the=20 dummy load, or since they came from the Harris Factory are they good=20 tubes?

Thanks

Richard

AC5YV
------=_NextPart_000_01F2_01C15864.CB57FE40-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 19 14:26:51 2001 From: 2@vc.net (2) Date: Fri, 19 Oct 2001 06:26:51 -0700 Subject: [AMPS] Re: 8k ultra/ "tuned input" Message-ID: <200110191326.f9JDQEZ19751@contesting.com> > >Rich said: > >>" but they discovered that 3-500Zs have a cutoff frequency that's above 2MHz" > >I expect Rich, that you managed a wry smile on hearing that! > // I chortled. >Maybe it's because the large electrode spacing is such that at low frequencies, >the electrons haven't reached the plate before the grid phase changes, and they >get lost. Or maybe accelerated so much that they heat the plate up instead of >providing RF out? > // The latter sounds a tad more incredible. "I can believe anything, provided it is incredible." - Oscar Wilde On the other hand, if the plate/anode contains any Ni and Cr, perhaps the Rauchian phenomenon of increasing RF R with decreasing frequency is a factor below 3MHz? >Phineas T. had it about right............... > // Phineas Taylor Barnum ( 1810-1891), the Great American Master of sucker fleecing. > cheers, Peter - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Wlfuqu00@uky.edu Fri Oct 19 14:12:50 2001 From: Wlfuqu00@uky.edu (wlfuqu00@uky.edu) Date: Fri, 19 Oct 2001 09:12:50 -0400 Subject: Fwd: [AMPS] Need 1500T to compete collection Message-ID: <5.0.0.25.2.20011019091219.03e0c650@mail.uky.edu> I am in need of a EIMAC 1500T to complete my EIMAC Glass Triode Tube Collection. Please contact me if you have or know of one for sale or trade. 73 Bill wa4lav -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From kd5izi_tech@yahoo.com Fri Oct 19 14:55:14 2001 From: kd5izi_tech@yahoo.com (Randall DuCharme) Date: Fri, 19 Oct 2001 06:55:14 -0700 (PDT) Subject: [AMPS] Calculating input impedance and drive requirements? Message-ID: <20011019135514.33779.qmail@web20005.mail.yahoo.com> Greetings gurus, I'm a little bit lost.... I'm unsure as to the correct mathematics and methods to calculate the input impedance and drive requirements of an amplifier stage. Seems that I need this info in order to design the inputs. The project at hand is a 4x813 HF amp, cathode-driven, with bypassed screen and bias supplies. Hoping this isn't a ridiculously stupid question :-) Many thanks in advance for any assistance! Kind Regards (KD5IZI/AE) __________________________________________________ Do You Yahoo!? Make a great connection at Yahoo! Personals. http://personals.yahoo.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ve3tu@rac.ca Fri Oct 19 14:11:31 2001 From: ve3tu@rac.ca (Steve) Date: Fri, 19 Oct 2001 14:11:31 +0100 Subject: [AMPS] Ameritron ALS-600 References: <599508F047222543998E761F0496C1CE07037A@dsb1mloly1.dsb1.wa.gov> Message-ID: <3BD02683.56154238@rac.ca> Hi Kevin, I have noticed the same operation on other rigs. If your rig has an internal tuner try it with the tuner on. I have noticed that the slow ramp up of the output is gone with the tuner on. If the condition is caused by the amp I cannot help since I have no experience with that model. gl es 73 Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From dhearn@ix.netcom.com Fri Oct 19 15:54:00 2001 From: dhearn@ix.netcom.com (dan hearn) Date: Fri, 19 Oct 2001 07:54:00 -0700 Subject: [AMPS] Eimac Mechanical Sample References: <01f501c1588e$b4680200$c86aa218@hot.rr.com> Message-ID: <3BD03E88.8A1F58E7@ix.netcom.com> Hi Richard: I lived in Dallas until 3 years ago. A number of years back there was a guy there who built and sold a number of linears using 8877 tubes, All of the tubes were marked Mechanical Sample. He told me that he was trading TI calculators to someone at Eimac for the tubes. He worked at TI. My next door neighbor in Fairview was and I believe still is a sales engineer for Varian. When the sales office in Keystone Park, near TI closed, he worked out of his home. One day he asked me if I was interested in some tubes which went to him when the office closed. He gave me a new 8877 with chimney and socket, and a 3-500z which was stamped mechanical sample. Inside the box was a set of test data and a note saying the tube was OK. I believe many tubes are in existence marked mechanical sample which are good tubes. I have not used the 3-500 but am pretty sure it is a new, first class tube. 73, Dan, N5AR > Richard wrote: > > All, need some help. I have a floor mount Harris amp, huge device but > it has served me well. It uses a 4cx1500 of which I have several. My > question is I have two 4cx1500A's that are brand new and marked > "Mechanical Sample" in the same "Red" screen as the words "Eimac > 4CX1500A". > Has anyone any knowledge of what these are? I am not going to put > them in the amp as I suspect they are dummy "Fitting type" tubes > produced for some reason. > > Any help would be appreciated, am I right about the dummy load, or > since they came from the Harris Factory are they good tubes? > > Thanks > > Richard > AC5YV -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 19 16:17:19 2001 From: 2@vc.net (2) Date: Fri, 19 Oct 2001 08:17:19 -0700 Subject: [AMPS] Eimac Mechanical Sample Message-ID: <200110191516.f9JFGkZ21661@contesting.com> > >Hi Richard: I lived in Dallas until 3 years ago. A number of years back >there was a guy there who built and sold a number of linears using 8877 >tubes, All of the tubes were marked Mechanical Sample. He told me that >he was trading TI calculators to someone at Eimac for the tubes. He >worked at TI. > My next door neighbor in Fairview was and I believe still is a sales >engineer for Varian. When the sales office in Keystone Park, near TI >closed, he worked out of his home. One day he asked me if I was >interested in some tubes which went to him when the office closed. He >gave me a new 8877 with chimney and socket, and a 3-500z which was >stamped mechanical sample. Inside the box was a set of test data and a >note saying the tube was OK. I believe many tubes are in existence >marked mechanical sample which are good tubes. I have not used the 3-500 >but am pretty sure it is a new, first class tube. // The Mechanical Sanples may have been tubes that were slightly out of spec. but still worked well enough. cheers, Dan > >> Richard wrote: >> >> All, need some help. I have a floor mount Harris amp, huge device but >> it has served me well. It uses a 4cx1500 of which I have several. My >> question is I have two 4cx1500A's that are brand new and marked >> "Mechanical Sample" in the same "Red" screen as the words "Eimac >> 4CX1500A". >> Has anyone any knowledge of what these are? I am not going to put >> them in the amp as I suspect they are dummy "Fitting type" tubes >> produced for some reason. >> >> Any help would be appreciated, am I right about the dummy load, or >> since they came from the Harris Factory are they good tubes? >> >> Thanks >> >> Richard >> AC5YV > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Fri Oct 19 16:18:28 2001 From: stevek@jmr.com (Steve Katz) Date: Fri, 19 Oct 2001 08:18:28 -0700 Subject: [AMPS] Eimac Mechanical Sample Message-ID: Could be anything, but in the semiconductor industry, of which I was a part for about 20 years, it was very common to permanently mark anything of considerable value which was being carried around by salesmen as "Mechanical Sample. Not for Sale" or something similar, so we could travel back and forth across international borders (even between the U.S. and Canada) and make it through customs without having to declare these items and fill out a lot of forms. The products were new, right off the production line, and as good as anything else. We were just short-cutting the customs agents. WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: 2 [SMTP:2@vc.net] > Sent: Friday, October 19, 2001 8:17 AM > To: dhearn@ix.netcom.com; Richard; AMPS > Subject: Re: [AMPS] Eimac Mechanical Sample > > > > > >Hi Richard: I lived in Dallas until 3 years ago. A number of years back > >there was a guy there who built and sold a number of linears using 8877 > >tubes, All of the tubes were marked Mechanical Sample. He told me that > >he was trading TI calculators to someone at Eimac for the tubes. He > >worked at TI. > > My next door neighbor in Fairview was and I believe still is a sales > >engineer for Varian. When the sales office in Keystone Park, near TI > >closed, he worked out of his home. One day he asked me if I was > >interested in some tubes which went to him when the office closed. He > >gave me a new 8877 with chimney and socket, and a 3-500z which was > >stamped mechanical sample. Inside the box was a set of test data and a > >note saying the tube was OK. I believe many tubes are in existence > >marked mechanical sample which are good tubes. I have not used the 3-500 > >but am pretty sure it is a new, first class tube. > > // The Mechanical Sanples may have been tubes that were slightly out of > spec. but still worked well enough. > > cheers, Dan > > > >> Richard wrote: > >> > >> All, need some help. I have a floor mount Harris amp, huge device but > >> it has served me well. It uses a 4cx1500 of which I have several. My > >> question is I have two 4cx1500A's that are brand new and marked > >> "Mechanical Sample" in the same "Red" screen as the words "Eimac > >> 4CX1500A". > >> Has anyone any knowledge of what these are? I am not going to put > >> them in the amp as I suspect they are dummy "Fitting type" tubes > >> produced for some reason. > >> > >> Any help would be appreciated, am I right about the dummy load, or > >> since they came from the Harris Factory are they good tubes? > >> > >> Thanks > >> > >> Richard > >> AC5YV > > > >-- > >FAQ on WWW: http://www.contesting.com/FAQ/amps > >Submissions: amps@contesting.com > >Administrative requests: amps-REQUEST@contesting.com > >Problems: owner-amps@contesting.com > > > > > > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. > end > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Jim" Message-ID: <001001c158ba$80537900$897a9e40@jims> I have a 3-500Z tube at home that is labeled "Electrical Sample". 73 Jim W7RY ----- Original Message ----- From: "Steve Katz" To: "'2'" <2@vc.net>; ; "Richard" ; "AMPS" Sent: Friday, October 19, 2001 8:18 AM Subject: RE: [AMPS] Eimac Mechanical Sample > > Could be anything, but in the semiconductor industry, of which I was a part > for about 20 years, it was very common to permanently mark anything of > considerable value which was being carried around by salesmen as "Mechanical > Sample. Not for Sale" or something similar, so we could travel back and > forth across international borders (even between the U.S. and Canada) and > make it through customs without having to declare these items and fill out a > lot of forms. The products were new, right off the production line, and as > good as anything else. We were just short-cutting the customs agents. > > WB2WIK/6 > > "Each success only buys an admission ticket to a more difficult problem." -- > Henry Kissinger > > > -----Original Message----- > > From: 2 [SMTP:2@vc.net] > > Sent: Friday, October 19, 2001 8:17 AM > > To: dhearn@ix.netcom.com; Richard; AMPS > > Subject: Re: [AMPS] Eimac Mechanical Sample > > > > > > > > > >Hi Richard: I lived in Dallas until 3 years ago. A number of years back > > >there was a guy there who built and sold a number of linears using 8877 > > >tubes, All of the tubes were marked Mechanical Sample. He told me that > > >he was trading TI calculators to someone at Eimac for the tubes. He > > >worked at TI. > > > My next door neighbor in Fairview was and I believe still is a sales > > >engineer for Varian. When the sales office in Keystone Park, near TI > > >closed, he worked out of his home. One day he asked me if I was > > >interested in some tubes which went to him when the office closed. He > > >gave me a new 8877 with chimney and socket, and a 3-500z which was > > >stamped mechanical sample. Inside the box was a set of test data and a > > >note saying the tube was OK. I believe many tubes are in existence > > >marked mechanical sample which are good tubes. I have not used the 3-500 > > >but am pretty sure it is a new, first class tube. > > > > // The Mechanical Sanples may have been tubes that were slightly out of > > spec. but still worked well enough. > > > > cheers, Dan > > > > > >> Richard wrote: > > >> > > >> All, need some help. I have a floor mount Harris amp, huge device but > > >> it has served me well. It uses a 4cx1500 of which I have several. My > > >> question is I have two 4cx1500A's that are brand new and marked > > >> "Mechanical Sample" in the same "Red" screen as the words "Eimac > > >> 4CX1500A". > > >> Has anyone any knowledge of what these are? I am not going to put > > >> them in the amp as I suspect they are dummy "Fitting type" tubes > > >> produced for some reason. > > >> > > >> Any help would be appreciated, am I right about the dummy load, or > > >> since they came from the Harris Factory are they good tubes? > > >> > > >> Thanks > > >> > > >> Richard > > >> AC5YV > > > > > >-- > > >FAQ on WWW: http://www.contesting.com/FAQ/amps > > >Submissions: amps@contesting.com > > >Administrative requests: amps-REQUEST@contesting.com > > >Problems: owner-amps@contesting.com > > > > > > > > > > > > - R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures. > > end > > > > > > -- > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > Submissions: amps@contesting.com > > Administrative requests: amps-REQUEST@contesting.com > > Problems: owner-amps@contesting.com > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jtml@lanl.gov Fri Oct 19 19:30:40 2001 From: jtml@lanl.gov (John Lyles) Date: Fri, 19 Oct 2001 12:30:40 -0600 Subject: [AMPS] propagation Message-ID: The medium can't get much wierder than this.... check it out: > >>Space Weather News for October 19, 2001 >>http://www.spaceweather.com >> >>Twisted magnetic fields above sunspot 9661 erupted this morning, >>unleashing an X-class solar flare and hurling a coronal mass ejection >>toward Earth. The expanding cloud will likely strike our planet's >>magnetosphere on October 21st during the peak of the Orionid meteor >>shower. Sky watchers, especially those living at higher latitudes, could >>spot both meteors and auroras this weekend. Stay tuned to >>SpaceWeather.com for details and updates. -- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Fri Oct 19 20:11:01 2001 From: W8JI@contesting.com (Tom Rauch) Date: Fri, 19 Oct 2001 15:11:01 -0400 Subject: [AMPS] Calculating input impedance and drive requirements? In-Reply-To: <20011019135514.33779.qmail@web20005.mail.yahoo.com> Message-ID: <3BD04285.737.19500318@localhost> > I'm unsure as to the correct mathematics and methods > to calculate the input impedance and drive > requirements of an amplifier stage. Seems that I need > this info in order to design the inputs. > > The project at hand is a 4x813 HF amp, cathode-driven, > with bypassed screen and bias supplies. Actually that question is too complex, because characteristic curves for GG 813's is almost certainly not available. The fastest and best (and probably only) thing is to measure the driving impedance in your actual circuit, or maybe find someone who already has measured it. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jimr.reid@verizon.net Sat Oct 20 00:19:58 2001 From: jimr.reid@verizon.net (Jim Reid) Date: Fri, 19 Oct 2001 13:19:58 -1000 Subject: [AMPS] 8k ultra Fil V. References: <200110181404.f9IE4lZ29345@contesting.com> Message-ID: <000f01c158f4$9e46f740$a1040304@vz.dsl.genuity.net> Couple days ago, it was written about the 3CX3000A7: > > The fil V should be below 7.5 V measured right at the > >socket. Life of tube is dependent on fil V. > > // Excellent points, Jim. Few designers seem to realize that the > emissive life of a thoriated-tungsten cathode/filament is cut in Half for > each 3% increase in filament voltage above what is needed to achieve full > PEP. Thus, the formula for emissive life vs fil. volts = (e1/e2)^23.4. Per Henry, the Controller Unit filament voltage meter selection is "calibrated" to actually "read" the voltage at the tube filament pins. My filament has been at about 7.6 v, above the mid-point of 7.5 +/- 5%, or 7.12 to 7.87 volts. This morning I operated, (actually as a bit of a contortionist). Henry placed the filament transformer quite buried within the PS assembly. However, removing a side panel, laying on the floor with a flash light and hot soldering iron at the tip of my nose, I was able to move the primary tap to the end #6 tap. Result: filament voltage is now 7.3 volts. So the emissive life, per the formula ought to be a bunch longer! This action has lowered the filament voltage 3.9% below the original 7.6v. I presume that even 7.12v would be enough to reach full PEP, per the above. Left the HV tap where it was, so when the SSB PS setting is selected, the key-up plate voltage reads 5800v, and just under 4400v when lowering the voltage by the CW relay selected HV xfmr secondary tap. Thanks for alerting me to this tube life prolonging act. 73, Jim KH7M -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Sat Oct 20 00:21:07 2001 From: stevek@jmr.com (Steve Katz) Date: Fri, 19 Oct 2001 16:21:07 -0700 Subject: [AMPS] 8k ultra Fil V. Message-ID: The 3CX3000A7 has a thoriated tungsten filament? "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Jim Reid [SMTP:jimr.reid@verizon.net] > Sent: Friday, October 19, 2001 4:20 PM > To: 2; Jim Thomson; w8ji@akorn.net; AMPS; Chuck Counselman > Subject: [AMPS] 8k ultra Fil V. > > > > Couple days ago, it was written about the 3CX3000A7: > > > > The fil V should be below 7.5 V measured right at the > > >socket. Life of tube is dependent on fil V. > > > > // Excellent points, Jim. Few designers seem to realize that the > > emissive life of a thoriated-tungsten cathode/filament is cut in Half > for > > each 3% increase in filament voltage above what is needed to achieve > full > > PEP. Thus, the formula for emissive life vs fil. volts = (e1/e2)^23.4. > > Per Henry, the Controller Unit filament voltage meter selection is > "calibrated" to actually "read" the voltage at the tube filament > pins. > > My filament has been at about 7.6 v, above the mid-point of > 7.5 +/- 5%, or 7.12 to 7.87 volts. This morning I operated, > (actually as a bit of a contortionist). Henry placed the filament > transformer quite buried within the PS assembly. However, > removing a side panel, laying on the floor with a flash light > and hot soldering iron at the tip of my nose, I was able to > move the primary tap to the end #6 tap. Result: filament > voltage is now 7.3 volts. So the emissive life, per the formula > ought to be a bunch longer! This action has lowered the filament > voltage 3.9% below the original 7.6v. I presume that even 7.12v > would be enough to reach full PEP, per the above. > > Left the HV tap where it was, so when the SSB PS setting is > selected, the key-up plate voltage reads 5800v, and just under > 4400v when lowering the voltage by the CW relay selected HV > xfmr secondary tap. > > Thanks for alerting me to this tube life prolonging act. > > 73, Jim KH7M > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jimr.reid@verizon.net Sat Oct 20 00:32:22 2001 From: jimr.reid@verizon.net (Jim Reid) Date: Fri, 19 Oct 2001 13:32:22 -1000 Subject: [AMPS] 8k ultra Fil V. References: Message-ID: <000501c158f6$56043540$a1040304@vz.dsl.genuity.net> > The 3CX3000A7 has a thoriated tungsten filament? >From an Eimac reference sheet: "Filament/Cathode......Thoriated Tungsten Voltage.....7.5 Volts Current.... 51.5 Amps" See: http://www.eimac.com/catalog/17235.htm 73, Jim KH7M -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From KevNathan@DSB.WA.GOV Sat Oct 20 00:36:05 2001 From: KevNathan@DSB.WA.GOV (Nathan, Kevin) Date: Fri, 19 Oct 2001 16:36:05 -0700 Subject: [AMPS] ALS-600 Message-ID: <599508F047222543998E761F0496C1CE07039A@dsb1mloly1.dsb1.wa.gov> Thanks to those who responded with ideas for me to try. I will do some experimentation to see if I can solve the problem. I appreciate your input. I am going to drop off the list now to minimize email here at work. Again, thanks and 73 Kevin, K7RX Kevin Nathan, Independent Living Coordinator Dept. of Services for the Blind 3411 S. Alaska Seattle, Wa 98118 Voice: (206) 721-6450 Toll Free: (800) 552-7103 Fax: (206) 721-6403 Email: kevnathan@dsb.wa.gov -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Sat Oct 20 03:04:37 2001 From: philk5pc@tyler.net (Phil Clements) Date: Fri, 19 Oct 2001 21:04:37 -0500 Subject: [AMPS] 8k ultra Fil V. References: Message-ID: <000901c1590b$94bfe1c0$f1084c42@phil> > The 3CX3000A7 has a thoriated tungsten filament? Yes; 7.5 volts @ 51.5 amps...no warm-up required. (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From JimMoci@aol.com Sat Oct 20 18:17:59 2001 From: JimMoci@aol.com (JimMoci@aol.com) Date: Sat, 20 Oct 2001 13:17:59 EDT Subject: [AMPS] Use of Svetlana. 4CX800 in amp Message-ID: --part1_c9.17426526.29030bc7_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Has anyone used the Svetlana 4CX800 in grounded grid (on HF) by tying the screen and control grid together? Is it ok to do with this tube? There is and inexpensive and plentiful source for these tubes on E-pay and I am giving some thought to buying a few of these tubes. Thanks, Jim --part1_c9.17426526.29030bc7_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit Has anyone used the Svetlana 4CX800 in grounded grid (on HF) by tying the screen and control grid together? Is it ok to do with this tube? There is and inexpensive and plentiful source for these tubes on E-pay and I am giving some thought to buying a few of these tubes.
Thanks,
Jim --part1_c9.17426526.29030bc7_boundary-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sat Oct 20 19:12:13 2001 From: 2@vc.net (2) Date: Sat, 20 Oct 2001 11:12:13 -0700 Subject: [AMPS] Use of Svetlana. 4CX800 in amp Message-ID: <200110201811.f9KIBZZ15135@contesting.com> >Has anyone used the Svetlana 4CX800 in grounded grid (on HF) by tying the >screen and control grid together? Is it ok to do with this tube? There is >and >inexpensive and plentiful source for these tubes on E-pay and I am giving >some thought to buying a few of these tubes. >Thanks, >Jim > The 4cx800 is a Class AB1 tetrode that has a 2w max diss, grid. The grid normal runs 0w diss. In grounded-grid, there is substantial grid current. Typical g-g service tubes have c. 20w grids. - Running AB1 is easier than building a g-g tuned input circuit for each band that is going to be affected by the length of coax to, and the Chebyshev filter design in, the radio. cheers, Jim. - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w2fca@qsl.net Sun Oct 21 13:26:48 2001 From: w2fca@qsl.net (Frank & Barb Ayers) Date: Sun, 21 Oct 2001 08:26:48 -0400 Subject: [AMPS] Oil filled cap mounting question Message-ID: <01c15a2b$a7cce080$2ddf5a41@w2fcaqsl.net> I have one of the GE energy storage caps I'm planning on using in a PS. Is there any restriction on how they are mounted? It would be a lot easier if I could mount it horizontally but wondered if there is a reason the have to be mounted up and down. Frank W2FCA -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Ian White, G3SEK" References: <6CEB3A36096CD2119FEE00A0C9410EC20260A9B6@excalibur.swindon.msl.mitel.com> Message-ID: Peter Chadwick wrote: > >Ian is doing well, and should be out of hospital on Sunday. > And is back at the keyboard - a bit achey and tottering around on crutches, but otherwise OK and glad to be home. Thanks for all the good wishes. 73 from Ian G3SEK Editor, 'The VHF/UHF DX Book' 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.com/g3sek -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ko4nrbs@yahoo.com Sun Oct 21 17:34:14 2001 From: ko4nrbs@yahoo.com (Bill Smith) Date: Sun, 21 Oct 2001 09:34:14 -0700 (PDT) Subject: [AMPS] Plate Choke Winding Message-ID: <20011021163414.60657.qmail@web20506.mail.yahoo.com> Anyone out there that rewinds Plate Chokes. My vision is not what it used to be and wanted to get a couple of old Plate Chokes rewound. 73, Bill ===== Bill Smith KO4NR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sun Oct 21 18:39:42 2001 From: 2@vc.net (2) Date: Sun, 21 Oct 2001 10:39:42 -0700 Subject: [AMPS] Plate Choke Winding Message-ID: <200110211738.f9LHcwZ14475@contesting.com> > >Anyone out there that rewinds Plate Chokes. My vision >is not what it used to be and wanted to get a couple >of old Plate Chokes rewound. Winding HV-RFCs is described in Part-4 of "Amplifiers" on my Web site. However, a dipmeter is needed. cheers, Bill - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ToddRoberts2001@aol.com Mon Oct 22 01:41:22 2001 From: ToddRoberts2001@aol.com (ToddRoberts2001@aol.com) Date: Sun, 21 Oct 2001 20:41:22 EDT Subject: [AMPS] MEASURING FILAMENT VOLTAGE Message-ID: <106.7638d22.2904c532@aol.com> I'm not sure if this has been brought up before, but wouldn't the best way to get a truly accurate reading of filament volts on a glass tube like a 4-1000 would be to solder small wires directly to the filament pins and run them to an accurately calibrated AC voltmeter? There can be a small amount of resistance where the socket grips the tube pins and in a high-current filament circuit even a small resistance can drop the filament voltage some fraction of a volt? Is it feasable to measure the filament voltage at the pins in an operating GG amplifier where the filament circuit is above ground hot with RF? I would think using a pair of small RF chokes at the pins would isolate the AC voltmeter from the RF but could they cause problems with making the circuit unstable? Has anyone ever done this? Thanks for any comments. 73 Todd Roberts WD4NGG . -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 22 01:57:00 2001 From: 2@vc.net (2) Date: Sun, 21 Oct 2001 17:57:00 -0700 Subject: [AMPS] MEASURING FILAMENT VOLTAGE Message-ID: <200110220056.f9M0uGZ22201@contesting.com> > >I'm not sure if this has been brought up before, but wouldn't the best way >to get a truly accurate reading of filament volts on a glass tube like a 4-1000 >would be to solder small wires directly to the filament pins and run them to >an accurately calibrated AC voltmeter? Soldering wires to the pins would serve no purpose since the test prods to the DMM can be applied directly to the filament pins. >There can be a small amount of >resistance where the socket grips the tube pins and in a high-current >filament circuit even a small resistance can drop the filament voltage some >fraction of a volt? True. The V-drop from the socket contact to the pin could be measured. My guess is that <50mV drop would be ok. > Is it feasable to measure the filament voltage at the >pins in an operating GG amplifier where the filament circuit is above ground >hot with RF? I would think using a pair of small RF chokes at the pins would >isolate the AC voltmeter from the RF but could they cause problems with >making the circuit unstable? Has anyone ever done this? Thanks for any >comments. The presence of RF adds virtually no useful inforation. cheers, Todd - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From kd5izi_tech@yahoo.com Mon Oct 22 02:46:02 2001 From: kd5izi_tech@yahoo.com (Randall DuCharme) Date: Sun, 21 Oct 2001 18:46:02 -0700 (PDT) Subject: [AMPS] Choke input PS question Message-ID: <20011022014602.46821.qmail@web20005.mail.yahoo.com> Greetings, I'm building another power supply for my amplifier project. I originally set out to use a capacitor input design commonly used but have since (tonight) found a large (13H) choke. I was told by the OM that I got it from that I could probably put it in the CT lead and not have to worry about any spark gap procedures. Thoughts???? I've never seen this on paper or in any book. Would the 'choking' effect be the same??? Thanks. __________________________________________________ Do You Yahoo!? Make a great connection at Yahoo! Personals. http://personals.yahoo.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From n0tt1@juno.com Sun Oct 21 12:21:39 2001 From: n0tt1@juno.com (n0tt1@juno.com) Date: Sun, 21 Oct 2001 04:21:39 -0700 Subject: [AMPS] Cleaning aluminum variable capacitors Message-ID: <20011021.042140.-461667.3.n0tt1@juno.com> Greeting gents, I bought a large variable capacitor for at a hamfest recently and the plates are somewhat corroded....something I knew about before I bought it for practically nothing. I have taken the unit apart, individual plates and all. What's the best way to clean the corrosion off the plates? 73, Charlie, N0TT ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From kc4slk@csrlink.net Mon Oct 22 04:00:26 2001 From: kc4slk@csrlink.net (Mike Sawyer) Date: Sun, 21 Oct 2001 23:00:26 -0400 Subject: [AMPS] MEASURING FILAMENT VOLTAGE References: <106.7638d22.2904c532@aol.com> Message-ID: <003201c15aa5$b4003260$c979add1@kc4slk> I have an RCA 2X 3-400Z's G-G, for 1 KW out. I was having a problem with power output. It seemed that all the power I could get out was 500 watts and that was on a good day. After some investigation, (the head banging kind), I found that the filament voltage was about 3.8 VAC!! Some one before me had apparently used 18 ga. wire to run to the RF choke. The voltage at the transformer was the 5.1 VAC which would make the 3-400's very happy. The distance between the filament transformer and the RF choke was about 18 inches. The repair was to replace the wire with 12 ga. wire that made the voltage at the filament pins, (not the RF choke), 4.8 VAC. My output went to 1 KW and has been running fine since. Mod-U-Lator, Mike(y) W3SLK I'm not sure if this has been brought up before, but wouldn't the best way to get a truly accurate reading of filament volts on a glass tube like a 4-1000 would be to solder small wires directly to the filament pins and run them to an accurately calibrated AC voltmeter? There can be a small amount of resistance where the socket grips the tube pins and in a high-current filament circuit even a small resistance can drop the filament voltage some fraction of a volt? Is it feasable to measure the filament voltage at the pins in an operating GG amplifier where the filament circuit is above ground hot with RF? I would think using a pair of small RF chokes at the pins would isolate the AC voltmeter from the RF but could they cause problems with making the circuit unstable? Has anyone ever done this? Thanks for any comments. 73 Todd Roberts WD4NGG . -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From yo9fzs@office.deck.ro Mon Oct 22 08:12:46 2001 From: yo9fzs@office.deck.ro (yo9fzs) Date: Mon, 22 Oct 2001 09:12:46 +0200 Subject: [AMPS] Use of Svetlana. 4CX800 in amp References: Message-ID: <3BD3C6EE.F1062FE2@office.deck.ro> Hello Jim A diagram for a GG 4CX800/GU74 linear is on http://krasnodar.online.ru/hamradio (russian). It may work ok as the builder say, but I think that a AB1 service will be better. At one time a russian radioamateur said he is working with a GG GU74 tube. At someone's question about low G1 dissipation he said that is not a problem since he had a box under his bed filled with such tubes. May be this is not true for you... 73, Good Luck, Traian JimMoci@aol.com wrote: > Has anyone used the Svetlana 4CX800 in grounded grid (on HF) by tying > the screen and control grid together? Is it ok to do with this tube? > There is and inexpensive and plentiful source for these tubes on E-pay > and I am giving some thought to buying a few of these tubes. > Thanks, > Jim -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Mon Oct 22 07:47:34 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Mon, 22 Oct 2001 07:47:34 +0100 Subject: [AMPS] MEASURING FILAMENT VOLTAGE Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A9DB@excalibur.swindon.msl.mitel.com> Rich said: >The presence of RF adds virtually no useful inforation. ..........but in most cases, it drives the DMM mad. Holding off the sensing with say 1Kohm resistors and suitable bypass caps and screened leads might do it, but I've been bitten a number of times by RF getting into the DMM. On one occasion, a class AB1 grounded cathode amplifier was producing full output power but the screen grid was 600 volts negative w.r.t. cathode! With no drive, it was +300. These days, I use the old fashioned Avo 8 moving coil analogue device for measurements when there's a lot of RF around. Like Rich, I doubt that measuring the filament volts with RF will provide any useful info. If you see the filament colur change as you drive the amp, maybe you need to do that. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 22 10:43:20 2001 From: 2@vc.net (2) Date: Mon, 22 Oct 2001 02:43:20 -0700 Subject: [AMPS] Choke input PS question Message-ID: <200110220942.f9M9gcZ31601@contesting.com> > >Greetings, > >I'm building another power supply for my amplifier >project. I originally set out to use a capacitor >input design commonly used but have since (tonight) >found a large (13H) choke. I was told by the OM that >I got it from that I could probably put it in the CT >lead and not have to worry about any spark gap >procedures. Choke filters work well in applications where the load current is constant - such as RTTY, AM linear and FM. With SSB, where the load current is not constant, a choke filter causes a transient V regulation problem. To observe this problem, one needs a DC 'scope. A resonant-choke filter works well for SSB. > cheers >Thoughts???? I've never seen this on paper or in any >book. Would the 'choking' effect be the same??? > >Thanks. > >__________________________________________________ >Do You Yahoo!? >Make a great connection at Yahoo! Personals. >http://personals.yahoo.com > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com > > - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Mon Oct 22 12:52:19 2001 From: philk5pc@tyler.net (Phil Clements) Date: Mon, 22 Oct 2001 06:52:19 -0500 Subject: [AMPS] MEASURING FILAMENT VOLTAGE References: <106.7638d22.2904c532@aol.com> Message-ID: <002301c15af0$01fd1a60$7b084c42@phil> During annual cleaning, inspection, and blower oiling is a good time to check the tension on the tube socket on all the pins. Yes, you will need RF chokes in line to the meter, and a way to adjust for the loss through them. I use a diode bridge, a D.C. meter, and a pot to calibrate it against a good A.C. voltmeter hooked to the tube pins. This is also a part of my annual ritual. If the socket is good, it is not necessary, IMO, to solder the meter leads to the pins. If a resistance develops between the tube pins and the socket, it should be seen on the filament voltmeter as a change from normal. (((73))) Phil, K5PC Subject: [AMPS] MEASURING FILAMENT VOLTAGE > > I'm not sure if this has been brought up before, but wouldn't the best way to > get a truly accurate reading of filament volts on a glass tube like a 4-1000 > would be to solder small wires directly to the filament pins and run them to > an accurately calibrated AC voltmeter? There can be a small amount of > resistance where the socket grips the tube pins and in a high-current > filament circuit even a small resistance can drop the filament voltage some > fraction of a volt? Is it feasable to measure the filament voltage at the > pins in an operating GG amplifier where the filament circuit is above ground > hot with RF? I would think using a pair of small RF chokes at the pins would > isolate the AC voltmeter from the RF but could they cause problems with > making the circuit unstable? Has anyone ever done this? Thanks for any > comments. 73 Todd Roberts WD4NGG . -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From philk5pc@tyler.net Mon Oct 22 13:04:19 2001 From: philk5pc@tyler.net (Phil Clements) Date: Mon, 22 Oct 2001 07:04:19 -0500 Subject: [AMPS] Choke input PS question References: <200110220942.f9M9gcZ31601@contesting.com> Message-ID: <003b01c15af1$aef51500$7b084c42@phil> > >I'm building another power supply for my amplifier > >project. I originally set out to use a capacitor > >input design commonly used but have since (tonight) > >found a large (13H) choke. I was told by the OM that > >I got it from that I could probably put it in the CT > >lead and not have to worry about any spark gap > >procedures. Back in the "olden days" it was common to see chokes installed in the B- that lacked the insulation to be placed on the B+ side. Worked just as well there, but as Rich said, you are probably not going to like the regulation on SSB. (((73))) Phil, K5PC -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From phil@vaxxine.com Mon Oct 22 14:00:12 2001 From: phil@vaxxine.com (Phil (VA3UX)) Date: Mon, 22 Oct 2001 09:00:12 -0400 Subject: [AMPS] Cleaning aluminum variable capacitors In-Reply-To: <20011021.042140.-461667.3.n0tt1@juno.com> Message-ID: <5.0.2.1.0.20011022085520.009ee6b0@vaxxine.com> At 04:21 AM 10/21/2001 -0700, n0tt1@juno.com wrote: >Greeting gents, > >I bought a large variable capacitor for at a hamfest recently and >the plates are somewhat corroded....something I knew about >before I bought it for practically nothing. I have taken >the unit apart, individual plates and all. > >What's the best way to clean the corrosion off the plates? I use a loose-knit buffing wheel on a motor to do this. It's a bit of work but after buffing every plate and part, the result was a mirror finish. I lightly loaded the buffing wheel with a whitish buffing compound that comes in a solid bar. After buffing I washed all the parts in Varsol (mineral spirits, paint thinner). Phil >73, >Charlie, N0TT > > >________________________________________________________________ >GET INTERNET ACCESS FROM JUNO! >Juno offers FREE or PREMIUM Internet access for less! >Join Juno today! For your FREE software, visit: >http://dl.www.juno.com/get/web/. > >-- >FAQ on WWW: http://www.contesting.com/FAQ/amps >Submissions: amps@contesting.com >Administrative requests: amps-REQUEST@contesting.com >Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Mon Oct 22 13:57:04 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Mon, 22 Oct 2001 13:57:04 +0100 Subject: [AMPS] Cleaning aluminum variable capacitors Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A9ED@excalibur.swindon.msl.mitel.com> A caustic soda bath works, too. About 3 ounces of soda to 1.5 pints of hot water. Quick scrub with a wire brush first. To remove the black deposit afterwards, dip in dilute (15%) nitric acid. Or drop in vinegar and give a rub over with a pan scrubber. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k7fm@teleport.com Mon Oct 22 14:20:20 2001 From: k7fm@teleport.com (Lamb) Date: Mon, 22 Oct 2001 06:20:20 -0700 Subject: [AMPS] Choke input PS question References: <200110220942.f9M9gcZ31601@contesting.com> Message-ID: <001c01c15afc$55832100$b73c1ad8@colinlam> When using a large filter choke in my hv power supply, I experienced 2 problems. First, the collapsing field blew the diodes out. Second, there were resonances that caused problems at certain current. The only reason for using the choke in the first place was because the voltage output of my transformer was higher than I wanted and the choke was available. Finally solved problem by shunting the choke with a large resistor to de-Q the choke. Worked ok. But, the next amplifier was not built in a 6 foot rack and the choke went away. Colin, K7FM -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Mon Oct 22 14:30:33 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Mon, 22 Oct 2001 14:30:33 +0100 Subject: [AMPS] Choke input PS question Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A9EE@excalibur.swindon.msl.mitel.com> I've used negative lead filtering and tuned choke input very successfully. By using the RIGHT value of capacitor, you can get quite good regulation - in conjunction with a suitable bleeder, of course. The capacitors need to be fairly hefty types capable of carrying a fair bit of current - I use some WW2 paper caps, about 4 inches wide by 2 inches deep by 6 inches high, rated 0.1uF at 5kV DC, with big ceramic standoff terminals on them. The correct values were determined empirically, using a variac on the primary, and a number of 100 watt wirewound resistors as a varying load. Switch OFF before changing load, of course. You could use a string of series light bulbs, or couple of high dissipation tubes as varying loads. One thing you do not want is to get the choke resonant. The idea of the capacitor is to get the choke on the HF side of resonance, but where it looks like a very much bigger inductance than it is. That's at the minimum current drain: as the current goes up and the choke inductance goes down, it tunes further HF, but the critical value of inductance that's required goes down, so it doesn't matter. The other thing I do is to use a large (50 microfarad) capacitor on the output to give good dynamic regulation. (actually a string of computer grade electrolytics). The equalising resistors are well under run, and placed ABOVE the capacitors, which are at the very bottom of the cabinet: the big bleeder resistance and the glitch resistance (50 ohm w/w, 100 watts, 1.5 inch diameter, 12 inches long) and diodes are above them, so the caps are as cool as practical. In practice, they feel to be at about ambient temp even after a long period. Note this is not a small power supply.................18 inches wide, 20 inches deep in the bottom of the 5 foot high 19 inch rack that has the amplifier in it. I've used equalising resistors on the diodes to, despite what people say. Next one will use K2AW blocks.... Bear in mind Tom Rauch's tale of tuned choke filters and learn from that........I'd suggest it's an area where if you're not extremely sure of what you're doing, DON'T! 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From kd5izi_tech@yahoo.com Mon Oct 22 14:43:45 2001 From: kd5izi_tech@yahoo.com (Randall DuCharme) Date: Mon, 22 Oct 2001 06:43:45 -0700 (PDT) Subject: [AMPS] Choke input PS question Message-ID: <20011022134345.2910.qmail@web20010.mail.yahoo.com> Interesting, And here I thought that the primary reason many modern amplifiers lacked heavy chokes was to save weight, space, and cost. :-) Something like this would have never occured to me. It's surely not mentioned in any of the (albeit meager supply) literature I have on hand. What would be the symptom(s) of this problem? What would it look like on a scope? Ringing?? Resonant-choke filter? I'm not 100% sure I understand what you mean.... but I'm guessing that you're meaning resonance with respect to the ripple?? Would you be willing to elaborate a little bit please? Many thanks. RD --- 2 <2@vc.net> wrote: > Choke filters work well in applications where the > load current is > constant - such as RTTY, AM linear and FM. With > SSB, where the load > current is not constant, a choke filter causes a > transient V regulation > problem. To observe this problem, one needs a DC > 'scope. A > resonant-choke filter works well for SSB. > > > cheers > > - R. L. Measures, 805.386.3734,AG6K, > www.vcnet.com/measures. > end > __________________________________________________ Do You Yahoo!? Make a great connection at Yahoo! Personals. http://personals.yahoo.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Mon Oct 22 14:49:40 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Mon, 22 Oct 2001 14:49:40 +0100 Subject: [AMPS] Choke input PS question Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A9F1@excalibur.swindon.msl.mitel.com> Randall said: >Resonant-choke filter? I'm not 100% sure I understand >what you mean.... but I'm guessing that you're meaning >resonance with respect to the ripple?? As I said in my previous, you don't actually resonate the choke. A parallel tuned circuit looks like a pure resistance at resonance. That's using the definition of resonance that applied voltage and curent are in phase: the approximation used at RF that XL = XC won't do here, because you can't neglect the choke resistance. As you go higher in frequency from resonance, the inductive reacatance increase and the capacitive reactance decreases, so capacity wins and the circuit looks capacitive. Below resonance, the effect is the other way round. A long way below resonance, the choke has it nominal inductance; as resonance is neared coming from LF, the choke starts looking bigger and bigger. This means that amount of physical there choke inductance needed to achieve critical inductance is less. Critical inductance is that required such that the current flow in the choke is constant over the cycle. So a 'tuned' choke for a 50Hz system with a full wave bridge (100Hz ripple) would be less use than teats on a bull in a 60Hz system......so the system isn't a good choice if you can't be fairly certain of supply frequency stability. If you get the choke resonant, you can get enormous voltages built up by the resonance, with all sorts of problems. Hope this helps. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 22 16:04:56 2001 From: 2@vc.net (2) Date: Mon, 22 Oct 2001 08:04:56 -0700 Subject: [AMPS] Choke input PS question Message-ID: <200110221504.f9MF4AZ05747@contesting.com> > >Randall said: > >>Resonant-choke filter? I'm not 100% sure I understand >>what you mean.... but I'm guessing that you're meaning >>resonance with respect to the ripple?? > > >As I said in my previous, you don't actually resonate the choke. > Do Not resonate the choke (at 2x the mains frequency with a parallel C) if you require poor transient V-regulation. > ... - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From kd5izi_tech@yahoo.com Mon Oct 22 16:07:55 2001 From: kd5izi_tech@yahoo.com (Randall DuCharme) Date: Mon, 22 Oct 2001 08:07:55 -0700 (PDT) Subject: [AMPS] Choke input PS question In-Reply-To: <6CEB3A36096CD2119FEE00A0C9410EC20260A9F1@excalibur.swindon.msl.mitel.com> Message-ID: <20011022150755.37548.qmail@web20009.mail.yahoo.com> Thanks Peter, --- Peter Chadwick wrote: > > Randall said: > > >Resonant-choke filter? I'm not 100% sure I > understand > >what you mean.... but I'm guessing that you're > meaning > >resonance with respect to the ripple?? > > > As I said in my previous, you don't actually > resonate the choke. Sorry.... I hadn't gotten that email yet when I sent the above question(s). It did explain that fairly well. I'm searching the archives to see if I can find Mr. Rauch's tale that you mentioned... as well as any other info on the subject. Looks as though there's quite a bit of info in them. Should have probably searched them before posting. Nonetheless, thanks for your time and thoughts. Greatly appreciated! RD __________________________________________________ Do You Yahoo!? Make a great connection at Yahoo! Personals. http://personals.yahoo.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Mon Oct 22 15:59:29 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Mon, 22 Oct 2001 15:59:29 +0100 Subject: [AMPS] Choke input PS question Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A9F3@excalibur.swindon.msl.mitel.com> Rich says: >Do Not resonate the choke (at 2x the mains frequency with a parallel C) >if you require poor transient V-regulation. I'd say DON'T do it anyway. Of course Rich, you realise that you can't use a 3-500z as a variable load when testing the system, as 100 or 120Hz is below its cut off frequency!!!!!!! 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k7fm@teleport.com Mon Oct 22 16:19:53 2001 From: k7fm@teleport.com (Colin Lamb) Date: Mon, 22 Oct 2001 08:19:53 -0700 Subject: [AMPS] Choke input PS question References: <200110221504.f9MF4AZ05747@contesting.com> Message-ID: <001001c15b0d$19be7820$62031ad8@k7fm> Rich: The adverse qualities of the power supply choke can be alleviated by shunting it with some nichrome wire. 73, Colin K7FM -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Mon Oct 22 16:19:06 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Mon, 22 Oct 2001 16:19:06 +0100 Subject: [AMPS] Choke input PS question Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A9F4@excalibur.swindon.msl.mitel.com> Colin said: >The adverse qualities of the power supply choke can be alleviated by >shunting it with some nichrome wire. But you mustn't use too much nichrome wire....... 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Mon Oct 22 16:28:12 2001 From: W8JI@contesting.com (Tom Rauch) Date: Mon, 22 Oct 2001 11:28:12 -0400 Subject: [AMPS] MEASURING FILAMENT VOLTAGE In-Reply-To: <106.7638d22.2904c532@aol.com> Message-ID: <3BD402CC.32752.27F7A806@localhost> > I'm not sure if this has been brought up before, but wouldn't the best > way to get a truly accurate reading of filament volts on a glass tube > like a 4-1000 would be to solder small wires directly to the filament > pins and run them to an accurately calibrated AC voltmeter? Normally you can just measure at the socket pins, if the socket has noticeable drop you need to change it or repair it anyway. If you want to temporarily measure at the pins, pull the tube. Use teflon wire-wrap wire like from Radio Shack, and wrap a stripped end tightly around the pins at the tube base end of the pins. Plug the tube back in, measure voltage with an accurate high impedance AC voltmeter, so there is almost no current through the wire wrapped around each filament pin. If you want to measure with drive, add a couple 200 uH or larger chokes near the pins and some temporary bypass capacitors on the meter side of the chokes. 2.5mH chokes are good for VLF amplifiers. For 1.8-30 MHz amplifiers, use a few hundred uH. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From W8JI@contesting.com Mon Oct 22 16:28:11 2001 From: W8JI@contesting.com (Tom Rauch) Date: Mon, 22 Oct 2001 11:28:11 -0400 Subject: [AMPS] Cleaning aluminum variable capacitors In-Reply-To: <20011021.042140.-461667.3.n0tt1@juno.com> Message-ID: <3BD402CB.6596.27F7A5E8@localhost> > I bought a large variable capacitor for at a hamfest recently and the > plates are somewhat corroded....something I knew about before I bought > it for practically nothing. I have taken the unit apart, individual > plates and all. > > What's the best way to clean the corrosion off the plates? Clean it any way that does not leave any sharp points or scratched edges on the capacitor plate. Any sharp edge (even very very fine or small edges), burrs, or reduction of rounding of plate edges greatly reduces voltage breakdown. Capacitor plates in the USA capacitor manufacturing facilities are normally tumbled for hours in a solution containing walnut shells to micro-polish the plates and round the edges. 73, Tom W8JI W8JI@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 22 16:35:29 2001 From: 2@vc.net (2) Date: Mon, 22 Oct 2001 08:35:29 -0700 Subject: [AMPS] Choke input PS question Message-ID: <200110221534.f9MFYjZ07426@contesting.com> > >Interesting, > >And here I thought that the primary reason many modern >amplifiers lacked heavy chokes was to save weight, >space, and cost. :-) Something like this would have >never occured to me. It's surely not mentioned in any >of the (albeit meager supply) literature I have on >hand. > >What would be the symptom(s) of this problem? What >would it look like on a scope? Ringing?? > Not quite. When an old timer (W6SDM) told me about the unresonant choke problem, he explained that the transient regulation problem can't be seen on a garden-variety voltmeter because the needle inertia is too high. Sure enough, I saw no problem on the voltmeter. The voltage regulation looked good. However, with an oscilloscope, when I connected the load, the output V briefly spiked downward around 50%. When I disconnected the load, the output spiked upward about 50%. I was impressed. >... - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 22 16:45:07 2001 From: 2@vc.net (2) Date: Mon, 22 Oct 2001 08:45:07 -0700 Subject: [AMPS] MEASURING FILAMENT VOLTAGE Message-ID: <200110221544.f9MFiLZ07871@contesting.com> > >> I'm not sure if this has been brought up before, but wouldn't the best >> way to get a truly accurate reading of filament volts on a glass tube >> like a 4-1000 would be to solder small wires directly to the filament >> pins and run them to an accurately calibrated AC voltmeter? > >Normally you can just measure at the socket pins, if the socket >has noticeable drop you need to change it or repair it anyway. > >If you want to temporarily measure at the pins, pull the tube. Use >teflon wire-wrap wire like from Radio Shack, and wrap a stripped >end tightly around the pins at the tube base end of the pins. > ... ... // Wire-wrap wire is designed to work with wire-wrap terminals, which are square, The sharp corners of the square terminal pierces the insulation and contacts the conductor. If the tube's pins are square, Mr. Rauch's suggestion should work well. cheers - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Mon Oct 22 16:39:19 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Mon, 22 Oct 2001 16:39:19 +0100 Subject: [AMPS] Choke input PS question Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260A9F6@excalibur.swindon.msl.mitel.com> Rich said; >However, with an oscilloscope, when I connected the load, >the output V briefly spiked downward around 50%. When I disconnected the >load, the output spiked upward about 50%. I'm not sure if that happens with a tuned choke (I don't like calling it 'resonant' because we've seen it had better not be!) but those spikes are why you need a good big capacitor on the output to keep the dynamic regulation. One reason that you can see the technique used in big (5kW and up) commercial tx's with relatively small capacitors (10 to 20 uF) is that most of those run ISB type services, frequently with multi channel type teleprinter signals on the other sideband: this significantly reduces the percentage plate current change and reduces the significance of the effect. G2DAF wrote about the problem over 40 years ago, and in the design of the G2DAF linear (?), he didn't use a smoothing choke. However, he did use 866 rectifiers with capacitor input, and enough capacity that he was pushing the peak current ratings of those tubes. Now whether or not that was symptomatic of Dick's design approach, I leave you to judge. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jtml@lanl.gov Mon Oct 22 19:56:08 2001 From: jtml@lanl.gov (John T. M. Lyles) Date: Mon, 22 Oct 2001 12:56:08 -0600 Subject: [AMPS] metering (filament V) Message-ID: I would use small wires that can easily blow open (should you accidentally have a short on them later) or have small fuses with them. Filament voltage is typically measured at the socket pins unless there is NO socket, in which case the flanges on the tube are even better. If the pins are loose, then you should fix it. Using 50 mV or so drop as Rich says is probably good. In our systems, we try to measure the filament with RF off, due to the susceptability of many 'true rms' digital meters to interference. Iron Vane meters are real nice. You can also use a lot of RF bypassing and choking on the wires, but its up to you. Even having a couple of pin jacks on the panel is enough, to stick a good meter on occasionally. Now for GG operation, it will be tricky. I would suggest sticking a meter inside the deck somewhere where you can observe it through a screen. If that sounds tacky, then at least be very careful about your hookup, use the chokes that you mention, and watch for being a source of RFI though the meter hole. In one particular cathode follower amplifier here, we have the meter on the AC primary to the fil transformer, and made a calibration, checking the actual filament AC at the tube, with RF and HV off. Then marked the AC meter or put a scaling factor in the logbook. This is certainly the easiest way for a GG or CF amplifier. John K5PRO > >I'm not sure if this has been brought up before, but wouldn't the best way to >get a truly accurate reading of filament volts on a glass tube like a 4-1000 >would be to solder small wires directly to the filament pins and run them to >an accurately calibrated AC voltmeter? There can be a small amount of >resistance where the socket grips the tube pins and in a high-current >filament circuit even a small resistance can drop the filament voltage some >fraction of a volt? Is it feasable to measure the filament voltage at the >pins in an operating GG amplifier where the filament circuit is above ground >hot with RF? I would think using a pair of small RF chokes at the pins would >isolate the AC voltmeter from the RF but could they cause problems with >making the circuit unstable? Has anyone ever done this? Thanks for any >comments. 73 Todd Roberts WD4NGG . -- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 22 20:00:14 2001 From: 2@vc.net (2) Date: Mon, 22 Oct 2001 12:00:14 -0700 Subject: [AMPS] Choke input PS question Message-ID: <200110221859.f9MIxRZ12603@contesting.com> > >Rich: > >The adverse qualities of the power supply choke can be alleviated by >shunting it with some nichrome wire. > Indeed - like about 5cm of #18 - which has c. 50milli-ohms. However, shorting the choke with #18 copper might work a bit better for 8281 supplies since it 50x more conductive. On the other hand, resonating the choke would be preferable unless one is in need of more voltage and/or a boat anchor. cheers, Colin - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 22 20:00:16 2001 From: 2@vc.net (2) Date: Mon, 22 Oct 2001 12:00:16 -0700 Subject: [AMPS] Choke input PS question Message-ID: <200110221859.f9MIxTZ12607@contesting.com> > >Rich says: > >>Do Not resonate the choke (at 2x the mains frequency with a parallel C) >>if you require poor transient V-regulation. > > >I'd say DON'T do it anyway. > >Of course Rich, you realise that you can't use a 3-500z as a variable load >when >testing the system, as 100 or 120Hz is below its cut off frequency!!!!!!! > chortle > cheerio, Peter - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 22 20:00:17 2001 From: 2@vc.net (2) Date: Mon, 22 Oct 2001 12:00:17 -0700 Subject: [AMPS] Choke input PS question Message-ID: <200110221859.f9MIxUZ12611@contesting.com> > >Rich said; > >>However, with an oscilloscope, when I connected the load, >>the output V briefly spiked downward around 50%. When I disconnected the >>load, the output spiked upward about 50%. > >I'm not sure if that happens with a tuned choke It doesn't. This is why Collins, Henry, Hughes, Continental, on and on use resonant choke filters. >(I don't like calling it >'resonant' because we've seen it had better not be!) but those spikes are why >you need a good big capacitor on the output to keep the dynamic regulation. > A capacitor on the output would have to humongous to correct this problem. Resonating capacitors are typically 0.1uF to 0.2uF at c. 2.5x the DCV out.. The resonance point is typically c. 2.45x the electric mains frequency. >One reason that you can see the technique used in big (5kW and up) commercial >tx's with relatively small capacitors (10 to 20 uF) is that most of those run >ISB type services, frequently with multi channel type teleprinter signals >on the >other sideband: this significantly reduces the percentage plate current >change >and reduces the significance of the effect. > >G2DAF wrote about the problem over 40 years ago, and in the design of the >G2DAF >linear (?), he didn't use a smoothing choke. However, he did use 866 >rectifiers with capacitor input, and enough capacity that he was pushing the peak >current ratings of those tubes. Exceeding the peak current rating is more like it. >Now whether or not that was symptomatic of Dick's >design approach, I leave you to judge. > No surprise. > cheers, Peter - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From g8gsq@qsl.net Mon Oct 22 20:24:38 2001 From: g8gsq@qsl.net (Steve Thompson) Date: Mon, 22 Oct 2001 20:24:38 +0100 Subject: [AMPS] metering (filament V) Message-ID: <001601c15b2f$3254e6e0$e70d7ad5@office> -----Original Message----- From: John T. M. Lyles To: amps@contesting.com Date: 22 October 2001 20:03 Subject: [AMPS] metering (filament V) > >I would use small wires that can easily blow open (should you >accidentally have a short on them later) or have small fuses with >them. A couple of 1k resistors avoids the need for replacing fuses. Error's minimal provided you use a hiZ meter like a DVM, accepting all the caveats about waveform and no rf that come with it. Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From n0tt1@juno.com Mon Oct 22 13:00:04 2001 From: n0tt1@juno.com (n0tt1@juno.com) Date: Mon, 22 Oct 2001 05:00:04 -0700 Subject: [AMPS] Cleaning aluminum variable capacitors Message-ID: <20011022.050005.-397397.1.n0tt1@juno.com> Greetings gents! Many thanks to those who commented about cleaning variable capacitor plates. Upon closer inspection, the plates are pitted...looks like a moonscape up close. So per the many suggestions, I will first mechanically remove the edges of the "craters", probably with a very fine sandpaper with and oil or water, then polish all the plates with some of the "blue stuff" cleaner using a low speed "cotton wheel"....and avoid creating any sharp edges on the plates in the process. (BTW, if one were to try this too, wear a face mask to filter out the cotton fibers.) One very interesting bit of info was received on how USA manufacturers polish the plates and round the edges by using a mixture of walnut shells in a tumbler. Now if a guy had a jeweller's "rock tumbler" and the right polishing compound (like some crushed walnut shells) that would be interesting to try! Gees, we hams do a lot of work just to "save" a few bucks! hi hi 73, Charlie, N0TT On Sun, 21 Oct 2001 04:21:39 -0700 n0tt1@juno.com writes: > > Greeting gents, > > I bought a large variable capacitor for at a hamfest recently and > the plates are somewhat corroded....something I knew about > before I bought it for practically nothing. I have taken > the unit apart, individual plates and all. > > What's the best way to clean the corrosion off the plates? > > 73, > Charlie, N0TT ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jtml@lanl.gov Tue Oct 23 16:17:03 2001 From: jtml@lanl.gov (John T. M. Lyles) Date: Tue, 23 Oct 2001 09:17:03 -0600 Subject: [AMPS] resonant choke PS In-Reply-To: <200110230345.f9N3jYZ24747@contesting.com> References: <200110230345.f9N3jYZ24747@contesting.com> Message-ID: The resonant choke (L input filter) for power supplies can indeed operate at resonance, with a parallel capacitor that is rated for the 'tank' current and voltage. If the choke is tapped (as i had them manufactured by SNC for the Broadcast Electronics FM-3.5A and B series transmitters - circa 1984) it can be for 50 or 60 Hz. The resonator works at the ripple frequency for the single phase supply, and it needs to be chosen to work when the choke L is at maximum. This is when the DC current is low, i.e., for SSB during idle time. Choke inductance will decrease as DC current increases. You can measure this with a DC supply and an inductance meter or bridge. I suppose you would want a 'stiff' choke for a resonant choke system, not a swinging choke. Otherwise it will be fighting your network. Bleeder current alone and tube AB1 or B idling current being the only load at the one end of the curve. At the heavy load times, a standard choke is adequate to keep constant current flowing throughout the rectification cycle. Check the critical inductance calculations in any handbook and see that it depends on the load current. Thats why old fashioned L input supplies had big bleeders as well. Better regulation. If the current is discontinuous over the cycle, the filter cap will charge up to peak, and the power supply soars. This is horrible regulation, no load to full load. I would recommend that any resonant choke system be followed with a second LC smoothing filter, it can be relatively small such as a few Hy and uF. Or the filter cap should be chosen larger. Calculate what sort of ripple suppression you need and work through Ohms law for the AC ripple. Check the harmonics up to mid audio band. You may be suprised at how bad it can be, if above the ripple frequency. Remember that the resonator is only working on the 100 and 120 Hz, and it passes the higher frequencies with ease to the load. A few weeks ago I spoke with a broadcaster who had one of the rigs I mentioned above. He told me that he was horrified to see the plate meter pegging when he removed the exciter drive to the PA. It dawned on me that the capacitor had been there since 1984, and was probably leaky or changing value. I recommended replacing the 0.97 uF polypropylene 2500 VAC capacitors. Two are used in series as the C across the choke. That was it. Hint>>> you can get HVAC polypropylene capacitors as replacement parts for the voltage doubler for microwave ovens. They are oil filled as in old filter caps and motor start caps, but they can handle the high circulating current and ripple v across them. The old timer at SNC who developed my choke told me that Heathkit or Johnson had tried to use a standard oil/paper cap in the 1960s and had reliability problems. 73 John K5PRO -- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Tue Oct 23 16:13:34 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Tue, 23 Oct 2001 16:13:34 +0100 Subject: [AMPS] resonant choke PS Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260AA0D@excalibur.swindon.msl.mitel.com> John said: >The resonant choke (L input filter) for power supplies can indeed >operate at resonance What happens to the PIV on the rectifiers? One would expect the high voltage caused by the resonance to push them hard. Puzzled 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jtml@lanl.gov Tue Oct 23 16:45:09 2001 From: jtml@lanl.gov (John T. M. Lyles) Date: Tue, 23 Oct 2001 09:45:09 -0600 Subject: [AMPS] more on resonant choke PS Message-ID: PIV at the rectifer was rated after measuring the voltage across the choke, with two HV probes and a differential measurement. I remember that it was about 2500 VAC, so thats why I had to use two caps. It was, of course, sitting at high DC as well. It was near resonance, as evident by very good regulation, load to no load (bleeder only). The Q of the circuit was limited by the resistance of the choke and the capacitors themselves I suppose. I would have to dig back through papers to find the measurements, but it had a bandwidth of a few Hz, probably simulated some AC with a power amplifier and generator to drive it while biasing with some DC current. With a few Hz, out of 60, thats 30. Maybe it was less, I cannot remember. The point is, this thing was not really driving to very high voltage, and sat at 2500 VAC worst case, for a 4500 VDC 1.1 Amp DC supply. So I had 12 - 15 kV PRV diodes. This was over 15 years ago. But I would say hundreds of the rigs were sold over 10 years, with this ciruit in them. I did it not so much for dynamic regulation (class C FM - who cares!), but so that the no load to full load reg was good (when folks would kill the driver stage, i hated transmitters where the meter pegs off scale), and for lower stored energy with still good filtering. It was a two section LC filter with the first L resonant. Nothing over 6 Hy and 4 uF for capacitors. John -- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From tmartin@chartermi.net Tue Oct 23 17:08:21 2001 From: tmartin@chartermi.net (Tom Martin) Date: Tue, 23 Oct 2001 11:08:21 -0500 Subject: [AMPS] ground loop? Message-ID: <3BD595F5.B76F20E3@chartermi.net> This is a puzzling situation here in the shack. I have a 117 volt receptacle that shows a voltage reading of 117 when I measure between the ground hole and hot water register in the room. Obviously, this is a dangerous situation. When I checked out the receptacle, I found that there wasn't any ground wire connected to the box(old wiring, new 3 prong receptacle added by previous owner). I ran a ground to a cold water pipe nearby and voltage between ground and radiator disappeared. I was happy with my success until I turned out a lamp that was on in the shack and the breaker popped. I removed the new ground wire and reset the breaker and now we're back to where we started. Any suggestions? Tom W8JWN -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 24 01:54:14 2001 From: 2@vc.net (2) Date: Tue, 23 Oct 2001 17:54:14 -0700 Subject: [AMPS] ground loop? Message-ID: <200110240053.f9O0rOZ13375@contesting.com> > >This is a puzzling situation here in the shack. I have a 117 volt >receptacle that shows a voltage reading of 117 when I measure between >the ground hole and hot water register in the room. Obviously, this is >a dangerous situation. >When I checked out the receptacle, I found that there wasn't any ground >wire connected to the box(old wiring, new 3 prong receptacle added by >previous owner). I ran a ground to a cold water pipe nearby and voltage >between ground and radiator disappeared. I was happy with my success >until I turned out a lamp that was on in the shack and the breaker >popped. I removed the new ground wire and reset the breaker and now >we're back to where we started. Any suggestions? > // The white wire is usually the neutral. All of the neutral wires connect back to the ground of the breaker box. You can confirm this by measuring the potential to a ground. Although it's not according to code, when no ground wire is available, connecting the outlet's ground terminal to the neutral terminal holds the ground to no more than a few volts max. above gnd. cheers - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From dcoolica@planet.eon.net Wed Oct 24 01:56:33 2001 From: dcoolica@planet.eon.net (Denis Coolican) Date: Tue, 23 Oct 2001 19:56:33 -0500 Subject: [AMPS] Heath HM 2140 PEP power meter Message-ID: <3BD611C1.D4428E74@planet.eon.net> I was wondering what the process was for calibrating the Heath HM 2140 power meter for pep reading. I see 4 controls in the box. I have a reference Bird but I am missing the instructions on how to calibrate the Heathkit box. Can anyone help a little! Denis VE6AQ -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From nospam4me@juno.com Wed Oct 24 03:47:12 2001 From: nospam4me@juno.com (skipp isaham) Date: Tue, 23 Oct 2001 19:47:12 -0700 Subject: [AMPS] A Clone of an SB-220 by SBE Message-ID: <20011023.194733.-293603.1.nospam4me@juno.com> re: clone of an SB-220 by SBE - Hello again, - An interesting sale now on Ebay... I ran across a clone of an SB-220, made by SBE. Don't know if this model is a production unit, the below URL will give you a good view. - http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=1287426542 - item number 1287426542 - I have no association with the auction, but I thought the clone job was pretty neat to look at so I'll mention it here. SBE was south of San Francisco and no longer does radio gear. - cheers skipp ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From nospam4me@juno.com Wed Oct 24 03:38:25 2001 From: nospam4me@juno.com (skipp isaham) Date: Tue, 23 Oct 2001 19:38:25 -0700 Subject: Fw: [AMPS] Heath HM 2140 PEP power meter Message-ID: <20011023.194733.-293603.0.nospam4me@juno.com> Hi Dennis, - If the http://bama.sbc.edu web page doesn't have the paperwork for your watt meter, drop me an Email. I've spent the last three weeks resorting my twice moved file cabinets and things are back in a semi usable order. I probably have a copy of the manual or one very similar in my files. - the above URL is the "boat anchor manual archive." cheers skipp - --------- Forwarded message ---------- From: Denis Coolican I was wondering what the process was for calibrating the Heath HM 2140 power meter for pep reading. I see 4 controls in the box. I have a reference Bird but I am missing the instructions on how to calibrate the Heathkit box. Can anyone help a little! Denis VE6AQ ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 24 11:32:26 2001 From: 2@vc.net (2) Date: Wed, 24 Oct 2001 03:32:26 -0700 Subject: [AMPS] RE: 8k ultra/ "tuned input" Message-ID: <200110241031.f9OAVZZ23592@contesting.com> Since Jim's reply involves issues that are likely to be of widespread interest, I am posting my reply to the group. > >-----Original Message----- >From: 2@vc.net [mailto:2@vc.net] >Sent: Thursday, October 18, 2001 19:08 >To: Jim Thomson >Subject: RE: 8k ultra/ "tuned input" >> >>Everything else in that amp would have 8500v on it as >>well, like their glitch R in neg lead, plate block caps, by pass >>caps, all wiring etc. Besides 300w of bleeder resistor heat is >>a bit much. Better to go to a simple hypersil c core setup, >>with a huge Cap. IE: cap input filter. Better to put the weight >>and expense of an unneeded choke into a better plate xfmr in the >>1st place. Reg is the same, and ripple is zip with >50uf. >> >For RTTY and AM, the resonant choke filter is the E-ticket. > >#### On rtty/am/fm, who cares? // Your Emailer's attribution marks are not correct. > Reg is perfect, cuz u are in >a steady state plate current senario. // Regulation is not the reason for using a resonant-choke filter. With a capacitor filter, the peak current is c. 10x higher on the electric mains, so one must compensate by using heavier gauge wiring to the circuit-breaker box. The "Plywood Box" amplifier needed #4ga. Cu to maintain acceptable HV regulation. When tuning up the PB with a tuning pulser, the wiring could be heard making a racket in the attic -- and the neighbor's porchlight would blink at the tune-up pulse rate. >###### resonant choke filters are a dead loss. Commercial >stations use em for one reason only, and that's to eliminate >high surge currents through the diode strings, when supply is a >single phase type. // The Collins Radio 208-U10 amplifier uses 3-phase 50/60 Hz power. It has a resonant-choke filter. >- Resonant choke supplies don't need huge output caps, as the >resonant choke setup kills the ripple. > >-the ripple with 3 phase supplies is only c 5% percent, and >that's the un-filtered dc output (vs 48-50%, ripple on a single >phase supply). // As I see it, with an unfiltered, single-phase DC supply, the instantaneous output potential varies from c. 1.4x the RMS V to 0V. Is this not 100% ripple? >To get from 5% ripple down to <1% is a piece o >cake with a simple cap input filter + a 3 phase diode/plate >xfmr setup. > >- like John Lyles sez... you need extra LC sections thrown in >just to get rid of the harmonics of the 120hz ripple, like >240, 360 hz etc. The resonant choke only kills the 120hz >ripple and not the harmonics. // I have heard a number of signals from 1500w amplifiers that used a resonant-choke/shunt C filter without an additional harmonic filter. I have not yet heard any ripple harmonics. >More L/C sections or a big >output cap, in which case, you may as well just deep- six the >resonant choke, and stick in a huge cap. // The aforementioned amplifiers used c. 10uF of shunt filtering after the resonant-choke. > Then both static and >dynamic reg is excellent, and no ripple or harmonics of ripple >freq. > >-IE: hpersil pole pig + >50uf cap.....end of story. 6A >diodes are cheap > // #4-gauge Cu wire is hardly cheap. cheers, Jim VE7RF - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From doug@nc.rr.com Wed Oct 24 15:02:36 2001 From: doug@nc.rr.com (Doug Hall) Date: Wed, 24 Oct 2001 10:02:36 -0400 Subject: [AMPS] A Clone of an SB-220 by SBE In-Reply-To: <20011023.194733.-293603.1.nospam4me@juno.com> Message-ID: > -----Original Message----- > From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On > Behalf Of skipp isaham > Sent: Tuesday, October 23, 2001 10:47 PM > To: amps@contesting.com > Subject: [AMPS] A Clone of an SB-220 by SBE > An interesting sale now on Ebay... I ran across > a clone of an SB-220, made by SBE. Don't know if this > model is a production unit, the below URL will give you > a good view. > - > http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=1287426542 > - Looking at the pictures gives me the impression that this amp does not use the same split-chassis cooling method found in the SB-220. It might, but it's not obvious from the photos. Does anyone know? Doug, K4DSP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Wed Oct 24 15:26:06 2001 From: stevek@jmr.com (Steve Katz) Date: Wed, 24 Oct 2001 07:26:06 -0700 Subject: [AMPS] A Clone of an SB-220 by SBE Message-ID: I don't know, but I'd love to hear if anyone knows about this "SBE." The only SBE I remember is (was) SideBand Engineers, in Goleta, CA -- which is *really* far south of San Francisco, like 300 miles (it's adjacent to Santa Barbara), and they've been gone for many, many years... Maybe there's "another" SBE? WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: Doug Hall [SMTP:doug@nc.rr.com] > Sent: Wednesday, October 24, 2001 7:03 AM > To: amps@contesting.com > Subject: RE: [AMPS] A Clone of an SB-220 by SBE > > > > > > -----Original Message----- > > From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On > > Behalf Of skipp isaham > > Sent: Tuesday, October 23, 2001 10:47 PM > > To: amps@contesting.com > > Subject: [AMPS] A Clone of an SB-220 by SBE > > > An interesting sale now on Ebay... I ran across > > a clone of an SB-220, made by SBE. Don't know if this > > model is a production unit, the below URL will give you > > a good view. > > - > > http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=1287426542 > > - > > > Looking at the pictures gives me the impression that this amp does not use > the same split-chassis cooling method found in the SB-220. It might, but > it's not obvious from the photos. Does anyone know? > > Doug, K4DSP > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From tmartin@chartermi.net Wed Oct 24 16:02:26 2001 From: tmartin@chartermi.net (Tom Martin) Date: Wed, 24 Oct 2001 10:02:26 -0500 Subject: [AMPS] Ground loop Message-ID: <3BD6D801.CE3A753D@chartermi.net> Thanks to all that offered suggestions. The electrician just left and the problem is solved. There were two reasons for the problem. First, a 3-way switch was used instead of a 2-way and it was wired incorrectly. The ground wire was connected to the traveler lug instead of the green ground lug which wasn't even on the switch. Also, all of the ground wires on several receptacles and overhead lights on the circuit were just wrapped around the Romex and not connected. One thing nice about living in a small town in the U.P. and being a retired teacher is that former students own electrical companies and respond quickly. 73, Tom -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Jim" Message-ID: <000b01c15ca1$592e9680$c4efbfa8@jims> If you are talking about the box that has the input and output connectors on it ? The Heathkit manual dutifully says "do not adjust these pots!" There are several pots inside of the meter itself for calibration. Check your manual. 73 Jim W7RY ----- Original Message ----- From: "Denis Coolican" To: Sent: Tuesday, October 23, 2001 5:56 PM Subject: [AMPS] Heath HM 2140 PEP power meter > > I was wondering what the process was for calibrating the Heath HM 2140 > power meter for pep reading. I see 4 controls in the box. I have a > reference Bird but I am missing the instructions on how to calibrate the > Heathkit box. > > Can anyone help a little! > > Denis VE6AQ > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Jim" Message-ID: <002901c15ca3$f5e477e0$c4efbfa8@jims> Wow....That's really interesting! That really is a clone. As someone pointed out, the cooling system is not the same. Doesn't draw cooling air from around the transformer. My guess that it was not built by the Side Band Engineers that we are all familiar. Their logo was always block letters and was blue. Although the logo in the photographs is difficult to make out. My guess is that this was catered toward the "CB" market. In addition, I would say that the SBE referred to in the auction stands for something else. I know that Side Band Engineers did make a small amplifier that had a similar model number. As I remember it had sweep tubes in it. Curious if it has some actual Heathkit parts in it. Thanks for the posting! Quite interesting. 73 Jim W7RY ----- Original Message ----- From: "skipp isaham" To: Sent: Tuesday, October 23, 2001 7:47 PM Subject: [AMPS] A Clone of an SB-220 by SBE > > re: clone of an SB-220 by SBE > - > Hello again, > - > An interesting sale now on Ebay... I ran across > a clone of an SB-220, made by SBE. Don't know if this > model is a production unit, the below URL will give you > a good view. > - > http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=1287426542 > - > item number 1287426542 > - > I have no association with the auction, but I thought > the clone job was pretty neat to look at so I'll mention > it here. SBE was south of San Francisco and no > longer does radio gear. > - > cheers > skipp > ________________________________________________________________ > GET INTERNET ACCESS FROM JUNO! > Juno offers FREE or PREMIUM Internet access for less! > Join Juno today! For your FREE software, visit: > http://dl.www.juno.com/get/web/. > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Jim" There you go! Call a professional if you don't know what to do! That was a GOOD call! 73 and glad the problem is fixed. Jim W7RY ----- Original Message ----- From: "Tom Martin" To: "AMPS REFLECTOR" Sent: Wednesday, October 24, 2001 8:02 AM Subject: [AMPS] Ground loop > > Thanks to all that offered suggestions. The electrician just left and > the problem is solved. There were two reasons for the problem. First, > a 3-way switch was used instead of a 2-way and it was wired > incorrectly. The ground wire was connected to the traveler lug instead > of the green ground lug which wasn't even on the switch. Also, all of > the ground wires on several receptacles and overhead lights on the > circuit were just wrapped around the Romex and not connected. One thing > nice about living in a small town in the U.P. and being a retired > teacher is that former students own electrical companies and respond > quickly. > > 73, Tom > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > w7ry@earthlink.net -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From n4zr@contesting.com Wed Oct 24 17:25:44 2001 From: n4zr@contesting.com (Pete Smith) Date: Wed, 24 Oct 2001 12:25:44 -0400 Subject: [AMPS] A Clone of an SB-220 by SBE In-Reply-To: <002901c15ca3$f5e477e0$c4efbfa8@jims> References: <20011023.194733.-293603.1.nospam4me@juno.com> Message-ID: <3.0.5.32.20011024122544.00a0fce0@pop.abs.adelphia.net> At 08:53 AM 10/24/01 -0700, Jim wrote: > >Wow....That's really interesting! That really is a clone. As someone >pointed out, the cooling system is not the same. Doesn't draw cooling air >from around the transformer. > >My guess that it was not built by the Side Band Engineers that we are all >familiar. Their logo was always block letters and was blue. Although the >logo in the photographs is difficult to make out. > > My guess is that this was catered toward the "CB" market. Interesting, all right -- unless my eyes are failing me there is no plate bandswitch, and only the 10/11m coil is in place. Also the cooling does not not appear to extend below the chassis, so this amp could be very hard on filament pins. 73, Pete N4ZR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From carlseye@tampabay.rr.com Wed Oct 24 21:16:17 2001 From: carlseye@tampabay.rr.com (carl seyersdahl) Date: Wed, 24 Oct 2001 16:16:17 -0400 Subject: [AMPS] A Clone of an SB-220 by SBE References: Message-ID: <004d01c15cc8$bf60eee0$2e211c18@tampabay.rr.com> >From the description of that amp it sounds like SBE may well stand for "super bad engineering". carl / kz5ca ----- Original Message ----- From: "Steve Katz" To: ; Sent: Wednesday, October 24, 2001 10:26 AM Subject: RE: [AMPS] A Clone of an SB-220 by SBE > > I don't know, but I'd love to hear if anyone knows about this "SBE." > > The only SBE I remember is (was) SideBand Engineers, in Goleta, CA -- which > is *really* far south of San Francisco, like 300 miles (it's adjacent to > Santa Barbara), and they've been gone for many, many years... > > Maybe there's "another" SBE? > > WB2WIK/6 > > "Each success only buys an admission ticket to a more difficult problem." -- > Henry Kissinger > > > -----Original Message----- > > From: Doug Hall [SMTP:doug@nc.rr.com] > > Sent: Wednesday, October 24, 2001 7:03 AM > > To: amps@contesting.com > > Subject: RE: [AMPS] A Clone of an SB-220 by SBE > > > > > > > > > > > -----Original Message----- > > > From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On > > > Behalf Of skipp isaham > > > Sent: Tuesday, October 23, 2001 10:47 PM > > > To: amps@contesting.com > > > Subject: [AMPS] A Clone of an SB-220 by SBE > > > > > An interesting sale now on Ebay... I ran across > > > a clone of an SB-220, made by SBE. Don't know if this > > > model is a production unit, the below URL will give you > > > a good view. > > > - > > > http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=1287426542 > > > - > > > > > > Looking at the pictures gives me the impression that this amp does not use > > the same split-chassis cooling method found in the SB-220. It might, but > > it's not obvious from the photos. Does anyone know? > > > > Doug, K4DSP > > > > > > -- > > FAQ on WWW: http://www.contesting.com/FAQ/amps > > Submissions: amps@contesting.com > > Administrative requests: amps-REQUEST@contesting.com > > Problems: owner-amps@contesting.com > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From kc5vdj@yahoo.com Wed Oct 24 21:29:13 2001 From: kc5vdj@yahoo.com (Jim Bryant) Date: Wed, 24 Oct 2001 15:29:13 -0500 Subject: [AMPS] A Clone of an SB-220 by SBE References: <20011023.194733.-293603.1.nospam4me@juno.com> <3.0.5.32.20011024122544.00a0fce0@pop.abs.adelphia.net> Message-ID: <3BD72499.9090808@yahoo.com> Pete Smith wrote: > At 08:53 AM 10/24/01 -0700, Jim wrote: > >>Wow....That's really interesting! That really is a clone. As someone >>pointed out, the cooling system is not the same. Doesn't draw cooling air >> >>from around the transformer. > >>My guess that it was not built by the Side Band Engineers that we are all >>familiar. Their logo was always block letters and was blue. Although the >>logo in the photographs is difficult to make out. >> >>My guess is that this was catered toward the "CB" market. >> > > Interesting, all right -- unless my eyes are failing me there is no plate > bandswitch, and only the 10/11m coil is in place. Also the cooling does > not not appear to extend below the chassis, so this amp could be very hard > on filament pins. > > 73, Pete N4ZR Yeah, and look very carefully at the Grid meter... If I'm not mistaken, the needle looks like it's stuck all the way to the right! jim -- ET has one helluva sense of humor! He's always anal-probing right-wing schizos! ----------------------------------------------------- POWER TO THE PEOPLE! ----------------------------------------------------- "Religious fundamentalism is the biggest threat to international security that exists today." United Nations Secretary General B.B.Ghali, 1995 _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From w9op@athenet.net Wed Oct 24 21:31:43 2001 From: w9op@athenet.net (Mark Michel) Date: Wed, 24 Oct 2001 21:31:43 +0100 Subject: [AMPS] LK-8877 Message-ID: <005c01c15cca$e5af3aa0$0100000a@w9op> I recently acquired an Amp Supply LK-8877. Does anyone have a schematic and/or manual? Any information would be appreciated. 73, Mark W9OP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From wc6w@juno.com Wed Oct 24 21:32:26 2001 From: wc6w@juno.com (Radio WC6W) Date: Wed, 24 Oct 2001 13:32:26 -0700 Subject: [AMPS] FS: ICOM 2KL Mod kit Message-ID: <20011024.140216.20470.0.WC6W@juno.com> I have a plastic bag of parts from the estate stuff I've been selling that is marked "2KL Mod Kit" It contains a pair of Takamisawa relays, two air wound coils, two small coils, half a dozen high voltage disc caps, some kind of diode and an another pair of disk caps. No instructions. Asking $25, plus postage, if necessary. Plus shipping, if necessary... Contact: Marv WC6W 310 649 3111 (reasonable hours Pacific Time please) or via return e-mail * ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From wc6w@juno.com Wed Oct 24 21:34:10 2001 From: wc6w@juno.com (Radio WC6W) Date: Wed, 24 Oct 2001 13:34:10 -0700 Subject: [AMPS] FS: Fans Message-ID: <20011024.140216.20470.1.WC6W@juno.com> NOS fan that fits some Japanese radio...marked: 57 10.01 100V The wires from the motor are about 4' long and are terminated in a 2 pin JST connector. The impeller has 8 blades and is 7 cm in diameter. It is mounted to a U shaped metal frame with four mounting holes spaced 5cm by 9cm $10 Listed below are all serious squirrel cage type fans: Redmond Model BL-6 115 VAC .8A 60Hz 3000 RPM 4" round intake, 2.5" square output flange, weighs 6lbs. used -- $20 ILG Electric Ventilation 17-18-022A encased motor with 181-009-EA fan 115/230 VAC 1.6A/.8A 50/60Hz 3000 RPM 4�" round intake, 3�" x 4-3/4" rectangular output flange, weighs 25lbs. used -- $30 Kooltronic Model DF1F016N Dual fan style 230 VAC 1.2A 60Hz 3000 RPM 3�" round intakes, 2.5" x 5" rectangular output flanges, 16" long by about 7" diameter overall, weigh 15lbs. These look like NOS but, they are a mite dusty from storage -- $40 ea (3 available) Plus shipping, if necessary... Contact: Marv WC6W 310 649 3111 (reasonable hours Pacific Time please) or via return e-mail * ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From wc6w@juno.com Wed Oct 24 21:36:50 2001 From: wc6w@juno.com (Radio WC6W) Date: Wed, 24 Oct 2001 13:36:50 -0700 Subject: [AMPS] FS: Vacuum Caps & Other Vacuum things Message-ID: <20011024.140216.20470.4.WC6W@juno.com> ****** VACUUM CAPACITORS & other Vacuum things *********** Jennings Vacuum Variables -- all used (or at least aged) UCS-300-15S 300pF 15KV $200 with standard puller, later manufacture (blue) UCSL-750 750pF 3KV $125 with standard puller UCSL-1000 1000pF 3KV $125 with standard puller R1G SPST 20KV 20Amp Vacuum Switch $80 ---Fixed vacuum caps-- Jennings VC-12 12pF 20KV $20 Jennings 50pF 86KV $86 Western Elec 100pF 5KV $30 (This one hi-pot checked @ 14KV) --- Vacuum Relays -- Old "T" style vacuum relays, the coil slips over one leg of the glass enclosed contact assembly -- One of the contacts has a Penta Labs part number: 420 53 3875. The coils are 28V. $10 ea Struthers Dunn Type 78CCA109 "Keying Relay" which consists of a vacuum relay mounted on top of a small (2"x3"x4") metal enclosure. There is a 15 pin Jones connector on the side of the box. I believe that there are some auxiliary contacts in the box in addition to the vacuum relay. 28VDC. $15 Plus shipping, if necessary... Contact: Marv WC6W 310 649 3111 (reasonable hours Pacific Time please) or via return e-mail * ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From wc6w@juno.com Wed Oct 24 21:35:57 2001 From: wc6w@juno.com (Radio WC6W) Date: Wed, 24 Oct 2001 13:35:57 -0700 Subject: [AMPS] FS: Capacitors Message-ID: <20011024.140216.20470.3.WC6W@juno.com> *********** Air Variable Capacitors ******** Johnson T9-5 minature vertical PC mount trimmers 1.9-15.7 pF, Silver Plated machined plates -- NOS 2/$1 G.I. Corp 70 pF, .080" air spacing, about 3.5"x3.5"x3" overall, �" shaft $2ea (2 available) National Type DX 500pF variable capacitors, approx. 3" X 3" x 3" overall fairly good condition. $10 ea. Remler "scissors" variables. Type 630 350pF $25 Type 631 500pF $25 Hammarlund NZ-10 Neutralizing capacitors, shiny NOS, $20 pair ...and a whole bunch of used Neutralizing capacitors as listed below $5 ea Bud NC-853 (2 available) NC-1000 (2 available) Hammurlund N-10 (ceramic repaired) National NC-800 (old version - ceramic repaired) NC-800 (later version) NC-150 Johnson 150-375 Millen (part no. unknown) w/ 2-5/32" disks (part no. unknown) piston style Unknown Mfgr w/ 2" disks **** Ceramic Doorknob & Disk caps *** These are used Centralab or similar -- $5 ea or 5/$20 500pF 10KV "TV" style 68pF 5KV 850 series ------- These are NOS disks by KD & Erie $3ea or 4/$10 1500pF 7.5KV .01uF 4KV ------ And a couple NOS Silver Mica caps. 2200 pF 500V CM06 $1 ea 5100 pF 500V CM07 (high current rating) $2 ea Plus shipping, if necessary... Contact: Marv WC6W 310 649 3111 (reasonable hours Pacific Time please) or via return e-mail * ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From wc6w@juno.com Wed Oct 24 21:35:28 2001 From: wc6w@juno.com (Radio WC6W) Date: Wed, 24 Oct 2001 13:35:28 -0700 Subject: [AMPS] FS: Roller Coils & B&W coil stock Message-ID: <20011024.140216.20470.2.WC6W@juno.com> ***** Roller Coils ****** B&W 3853 72 uH NOS but, a mite tarnished from age. $60 Johnson 229-202 18uH used good, $50 La Pointe L-0201 406-1 (identical to a Johnson 229-201) 10 uH. used good, $30 ***** B&W Air Dux coils ***** These are all shiny NOS, 10" lengths, unless noted otherwise #2408T 3" dia, 8TPI, #14 wire -- $30 #2008-31 2.5"dia x 4" long , 8TPI, #14 wire with 2 turn #14 link at center. NIB $25 #1604T 2" dia, 4TPI, #12 wire, slight tarnish $20 #1208T 1.5" dia, 6TPI, #12 wire, slight tarnish $20 #1216T 1.5" dia, 16TPI, #16 wire, somewhat tarnished $20 #1006T 1.25" dia, 6TPI, #14 wire, somewhat tarnished $15 These are all somewhat tarnished NOS partial lengths #1008T 1.25" dia, 8 TPI, #16 wire, 8" long -- $12 #1016T 1.25" dia, 16 TPI, #20 wire, 8" long -- $12 #1032T 1.25" dia, 32 TPI, #24 wire, 5" long -- $10 and a couple of Illumintronic Engineering parts 375 7367-P1 -- 1.5" dia.x 5.75" winding w/ indented turns, 14 TPI, #17, 7" overall including plastic center support, un-used somewhat tarnished $25 980-0121-000 -- 2.5" dia. x 7.5" winding w/ indented turns, 8 TPI, #14, 9.5" overall including plastic center support, used somewhat tarnished but, no turns soldered $30 Plus shipping, if necessary... Contact: Marv WC6W 310 649 3111 (reasonable hours Pacific Time please) or via return e-mail * ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From wc6w@juno.com Wed Oct 24 21:38:38 2001 From: wc6w@juno.com (Radio WC6W) Date: Wed, 24 Oct 2001 13:38:38 -0700 Subject: [AMPS] FS: Coax relay & Coax connectors Message-ID: <20011024.140216.20470.6.WC6W@juno.com> ***** Used Coax Connectors **** These are mostly used, fairly clean, (at least 80%) Amphenol parts. There are anywhere from about 4 to 25 of each type available. UHF female - UHF female barrel connectors -- $1 ea UHF male - BNC female adapters -- $2 ea UHF female - BNC male adapters -- $2 ea UHF F-M-F Tees -- $2 ea Andrews Heliax UHF connectors 1/2" 44AP male -- $10 (last one) UG-57B/U N Male-Male connector -- $4 ea UG-635/U C Female - BNC Male adapter -- $5 ea UG-636A/U BNC Female - C Male adapter -- $5 ea UG-259A/U 91836 -- HN female to LC female bulkhead adapter -- $30 SMA Female-Female Bulkhead connector -- $1 ea ***** New Coax Connectors ***** UG-1213/U HN Male Cable connector NOS -- $10 Kings KH-39-11 HN Female Cable connector NOS -- $10 Below are all new crimp on connectors, with all hardware, in individual plastic bags; early-mid 1990's date codes. I believe that they are all for RG-59 size cable. Kings Electronics KC-59-642-M06 BNC Cable Male -- $1 ea KA-59-385-M06 TNC Cable Male -- $1 ea KA-19-43 TNC Bulkhead Female -- $1 ea *** Coax Antenna Relay **** Dow-Key DK-60 style 110 VAC coil -- $30 (last one) (3) UHF connectors. Somewhat old looking on the outside but, I popped the inspection port and all the contacts are all happy -- goes "clunk" upon application of the appropriate voltage. Plus shipping, if necessary... Contact: Marv WC6W 310 649 3111 (reasonable hours Pacific Time please) or via return e-mail * ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From wc6w@juno.com Wed Oct 24 21:37:52 2001 From: wc6w@juno.com (Radio WC6W) Date: Wed, 24 Oct 2001 13:37:52 -0700 Subject: [AMPS] FS: RF Ammeters, Time Meters & Panel Meters Message-ID: <20011024.140216.20470.5.WC6W@juno.com> ******* Panel Meters ******** Analog Devices AD2004 4� Digit LED 2 (1.9999) volt Panel Meter; NOS w/ data sheet $40 Datel DM-3100L-7089 3� Digit LED Panel meter; range & condition unknown. $10 FLW Model 204B2, ER2 & model 204B-2D1,ER2,01 digital panel meters w/internal 120VAC power supply. 4 digit display plus a minus sign; 3� or full 4 digits ?? Full scale unknown-- $25 pair GE 50-283013MTMT1 3" thin edgewise panel meter 10V scale NOS in old box -- $15 GE DW-44 2" round 8A RF Ammeters w/ internal thermocouple $15 ea GE 50-240001AAAA1 2" round 100000 Hour Running Time meters 120VAC 60Hz NOS $20 ea A.W. Haydon miniature 10000 Hour running time meter. Case is about 1/2" square (exclsive of mounting flange) by 1" deep. 115VAC 400Hz NOS $15 Hobbs 120 VAC 60Hz 100000.00 (Yes, displays down to 100th's!) Hour running time meter about 1" high by 2" wide rectangular with triangular shaped mounting ears. NOS $20 ea Motorola 52B892096 3�" Square Meter (movement actually made by Simpson). This is some kind of tuning (or deviation?) meter with a 12 pin connector (like a 9 pin miniature tube outline plus 3 extra pins in the center) wired to the meter. $15 Simpson Model 45 3" round VU meter $20 Simpson 3" sq modern plastic 500-0-500ua movement w/ 50-0-50 scale -- $10 Triplett 320-G 3�" rectangular. 50-0-50 ua -- $15 Triplett 321T 1 Amp 3.5" Round meter NIB -- $20 Triplett 327T 10 Volt 3" Square meter NIB -- $20 Westinghouse 3�" Square RX-35 series meters, used -- $10 each 15 VDC 20 VAC 35KV (2mA full scale on this last unit) Westinghouse 2" round 9A RF Ammeters w/ internal thermocouple $15 ea Weston 301 3" square 3A RF Ammeter (requires external thermocouple that I don't have) $7 Plus shipping, if necessary... Contact: Marv WC6W 310 649 3111 (reasonable hours Pacific Time please) or via return e-mail * ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Jim" <3.0.5.32.20011024122544.00a0fce0@pop.abs.adelphia.net> <3BD72499.9090808@yahoo.com> Message-ID: <002c01c15ccf$4d70ac60$15e085ce@jims> Yes....Your eyes are failing. There is another coil under the 10/15 meter coil. There is also an 5 position bandswitch on the front panel. My guess is that the meter indication that you are seeing is the plate voltage. When 3-500 tubes short, there is NEGITIVE grid current. 73 Jim W7RY P.S. Is this site designed to pass along your political statements ? ----- Original Message ----- From: "Jim Bryant" To: "Pete Smith" Cc: Sent: Wednesday, October 24, 2001 1:29 PM Subject: Re: [AMPS] A Clone of an SB-220 by SBE > > Pete Smith wrote: > > > At 08:53 AM 10/24/01 -0700, Jim wrote: > > > >>Wow....That's really interesting! That really is a clone. As someone > >>pointed out, the cooling system is not the same. Doesn't draw cooling air > >> > >>from around the transformer. > > > >>My guess that it was not built by the Side Band Engineers that we are all > >>familiar. Their logo was always block letters and was blue. Although the > >>logo in the photographs is difficult to make out. > >> > >>My guess is that this was catered toward the "CB" market. > >> > > > > Interesting, all right -- unless my eyes are failing me there is no plate > > bandswitch, and only the 10/11m coil is in place. Also the cooling does > > not not appear to extend below the chassis, so this amp could be very hard > > on filament pins. > > > > 73, Pete N4ZR > > > Yeah, and look very carefully at the Grid meter... If I'm not mistaken, the needle looks like it's stuck all the way to the right! > > > jim > -- > ET has one helluva sense of humor! > He's always anal-probing right-wing schizos! > ----------------------------------------------------- > POWER TO THE PEOPLE! > ----------------------------------------------------- > "Religious fundamentalism is the biggest threat to > international security that exists today." > United Nations Secretary General B.B.Ghali, 1995 > > > _________________________________________________________ > Do You Yahoo!? > Get your free @yahoo.com address at http://mail.yahoo.com > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From kc5vdj@yahoo.com Wed Oct 24 22:05:10 2001 From: kc5vdj@yahoo.com (Jim Bryant) Date: Wed, 24 Oct 2001 16:05:10 -0500 Subject: [AMPS] Amps and Microprocessors Message-ID: <3BD72D06.6080107@yahoo.com> What experiences have people on this list had with both shielding microprocessor control circuitry and display electronics internal to a power amplifier from the intense RF fields as well as preventing the microprocessor and display circuitry from inducing a hash onto the output signal? My thoughts involve a brass box, vented, with forced air cooling, that would be chassis grounded, and with common-mode chokes on all leads coming from this box. Would this be enough? Also, any suggestions on which ADC/Multimeter chips that have a fast enough response time as well as reasonable RF immunity? This is for a wet-dream amp project using a 4CX1600B that I've been acquiring parts for for about a year or so, and am about halfway to getting to the starting point. My goal is to get as near hands-free as possible, with realtime monitoring of every aspect of circuit operation on a LCD panel [no multimeter switches], automatic tune-up, ALC, hands-free realtime screen grid protection that would require no operator intervention and not result in the amplifier being shutdown or bypassed [IMHO, idiot lights are a dumb idea, and can go unnoticed long enough for damage to occur; coming from an enterprise computing background, downtime is unacceptable, so, plate-voltage cutoff when an excessive screen-current condition exists is IMHO just as bad as an idiot light. Amplifier shutdown should only happen when signs of catastrophic failure are detected, rather than a condition that can be corrected in realtime]. Keep in mind that I'm not knocking traditional-design manually-operated amplifiers, in the hands of a good attentive operator, they do just fine. I just want to do my amplifier right. Gawd knows, I'm spending enough money on the traditional parts, I've got no problem with going the extra mile to get the rest of it right. I may do an article on this once it's built, after all, share and enjoy. jim -- ET has one helluva sense of humor! He's always anal-probing right-wing schizos! ----------------------------------------------------- POWER TO THE PEOPLE! ----------------------------------------------------- "Religious fundamentalism is the biggest threat to international security that exists today." United Nations Secretary General B.B.Ghali, 1995 _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From N7CXI@SiliconPixels.com Wed Oct 24 22:47:05 2001 From: N7CXI@SiliconPixels.com (Jim Barber) Date: Wed, 24 Oct 2001 14:47:05 -0700 Subject: [AMPS] LDG DWM-4 and high power? Message-ID: <5.0.2.1.1.20011024144312.020b8b20@mail.elltel.net> Hi folks, Does anyone have any good or bad stories to tell about using an LDG Electronics DWM-4 wattmeter at high power? They recently added a 2KW coupler to their product line, but I'm a little nervous about overshoot. I'm wondering if it could take 2500W or so for a few seconds -when- I screw up? (it's inevitable) Thanks, Jim, N7CXI -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From uncrichie@home.com Wed Oct 24 23:01:57 2001 From: uncrichie@home.com (kurt) Date: Wed, 24 Oct 2001 18:01:57 -0400 Subject: [AMPS] Russian Tube Designation Numbers Message-ID: <001001c15cd7$807a3060$33600941@wall1.pa.home.com> This is a multi-part message in MIME format. ------=_NextPart_000_000D_01C15CB5.F903DB20 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hello all, I'm trying to find out if Russian tube # 6P45C is the same = tube as the 6KG6 and EL-509. If anyone knows for sure or could direct me = to the proper location, it would be greatly appreciated. Also looking = for 6KG6 russian tubes costing less than $16.50 ea, if anyone knows. = Thanks in advance, Kurt, K3KL..... ------=_NextPart_000_000D_01C15CB5.F903DB20 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hello all, I'm trying to find out if = Russian tube #=20 6P45C is the same tube as the 6KG6 and EL-509. If anyone knows for sure = or could=20 direct me to the proper location, it would be greatly appreciated. Also = looking=20 for 6KG6 russian tubes costing less than $16.50 ea, if anyone knows. = Thanks in=20 advance, Kurt,   K3KL.....
------=_NextPart_000_000D_01C15CB5.F903DB20-- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From mdurham@AetherSystems.com Thu Oct 25 00:19:05 2001 From: mdurham@AetherSystems.com (Marty Durham) Date: Wed, 24 Oct 2001 19:19:05 -0400 Subject: [AMPS] In search of BTI LK-1000 manual...second request... Message-ID: <6D1150F4C5ECD41194EB006008F5C618FE6A2C@MMA-MAIL> I sent a request to the reflector about 2 months ago and received many responses (Thanks)... Unfortunately the person who indicated he was going to mail the manual to me hasn't been able to. Is there anyone out there that could help me out? Soft/scanned copy would be fine too... Thanks again in advance... Marty, W1MD mdurham@aethersystems.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From kc5vdj@yahoo.com Thu Oct 25 00:26:39 2001 From: kc5vdj@yahoo.com (Jim Bryant) Date: Wed, 24 Oct 2001 18:26:39 -0500 Subject: [AMPS] Amps and Microprocessors References: <5.0.2.1.1.20011024140922.02116da0@mail.elltel.net> Message-ID: <3BD74E2F.2000906@yahoo.com> Jim Barber wrote: > Jim, > > >>What experiences have people on this list had with both shielding microprocessor control circuitry and display electronics internal to a power amplifier from the intense RF fields as well as preventing the microprocessor and display circuitry from inducing a hash onto the output signal? >> >>My thoughts involve a brass box, vented, with forced air cooling, that would be chassis grounded, and with common-mode chokes on all leads coming from this box. Would this be enough? >> > > Probably, as long as a lot of common-mode RF doesn't exist on the > cabinet in general. It would work as well as the Alphas, which is > pretty well. > > >>Also, any suggestions on which ADC/Multimeter chips that have a fast enough response time as well as reasonable RF immunity? >> > > Something you may want to check into is the BasicX BX-24. It has > 10-bit ADC's, parallel IO, and a onboard multitasking OS. It's > programmed in interpreted BASIC, but at 65000 lines/second, > (not including ADC sampling holds) it's probably plenty fast > enough for an amp controller. One note, tho.. The ADC's are > ground-referenced only, so you'd probably have to use an op-amp > to isolate the plate shunt from the ADC. Anyway: > http://www.basicx.com Sounds pretty good, although your choice of the 8877 is a good one also, I'm a bit leery on using it. I've been toying with the idea of breaking the tasks between seperate processors, and using serial chip-to-chip networking. I've been looking at some of the NEC 32-bit controllers myself, primarily due to their low cost, fast speed, large I/O capability, built-in multi-axis controllers, built-in data conversion, chip-to-chip networking, and wide acceptance for consumer gear. I still haven't made a final choice on the control archetecture, and as I said, I'm open to suggestions. The idea of using the BASIC chips would be helpful to the idea of writing an article on this for others to build, as long as they can program it easily. The main drawback of the NEC chips is that they are flat-pack chips with high pin-counts, and thus hard to work with as far as the mechanics of the soldering, although, it wouldn't be unheard of to simply have a short-run of such boards made and direct the reader to a source for the pre-assembled boards. I have toyed with the idea of using the American-made[?] 8877 over the 4CX1600B, but the idea was to keep the costs down, and the tetrode requires far less consideration on the input circuit, as well as carries a smaller per-tube price tag. Long-term quality and availability is also a factor. Since I don't know what the stock conditions are on the 1600B, the 8877 could be an option if political moves cut off the supply of 1600B's, but since it's hard to measure the possibility of a new cold war with Russia under current conditions, I'm continuing with the choice of the 1600B until it appears they may no longer be available to Americans in the future. Tube availability 5, 10, 20, even 30 and 40 years from now is a factor in this design, and as such, the 8877 COULD end up being a good choice for me too, regardless of the quality/price issue. At present, the Russian tube seems the best choice because of their committment to produce good quality, low-priced power tubes indefinitely, which is something that I just don't see in American companies. Remember, I'm thinking ahead here by multiple decades. My goal is an amplifier that should last in excess of 40 years, with little more than the need for new tubes and maybe one or two filter-cap changouts in-between, with newly manufactured tubes still being available that far in the future. Even if I'm wrong about the duration of power-tube production in the United States, I'm probably correct on the long-term quality and pricing trends on American tubes. If this was the 1960's or 1970's, the choice would be clear: Buy American! Since the 1980's, American quality has gone way down, while the prices have gone way up. The initial arguments in the electronics industry ["unions are destroying us!"] might have been believable in 1980 and '81, but today those arguments hold no weight with the advent of deunionizing such shops ever since the early 80's, and the price/quality trend has multiplied by magnitudes of order in the bad direction, with no end in sight when it comes to declining American quality, and ever-increasing prices. Am I being cynical, or am I just being realistic? I tend to think the latter. The 8877 is a good tube, but it's overpriced, and it's future availability and quality is questionable, although current events could end up dictating it's use in my amplifier. As a collector of old radios, and such, I don't want to have to end up having to get a new tube for this amplifier thirty years from now in the fashion I have to do for some of my radios, for a large number of tubes, it's like trading on the gold or even platinum markets, totally unpredictable, and based on "collector value" rather than on real value [Supply/Demand]. IMHO, domestic business decisions since the 1980's in the electronics industry are the best argument for using Russian tubes. The Russians have a committment to build the best, while keeping prices reasonable. American companies just don't, they do the exact opposite! Even if I end up going commercial with such an amplifier, I'll probably be using foreign parts, because I can't trust the quality of American parts, and have no guarantees as to long-term availablity, high quality, and reasonable pricing. Sad, huh? This is not intended to be a political diatribe. It is intended to be a realistic description of a decision-making process in the initial design of a high-end amplifier, with potential commercial value, intended to have a usable life in excess of 40-50 years. My roomate has a sweep-tube amp using 8950's, he calls it his $150 paperweight, and that he would have to pay someone to take off his hands. The sad thing is that he's right. He tried selling it to me, I said "No freaking way"!. Swan made some bad choices, and they weren't the only one. Business, geopolitical, and technology trends DO have to be considered at the initial design stage of a high-end amplifier. A high-end, modern legal-limit amplifier isn't supposed to be designed as throwaway consumer trash, it's a long-term committment. Trends can change, but the design must be made with forseeable events that can effect the basic design itself. American companies could go back to the values of my grandfather, and provide quality products at reasonable prices again, and even pay their people a good wage. A Cold War could happen over missiles [very easily], and effect the availability of the Russian tubes, but until that happens, and it may not, the Russian tubes seem to be the best decision in the long-term. This of course, is my opinion, and even though it is based on an objective analysis, other people are free to differ, and there are still good American tubes, even though their future availability, quality, and pricing is highly questionable. The real test is of course, to make the decision based on the best available current information, and then wait 40 years. My decision on using the Russian tubes is based on an American business trend that is better than 20 years old now, with no end in sight. It's no mistake that Japan leads the radio industry today, they have a committment to quality as well, and they have a dedicated workforce due to the fact that they are paid a decent wage for their work, and thus take pride in their work. Icom, Yaesu, and Kenwood don't have as high a profit margin as American companies, but they make up for it due to the sheer volume that gets sold because of their high-quality. We can do that here in America again too, but I'm cynical on if it will ever happen. One way to start is to maybe produce the best amplifier on the market, using well-paid American labor, and work from that success, and that's my goal. I have no problem with writing an article on how to build the amplifier, because I know that only a handful of people will ever do so because the average ham these days is an appliance operator that only memorized A, B, C, and D and has no idea what the questions he memorized the answers to on the test were about. Sad, but true. Anyhow, this is starting to sound like a rant, and I want to steer clear of such here. Like I said, I'm not knocking your choice of tube, and I wish you the best. Thank you for the advice on the BASIC chips, I had no idea that they had gotten that fast and capable since their introduction, and I'll consider their use for this task, as it could be a good idea for keeping the control circuitry as simple as possible for the home builder. Like I said, this is a wet-dream amplifier. I thought about building a traditional [1930's-1950's technology] amplifier, but I think going the extra mile is going to make a nicer one. I'm in my 30's, but I'm a next-generation ham. It's high time that power-amplifiers caught up with the second half of the 20th century! jim -- ET has one helluva sense of humor! He's always anal-probing right-wing schizos! ----------------------------------------------------- POWER TO THE PEOPLE! ----------------------------------------------------- "Religious fundamentalism is the biggest threat to international security that exists today." United Nations Secretary General B.B.Ghali, 1995 _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From n4zr@contesting.com Thu Oct 25 01:00:34 2001 From: n4zr@contesting.com (Pete Smith) Date: Wed, 24 Oct 2001 20:00:34 -0400 Subject: [AMPS] A Clone of an SB-220 by SBE In-Reply-To: <002c01c15ccf$4d70ac60$15e085ce@jims> References: <20011023.194733.-293603.1.nospam4me@juno.com> <3.0.5.32.20011024122544.00a0fce0@pop.abs.adelphia.net> <3BD72499.9090808@yahoo.com> Message-ID: <3.0.5.32.20011024200034.00817100@pop.abs.adelphia.net> At 02:03 PM 10/24/01 -0700, you wrote: > >Yes....Your eyes are failing. > >There is another coil under the 10/15 meter coil. There is also an 5 >position bandswitch on the front panel. > >My guess is that the meter indication that you are seeing is the plate >voltage. When 3-500 tubes short, there is NEGITIVE grid current. I can't see the plate bandswitch wafer. I can see something there under the standoff for the plate line, but no switch. 73, Pete N4ZR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From nospam4me@juno.com Thu Oct 25 04:15:21 2001 From: nospam4me@juno.com (skipp isaham) Date: Wed, 24 Oct 2001 20:15:21 -0700 Subject: Fw: [AMPS] In search of BTI LK-1000 manual...second request... Message-ID: <20011024.202407.-239437.1.nospam4me@juno.com> re: BTI amplifier manual - HI Marty and the group, - My original offer that was number 3 on your list is still good. - I probably have a copy you can have for free, or I could make a copy fast enough. Contact me direct off the list with your US Mail Address and I'll send it out. - In regards to the post about the Manual for the LK amplifier. It would be well worth everyone's while to book mark the boat anchor manual archive web site: http://bama.sbc.edu Lot's of amplifier manual live over there... Also consider sending ken what ever you have to share. - cheers skipp - --------- Forwarded message ---------- From: Marty Durham I sent a request to the reflector about 2 months ago and received many responses (Thanks)... Unfortunately the person who indicated he was going to mail the manual to me hasn't been able to. Is there anyone out there that could help me out? Soft/scanned copy would be fine too... Thanks again in advance... Marty, W1MD mdurham@aethersystems.com ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From nospam4me@juno.com Thu Oct 25 04:24:06 2001 From: nospam4me@juno.com (skipp isaham) Date: Wed, 24 Oct 2001 20:24:06 -0700 Subject: [AMPS] SBE Message-ID: <20011024.202407.-239437.2.nospam4me@juno.com> [snip] :My guess that it was not built by the Side Band Engineers :that we are all familiar. Their logo was always block letters :and was blue. Although the logo in the photographs is :difficult to make out. - I'm told by another ham friend (not a member of amps) that Dick of ex Wawasee Electronics bought SB-220's from heath and refaced them with other brands and modified circuits. I have a few example pictures of said projects just in... quite interesting to look at. Terible on a spectral display... - SBE was in the Southern Part of California and in the South SF Bay Area. Toward the end of their "stint" in radio, all kinds of things were made. I've also seen one of their Drake L4 dual 3-500z amplifier clones. - So the magic question is... was the amp made by SBE or is it another Wawasee clone... or some one else's clone with an SBE label. I would guess to venture it is an original SBE product. I've seen similar projects from them that never made it to large scale production. - :I know that Side Band Engineers did make a small amplifier : that had a similar model number. As I remember it had : sweep tubes in it. : Curious if it has some actual Heathkit parts in it. : Jim W7RY - Would you believe a Swan 1200x clone. They were made in much larger numbers and often pop up on Ebay. - cheers skipp - ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Ian White, G3SEK" References: <3BD72D06.6080107@yahoo.com> Message-ID: Jim Bryant wrote: > >What experiences have people on this list had with both shielding microprocessor >control circuitry and display electronics internal >to a power amplifier from the intense RF fields as well as preventing the >microprocessor and display circuitry from inducing a hash >onto the output signal? > >My thoughts involve a brass box, vented, with forced air cooling, that would be >chassis grounded, and with common-mode chokes on all >leads coming from this box. Would this be enough? > >Also, any suggestions on which ADC/Multimeter chips that have a fast enough >response time as well as reasonable RF immunity? > >This is for a wet-dream amp project using a 4CX1600B that I've been acquiring >parts for for about a year or so, and am about halfway >to getting to the starting point. > I can't reply directly to the questions on microprocessors, but some experience with several hundred Triode Boards and Tetrode Boards may be worth sharing. First of all, if the amplifier is well designed and built, the control circuitry should never be subject to intense RF fields. In a homebrew amplifier you can ensure this by keeping the RF compartment well shielded and bypassed, with the power and control in a separate compartment. Tetrode amplifiers are almost entirely homebrew, by people who seem to take reasonable care with the layout and bypassing. Using single-sided boards with reasonable precautions about bypassing, I haven't had any reports of RFI problems. Triode amplifiers are somehow different, because there are so many bad examples of "open plan" layout. People follow those bad examples in their HB amplifiers and the RF crawls everywhere - as I learned from beta-testing the Triode Boards. The worst was the 50MHz "amp from hell" which had so much stray RF it was lighting the front-panel LEDs! Survival in that sort of environment requires high-level control logic with extensive bypassing and choking. After the beta-testing I also changed to a double-sided board, mostly to simplify the layout but it also gave the opportunity to make most of the top-side into a groundplane. That even worked in the "amp from hell". Most of these precautions will be OTT for most amplifiers, but I never know where my boards are going to be used, so it's better to be sure. Turning that experience around to predicting RFI *from* an on-board microprocessor is rather uncertain. My feeling is that a shielded box with bypassed/choked inputs and outputs will be fine - especially if the main layout does a good job of keeping RF only where it belongs. >My goal is to get as near hands-free as possible, with realtime monitoring of >every aspect of circuit operation on a LCD panel [no >multimeter switches], automatic tune-up, ALC, hands-free realtime screen grid >protection that would require no operator intervention >and not result in the amplifier being shutdown or bypassed [IMHO, idiot lights >are a dumb idea, and can go unnoticed long enough for >damage to occur; coming from an enterprise computing background, downtime is >unacceptable, Everybody agrees with that, in principle... but good luck with making that philosophy work in an amateur radio station! I agree that idiot lights should be restricted to announcing what went wrong, and that the amplifier should already have taken its own action... but your ambitions for zero downtime may be unrealistic. If the amplifier was working OK, but now detects a fault condition, then something has gone wrong - and that fault may not be related to either the amplifier or the transceiver. Considering the whole station, from the mains to the antenna, there is a very limited range of fault conditions that the amplifier is capable of fixing on its own. It is often better to make the amplifier safe (hot standby) and alert the operator to the fact that something has gone wrong. This may be where microprocessor control in the amp can reduce downtime by analysing the fault and displaying useful information. >so, plate-voltage cutoff when an >excessive screen-current condition exists is IMHO just as bad as an idiot light. >Amplifier shutdown should only happen when signs >of catastrophic failure are detected, rather than a condition that can be >corrected in realtime]. The whole trick is to know the difference. After more than 25 years of running tetrode amplifiers, often under extreme conditions, I'm still not sure! Even with a system where excessive screen current cuts the HV, I've still not experienced much downtime. Pushing the RESET button brings the amplifier back to hot standby in literally one second. The major downtime is always in finding out what made it trip. A very useful concept is a hierarchy of faults. Alpha amps distinguish between "soft" faults which put the amp into standby, and "hard" faults which shut it down. I do something very similar on the Triode Board. It seems that you're trying to venture into a third and much trickier level, namely "correctable faults" which the amp should be able to handle without interrupting service. One area where microprocessors can score is to distinguish between faults that appear gradually and faults with a very fast rise-time. For example, if screen current is gradually creeping up, a re-tune followed by possible ALC action may be indicated... and there will probably be time to do that. OTOH, if screen current is shooting up very quickly, that probably means the HV has failed, and you want to shut down the amp instantly - if not sooner. A microprocessor can check rise-times by comparing current and previous measurements (with some difficulties about getting comparable measurements with varying SSB modulation) but this takes additional cycle time and gives a slower reaction to catastrophic faults. To get the very best out of a microprocessor-controlled amplifier, it needs lots of attention to the fine details of programming. And I'd still be inclined to implement the catastrophic-failure protection independently in hardware. While the control software is still under development, it could frequently push the amp into the catastrophe zone so it needs some hardware backup. >Keep in mind that I'm not knocking traditional-design manually-operated >amplifiers, in the hands of a good attentive operator, they >do just fine. I understand that, and am offering these comments in exactly the same spirit. >I just want to do my amplifier right. Gawd knows, I'm spending >enough money on the traditional parts, I've got no >problem with going the extra mile to get the rest of it right. > Sounds good to me! I hope these thoughts and experiences are helpful. >I may do an article on this once it's built, after all, share and enjoy. Yes please! 73 from Ian G3SEK Editor, 'The VHF/UHF DX Book' 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.com/g3sek -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jtml@lanl.gov Thu Oct 25 20:41:56 2001 From: jtml@lanl.gov (John T. M. Lyles) Date: Thu, 25 Oct 2001 13:41:56 -0600 Subject: [AMPS] info on resonant chokes II Message-ID: A couple of comments are warranted from the snippets of QSO that were reprinted earlier: At 11:45 PM -0400 10/24/01, 2@vc.net wrote: >// Regulation is not the reason for using a resonant-choke filter. With >a capacitor filter, the peak current is c. 10x higher on the electric A choke filter alone would also do. Or getting heavier service installed for such problems. For systems which may have the load removed and don't want giant chokes on L input filters, the resonant approach offers voltage regulation better than large swinging chokes. An L input filter (which limits inrush during the rectification cycle) degenerates into a capacitive input filter when the L is too small to reach critical value at light load current. There is a significant rise in voltage when the capacitor charges to peak. This is unregulated.... At 11:45 PM -0400 10/24/01, Jim, VE7RF was quoted as writing: > >To get from 5% ripple down to <1% is a piece o >>cake with a simple cap input filter + a 3 phase diode/plate > >xfmr setup. That's a fact - with 3 phase full wave rectified power supplies, there is very little reason to use a big C or a big L since the ripple voltage is already that low. Unless you have extreme phase unbalance! So the inrush current is also low. 3 phase makes transmitter designers much happier. Suprising that Collins used a 3 phase supply AND a resonant filter. 73 K5PRO John -- -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Thu Oct 25 22:15:15 2001 From: 2@vc.net (2) Date: Thu, 25 Oct 2001 14:15:15 -0700 Subject: [AMPS] info on resonant chokes II Message-ID: <200110252114.f9PLEKZ28106@contesting.com> > > A couple of comments are warranted from the snippets of QSO that >were reprinted earlier: > >At 11:45 PM -0400 10/24/01, 2@vc.net wrote: >>// Regulation is not the reason for using a resonant-choke filter. With >>a capacitor filter, the peak current is c. 10x higher on the electric > >A choke filter alone would also do. ... // For constant current loads, a choke filter would do. For rapidly changing current loads, such as Class AB voice-modulated service, only a resonant-L filter or a C-filter will do the job without producing voltage transients. cheers, John - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Vince Staffo" Does anyone know what the spes are for the wire used with the SB-200 Parasitic Suppressors? Type, diameter, and how many turns required on the 47 ohm Carbon Composition Resistors! I broke one and need to make repairs. Thanks, Vince WB2FYZ -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Fri Oct 26 12:16:22 2001 From: 2@vc.net (2) Date: Fri, 26 Oct 2001 04:16:22 -0700 Subject: [AMPS] SB-200 Parasitic Suppressors Message-ID: <200110261115.f9QBFPZ07534@contesting.com> > >Does anyone know what the spes are for the >wire used with the SB-200 Parasitic Suppressors? >Type, diameter, and how many turns required >on the 47 ohm Carbon Composition Resistors! >I broke one and need to make repairs. > The SB-200 was not unconditionslly VHF-stable with the original VHF suppressors. The most common damage from this problem was arcing the open contacts on the 80m Tune-C padder switch - which switches in the 100pF padder on the 80m band. Oscillation is especially a problem with newer production 572Bs because they exhibit more VHF gain than the tubes originally used. Thus, it might be a good idea to improve the suppressor by decreasing its VHF Q and Rp in order to decrease VHF amplification. This means using more Lsupp and more Rsupp. Using resistance-wire instead of copper-wire also helps to decrease VHF Q. The trade-off is that resistance-wire requires an acid flux and Silver-Tin solder to make satisfactorily connections. - Murphy was right: "Nothing is as easy at looks." > cheers, Vince - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From norsan@bright.net Fri Oct 26 12:29:23 2001 From: norsan@bright.net (Norman Hockler) Date: Fri, 26 Oct 2001 07:29:23 -0400 Subject: [AMPS] NEED AL-800 MANUAL In-Reply-To: <3BD595F5.B76F20E3@chartermi.net> Message-ID: <4.2.0.58.20011026072647.009faa50@mail.bright.net> Hi all, Looking for a manual for the Ameritron AL-600. Yes I know I can download it from their web but the schematics do not download with it. Pay for shipping , etc, Thanks Norm N8NH -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ku7i@hotmail.com Fri Oct 26 17:10:27 2001 From: ku7i@hotmail.com (Lane Zeitler) Date: Fri, 26 Oct 2001 09:10:27 -0700 Subject: [AMPS] FS: Swan MK II w/spare 3-500Z Message-ID: >I am selling my much coveted and beloved Swan Mk II hf amp. It has some >mods: > >1. Tuned input professionally installed. Gear train is slaved to the main >bandswitch so you still only turn one switch when changing bands. The tuned >i/p is located on the underside of the chassis via the gear train. Works >great. Bands covered by this mod are 80-40-20-15-10 but the amp tunes up >great with full power on 17 and 12. Sorry but I never got around to adding >160 to this deck although easy enough to do. > >2. Vacuum o/p relay installed. If I remember right it is a Jennings RJ1A >but it has been a while. The input relay is a generic clanker but the mod >input/output relay mod was done because the original ceramic relay crapped >out and these relays were on hand. Works great. > >3. PS Electrolytics were replaced a few years ago. The Ep on the "ssb" mode >is around 3100 and very gently pegs the 3kv meter, the "cw" mode is around >1800 volts. > >4. The previous owner added soft start that only works if the amp is wired >for 240. The compononents are still there but I bypassed this mod. You will >have to revert it back to how he did it if you want to use this mod (this >soft start must be completely bypassed for 120 vac operation). The >schematic is in the manual. > >5. New(er) 3-500Zs. I do not remember if they are both Eimacs or if one of >them is an Amperex but the deck does full output, or the typical 1300 to >1500 out depending upon the band. I also have a spare full out (used) >3-500Z. Again, I do not remember if it is Eimac or Amperex. This comes with >the amp. > >6. Fan speed mod. Potentiometer added to the rear of the power supply to >control the speed of the ps cooling fan. I always leave it on max. > >7. Cooling fans for the deck and ps were overhauled two years ago. Fans >were taken down to parade rest and the bearings were re-packed. Fans are so >quiet that you can not even hear them when turned on. > >This amp has been working great for the last two years and I hate to sell >it because it works so good but for personal reasons I must sell it > >Price is $700 + UPS ground shipping. Three boxes: rf deck, supply, tubes. I >have no pictures but the condx of the amp is very good to excellent. If you >are not happy I will refund your money. > >Lane Zeitler >Ku7i >San Diego > > _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ad5gb@yahoo.com Sun Oct 28 04:48:28 2001 From: ad5gb@yahoo.com (Randall DuCharme) Date: Sat, 27 Oct 2001 21:48:28 -0700 (PDT) Subject: [AMPS] Henry 1KD5 Rectifier question Message-ID: <20011028044828.44069.qmail@web20908.mail.yahoo.com> Greetings, I have a 1KD-5 that I've been told has been distorting. The symptoms described lead me to thinking there was a PS problem. The amp was given to me a while back with a bad transformer. I just replaced it at the time and used it for awhile without doing any other checking. In searching for the cause of the described distortion, I ran across something that I'm not sure I understand. The amp has 2 large rectifier modules (Semtech SDHD-15K) that measure a little better than 10 meghoms in the forward direction with a DVOM. Having never worked with these devices I'm not too sure, but I'd think that there's something wrong here. Anyone know about these things? Thanks much. __________________________________________________ Do You Yahoo!? Make a great connection at Yahoo! Personals. http://personals.yahoo.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sun Oct 28 08:26:27 2001 From: 2@vc.net (2) Date: Sun, 28 Oct 2001 01:26:27 -0700 Subject: [AMPS] Henry 1KD5 Rectifier question Message-ID: <200110280825.f9S8PRZ08454@contesting.com> > >Greetings, > >I have a 1KD-5 that I've been told has been >distorting. The symptoms described lead me to >thinking there was a PS problem. A single 3-500Z will distort when driven by more than c. 65w at this anode V. A workaround is to add some R in series with the cathode drive coupling capacitor to develop RF-negative feedback. For 100w drive it takes c. 25-ohms. >The amp was given to >me a while back with a bad transformer. I just >replaced it at the time and used it for awhile without >doing any other checking. > >In searching for the cause of the described >distortion, I ran across something that I'm not sure I >understand. The amp has 2 large rectifier modules >(Semtech SDHD-15K) that measure a little better than >10 meghoms in the forward direction with a DVOM. HV rectifier stacks need to be measured in the forward direction with at least 1v per P?/P/N junction. DMMs typically supply c. 1,5v max. In the reverse direction, rectifiers need to be checked for piv with a high-pot. However, if a HVPS is making normal V, the rectifiers have gotta be ok. >Having never worked with these devices I'm not too >sure, but I'd think that there's something wrong here. > Your 3-500Z may be distorting because it is running out of emission due to the use of c. 5.8v on the approx. 4.8v filament. When a 1KD-5 is operated in Japan, where they have 200v mains, the filament v. is ideal. Typical emissive life in the U.S. is c. 200-hours in a stock 1KD-5. Does Henry Radio sell replacement tubes? - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Carsten.Esch@APPELLO.DE Sun Oct 28 11:48:10 2001 From: Carsten.Esch@APPELLO.DE (Carsten Esch) Date: Sun, 28 Oct 2001 12:48:10 +0100 Subject: [AMPS] tube with handle (4CX10000) plus socket for sale Message-ID: <55BE14EA7781FE4DB264F0B50478EEAB0669C8@appd02.appello1.de> Hi there, my 3CX3000A7 amp is still running fine and my time for building amplifier is limited to the time being so I decided to sell my EIMAC 4CX10000 tube (NEW!), complete with socket. If interested I would be glad to hear your offer. 73sss Carsten, DL6LAU -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ad5gb@yahoo.com Sun Oct 28 13:55:58 2001 From: ad5gb@yahoo.com (Randall DuCharme) Date: Sun, 28 Oct 2001 05:55:58 -0800 (PST) Subject: [AMPS] Henry 1KD5 Rectifier question In-Reply-To: <200110280825.f9S8PRZ08454@contesting.com> Message-ID: <20011028135558.93358.qmail@web20901.mail.yahoo.com> --- 2 <2@vc.net> wrote: > >I have a 1KD-5 that I've been told has been > >distorting. The symptoms described lead me to > >thinking there was a PS problem. > > A single 3-500Z will distort when driven by more > than c. 65w at this > anode V. A workaround is to add some R in series > with the cathode drive > coupling capacitor to develop RF-negative feedback. > For 100w drive it > takes c. 25-ohms. I didn't think that I was driving it even that hard... but will double check.... and be sure to keep it below the 65W level. It seems to me that if I get too much higher than that, Ig gets too high anyway. > >In searching for the cause of the described > >distortion, I ran across something that I'm not > sure I > >understand. The amp has 2 large rectifier modules > >(Semtech SDHD-15K) that measure a little better > than > >10 meghoms in the forward direction with a DVOM. > > HV rectifier stacks need to be measured in the > forward direction with at > least 1v per P?/P/N junction. DMMs typically supply > c. 1,5v max. In the > reverse direction, rectifiers need to be checked for > piv with a high-pot. > However, if a HVPS is making normal V, the > rectifiers have gotta be ok. I didn't realize that these were diode stacks. I guess I thought of them as a single ( or in this case double ) diode device. TNX > Your 3-500Z may be distorting because it is running > out of emission due > to the use of c. 5.8v on the approx. 4.8v filament. > When a 1KD-5 is > operated in Japan, where they have 200v mains, the > filament v. is ideal. Interesting. This possibility I never considered, since I was able to get good output ( 600 watts or so ) with reasonable drive. Since I don't know what the orignal transformer supplied, I can't say first hand what the conditions were before I got the amp. > Typical emissive life in the U.S. is c. 200-hours in > a stock 1KD-5. Does > Henry Radio sell replacement tubes? I don't know. The should maybe furnish them gratis if they designed the amp so that it operates outside of the tube manufacturer's specs. :-) Actually, I hope to have my 4x813 project amp running soon and won't need to bother with this any further. Are you available for on-air testing? :-) Thanks much for your time and thoughts __________________________________________________ Do You Yahoo!? Make a great connection at Yahoo! Personals. http://personals.yahoo.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sun Oct 28 16:35:53 2001 From: 2@vc.net (2) Date: Sun, 28 Oct 2001 08:35:53 -0800 Subject: [AMPS] tube with handle (4CX10000) plus socket for sale Message-ID: <200110281634.f9SGYoZ22357@contesting.com> > >Hi there, > >my 3CX3000A7 amp is still running fine and my time for building amplifier is >limited to the time being so I decided to sell my EIMAC 4CX10000 tube >(NEW!), complete with socket. If interested I would be glad to hear your >offer. > Thanks for the opportunity, Carsten, but I am too ancient to build another Plywood Box amplifier. Someone on AMPS should be interested. I have a suitable blower that I will send to the buyer of the 4cx10k+socket for the cost of shipping. cheers - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sun Oct 28 16:35:55 2001 From: 2@vc.net (2) Date: Sun, 28 Oct 2001 08:35:55 -0800 Subject: [AMPS] Henry 1KD5 Rectifier question Message-ID: <200110281634.f9SGYqZ22365@contesting.com> > > >--- 2 <2@vc.net> wrote: > >> >I have a 1KD-5 that I've been told has been >> >distorting. The symptoms described lead me to >> >thinking there was a PS problem. >> >> A single 3-500Z will distort when driven by more >> than c. 65w at this >> anode V. A workaround is to add some R in series >> with the cathode drive >> coupling capacitor to develop RF-negative feedback. >> For 100w drive it >> takes c. 25-ohms. > >I didn't think that I was driving it even that hard... >but will double check.... and be sure to keep it below >the 65W level. It seems to me that if I get too much >higher than that, Ig gets too high anyway. > The 3-500Z is difficult to damage from excessive grid current because it has a grid that can be run at red-heat for brief periods without a problem. My guess is that the grid contains molybdenum. Tune for max RF out with c. 65w drive and grid-current will be good. >>... ... >I didn't realize that these were diode stacks. I >guess I thought of them as a single ( or in this case >double ) diode device. TNX > ur welcome. >> Your 3-500Z may be distorting because it is running >> out of emission due >> to the use of c. 5.8v on the approx. 4.8v filament. >> When a 1KD-5 is >> operated in Japan, where they have 200v mains, the >> filament v. is ideal. > >Interesting. This possibility I never considered, >since I was able to get good output ( 600 watts or so >) with reasonable drive. Since I don't know what the >orignal transformer supplied, I can't say first hand >what the conditions were before I got the amp. > With a stock amp., it is helpful to have a free supply of new tubes. >> Typical emissive life in the U.S. is c. 200-hours in >> a stock 1KD-5. Does >> Henry Radio sell replacement tubes? > >I don't know. The should maybe furnish them gratis if >they designed the amp so that it operates outside of >the tube manufacturer's specs. :-) > Very funny. >Actually, I hope to have my 4x813 project amp running >soon and won't need to bother with this any further. >Are you available for on-air testing? :-) > Yes >Thanks much for your time and thoughts > ur welcome, Randy cheers - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ad5gb@yahoo.com Sun Oct 28 17:21:32 2001 From: ad5gb@yahoo.com (Randall DuCharme) Date: Sun, 28 Oct 2001 09:21:32 -0800 (PST) Subject: [AMPS] Henry 1KD5 Rectifier question Message-ID: <20011028172132.48587.qmail@web20907.mail.yahoo.com> --- 2 <2@vc.net> wrote: > The 3-500Z is difficult to damage from excessive > grid current because it > has a grid that can be run at red-heat for brief > periods without a > problem. My guess is that the grid contains > molybdenum. Tune for max > RF out with c. 65w drive and grid-current will be > good. At ~65 watts drive I get 130ma grid, 450ma plate and ~700 watts out. Power levels are an estimate. My tuner meter was adjusted to match a Bird meter as closely as possible, (some time ago). The accuracy varies depending on where in the tuner meter's scale it's running. Anyway, I tend to stay at or under Henry's recommended 400ma Ip and 130ma Ig. > >> Your 3-500Z may be distorting because it is > running > >> out of emission due > >> to the use of c. 5.8v on the approx. 4.8v > filament. > >> When a 1KD-5 is > >> operated in Japan, where they have 200v mains, > the > >> filament v. is ideal. > > > >Interesting. This possibility I never considered, > >since I was able to get good output ( 600 watts or > so > >) with reasonable drive. Since I don't know what > the > >orignal transformer supplied, I can't say first > hand > >what the conditions were before I got the amp. > > > With a stock amp., it is helpful to have a free > supply of new tubes. Well.... I measured the fil. volts. You were right... 5.85V at the tube pins. And this is with THEIR replacement XFMR for this unit. __________________________________________________ Do You Yahoo!? Make a great connection at Yahoo! Personals. http://personals.yahoo.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Sun Oct 28 18:58:37 2001 From: 2@vc.net (2) Date: Sun, 28 Oct 2001 10:58:37 -0800 Subject: [AMPS] Henry 1KD5 Rectifier question Message-ID: <200110281857.f9SIvYZ24796@contesting.com> > > >--- 2 <2@vc.net> wrote: > >> The 3-500Z is difficult to damage from excessive >> grid current because it >> has a grid that can be run at red-heat for brief >> periods without a >> problem. My guess is that the grid contains >> molybdenum. Tune for max >> RF out with c. 65w drive and grid-current will be >> good. > >At ~65 watts drive I get 130ma grid, 450ma plate 450mA is in the non-linear region of the constant-current curves. >and~700 watts out. Power levels are an estimate. My >tuner meter was adjusted to match a Bird meter as >closely as possible, (some time ago). The accuracy >varies depending on where in the tuner meter's scale >it's running. Anyway, I tend to stay at or under >Henry's recommended 400ma Ip and 130ma Ig. > >> >> Your 3-500Z may be distorting because it is >> running >> >> out of emission due >> >> to the use of c. 5.8v on the approx. 4.8v >> filament. >> >> When a 1KD-5 is >> >> operated in Japan, where they have 200v mains, >> the >> >> filament v. is ideal. >> > >> >Interesting. This possibility I never considered, >> >since I was able to get good output ( 600 watts or >> so >> >) with reasonable drive. Since I don't know what >> the >> >orignal transformer supplied, I can't say first >> hand >> >what the conditions were before I got the amp. >> > >> With a stock amp., it is helpful to have a free >> supply of new tubes. > >Well.... I measured the fil. volts. You were right... >5.85V at the tube pins. And this is with THEIR >replacement XFMR for this unit. > I dropped a 1KD-5's stock fil. potential by 1.0v to 4.8v. I accomplished this by using smaller gauge wire in the filament ckt. Teflon insulation is best. cheers - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ad5gb@yahoo.com Sun Oct 28 22:53:59 2001 From: ad5gb@yahoo.com (Randall DuCharme) Date: Sun, 28 Oct 2001 14:53:59 -0800 (PST) Subject: [AMPS] Henry 1KD5 Rectifier question In-Reply-To: <200110281857.f9SIvYZ24796@contesting.com> Message-ID: <20011028225359.55786.qmail@web20903.mail.yahoo.com> Greetings, --- 2 <2@vc.net> wrote: > >--- 2 <2@vc.net> wrote: > > > >> The 3-500Z is difficult to damage from excessive > >> grid current because it > > > >At ~65 watts drive I get 130ma grid, 450ma plate > > 450mA is in the non-linear region of the > constant-current curves. 3-500Z curves are one set of curves that I do not have. I never really intended to do much with this tube. Can you, or anyone else for that matter, point me to any web resources furnishing the curves? I have found a couple of datasheets in my search, but no constant-current curves. > >Well.... I measured the fil. volts. You were > right... > >5.85V at the tube pins. And this is with THEIR > >replacement XFMR for this unit. > > > I dropped a 1KD-5's stock fil. potential by 1.0v to > 4.8v. I accomplished > this by using smaller gauge wire in the filament > ckt. Teflon insulation > is best. I'm beginning to think about regulated DC filament supply possibilites for my project amp(s). One of my local 'Elmers' claimed that for 813s, it's a great idea but one needs to periodically reverse the polarity in such a configuration. Thoughts? Many thanks __________________________________________________ Do You Yahoo!? Make a great connection at Yahoo! Personals. http://personals.yahoo.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Mon Oct 29 01:40:03 2001 From: 2@vc.net (2) Date: Sun, 28 Oct 2001 17:40:03 -0800 Subject: [AMPS] Henry 1KD5 Rectifier question Message-ID: <200110290139.f9T1cxZ02120@contesting.com> > >Greetings, > >--- 2 <2@vc.net> wrote: > >> >--- 2 <2@vc.net> wrote: >> > >> >> The 3-500Z is difficult to damage from excessive >> >> grid current because it >> > >> >At ~65 watts drive I get 130ma grid, 450ma plate >> >> 450mA is in the non-linear region of the >> constant-current curves. > >3-500Z curves are one set of curves that I do not >have. I never really intended to do much with this >tube. / At a peak anode/plate current of 1.2a, the 3-500Z is fairly linear. At 1.4a peak, the curve is beginning to substantially deviate from the desired flat line. / notes -- 1.2a peak corresponds to an average current of c. 0.400A. 1.4a peak corresponds to an average current of c. 0.466A. I am sending you a separate e.mail of the constant current curves in gif format. cheers - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Tue Oct 30 09:58:12 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Tue, 30 Oct 2001 09:58:12 -0000 Subject: [AMPS] Henry 1KD5 Rectifier question Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260AA43@excalibur.swindon.msl.mitel.com> Randall said: >I'm beginning to think about regulated DC filament supply possibilites for my project >amp(s). One of my local 'Elmers' claimed that for 813s, it's a great idea but one >needs to periodically reverse the polarity in such a configuration. I've heard this too. One story is some form of electrolysis. I think that a more likely problem would be caused by metal migration. Metal migration in ICs halves for every 12 degree decrease in temperature. It's an exponential function, so it's not so easy to extrapolate from 150 deg C IC temp to the 1600 deg C or so of a thoriated tungsten filament. However, Typical IC metal is rated at about 2mA per micron width: assume 2 micron thick metal, so that's about 2 mA/square micron at 150 deg C. That means 2500 sq microns at the 5Amps of an 813. Guessing at an 813 filament being around .3mm in diameter, that's an area of around 70,000 sq microns. The temperature is more than 10 times as high, so it suggests that metal migration could be the cause of a problem long term. For the military applications where DC was used on the filaments, 500 to 1000 hour operational life frequently exceeded the expected life of the platform on which the radio was fitted...... Dull emitter battery tubes would have been much lower in temperature - 600 deg C - so wouldn't suffer anywhere near as much. Anyone any further comments on this? As far as rectifiers and VOMs are concerned: I don't think anyone makes a single cell that goes above 1200piv. Above that, as far as I'm aware, they are batch matched (at least from the reputable suppliers) cells in series, all in the one package. So the forward drop is 0.7v/cell, and the VOM really needs to be able to source about 1 volt/cell to turn it on. Some of the older VOMs used up to 15 volts on the highest resistance ranges, which was fine. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From g8gsq@qsl.net Wed Oct 31 10:48:03 2001 From: g8gsq@qsl.net (Steve Thompson) Date: Wed, 31 Oct 2001 10:48:03 -0000 Subject: [AMPS] Henry 1KD5 Rectifier question Message-ID: <000601c161f9$853cf480$fd3e7ad5@jackie> -----Original Message----- From: Peter Chadwick To: 2 <2@vc.net>; 1AMPS ; 'Randall DuCharme' Date: 31 October 2001 10:24 Subject: RE: [AMPS] Henry 1KD5 Rectifier question > >Randall said: > >>I'm beginning to think about regulated DC filament supply possibilites for my >project >>amp(s). One of my local 'Elmers' claimed that for 813s, it's a great idea but >one >>needs to periodically reverse the polarity in such a configuration. > >I've heard this too. One story is some form of electrolysis. I think that a more >likely problem would be caused by metal migration. Does it matter (or even does it happen) that you will get more current flow out of the +ve end of the filament? Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Wed Oct 31 11:00:03 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Wed, 31 Oct 2001 11:00:03 -0000 Subject: [AMPS] Henry 1KD5 Rectifier question Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260AA4D@excalibur.swindon.msl.mitel.com> Steve says: >Does it matter (or even does it happen) that you will get more current flow >out of the +ve end of the filament? I suppose it would have some effect, but as the cathode current (as opposed to the filament current) is so much less, I doubt it would make much difference. Reversing the polarity of the filament supply periodically would seem the best way to avoid metal migration problems: an artificial centre tap with a couple of resistors across the filaement for the HV return would be best way to feed the HV return, although they would need to fairly low resistance to avoid the introduction of unwanted cathode bias. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From bjk@ihug.co.nz Wed Oct 31 10:22:49 2001 From: bjk@ihug.co.nz (Barry Kirkwood) Date: Wed, 31 Oct 2001 23:22:49 +1300 Subject: [AMPS] Henry 1KD5 Rectifier question References: <6CEB3A36096CD2119FEE00A0C9410EC20260AA4D@excalibur.swindon.msl.mitel.com> Message-ID: <002901c161f5$febc0020$94d6adcb@ihug.co.nz> Gad, Sir. Anyone who reads QST for 1928 or thereabouts knows that one uses Xmas tree lights to make an artificial filament centre tap! 73 end Barry Kirkwood PhD ZL1DD Signal Hill Homestay 66 Cory Road Palm Beach Waiheke Island 1240 NEW ZEALAND www.waiheke.co.nz/signal.htm ----- Original Message ----- From: Peter Chadwick To: 1AMPS ; 'G8GSQ' Sent: Thursday, 01 November, 2001 12:00 AM Subject: RE: [AMPS] Henry 1KD5 Rectifier question > > Steve says: > > >Does it matter (or even does it happen) that you will get more current > flow > >out of the +ve end of the filament? > > I suppose it would have some effect, but as the cathode current (as opposed to > the filament current) is so much less, I doubt it would make much difference. > Reversing the polarity of the filament supply periodically would seem the best > way to avoid metal migration problems: an artificial centre tap with a couple of > resistors across the filaement for the HV return would be best way to feed the > HV return, although they would need to fairly low resistance to avoid the > introduction of unwanted cathode bias. > > 73 > > Peter G3RZP > > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Wed Oct 31 11:33:25 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Wed, 31 Oct 2001 11:33:25 -0000 Subject: [AMPS] Henry 1KD5 Rectifier question Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260AA4F@excalibur.swindon.msl.mitel.com> Barry said: >Anyone who reads QST for 1928 or thereabouts knows that one uses Xmas tree >lights to make an artificial filament centre tap! they still need to draw a lot of current if they're not to introduce cathode bias! 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k7fm@teleport.com Wed Oct 31 13:40:11 2001 From: k7fm@teleport.com (Lamb) Date: Wed, 31 Oct 2001 05:40:11 -0800 Subject: [AMPS] Henry 1KD5 Rectifier question References: <6CEB3A36096CD2119FEE00A0C9410EC20260AA43@excalibur.swindon.msl.mitel.com> Message-ID: <001e01c16211$91795aa0$200c1ad8@colinlam> I have also heard that dc on the filaments causes migration. It makes sense. However, practicall experience leads me to question whether the conclusion may not be relevant. My old GE Progress Line 2 meter rig was all tubes and it ran on dc. It was in my car for years without replacing any tubes and without reversing polarity of the battery. Finally replaced the Prog Line by little devices that do not have filaments. I have run the tube vfo's in many of my rigs on dc filaments. Left the tube on for years with no failure of the filament. I have never had a failure of a power tube filament - except for one I dropped off the table and one that failed while in the hands of United Parcel Service. So, even if the dc causes premature failure of the filament, it may still outlast the operator or other failure. After all this, would I occassionally change polarity if dc was applied to a filament of an expensive power tube - probably. Colin K7FM -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Wed Oct 31 13:39:28 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Wed, 31 Oct 2001 13:39:28 -0000 Subject: [AMPS] Henry 1KD5 Rectifier question Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260AA53@excalibur.swindon.msl.mitel.com> Coiln said: >So, even if the dc causes premature failure of the >filament, it may still outlast the operator or other failure. I suspect more failures are caused by the stresses when you first switch on and the current is many times normal. Thus the high leakage reactance power transformer is useful. Interestingly, even indirectly heated cathodes have a surge of two or three times when first switched on. How long do tubes last anyway? I'm still using the 6L6G my dad bought in 1936 for what was then 50 cents US. I want his money's worth out of it! 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Douglas.R.Snowden@noaa.gov Wed Oct 31 13:50:54 2001 From: Douglas.R.Snowden@noaa.gov (Douglas R Snowden) Date: Wed, 31 Oct 2001 08:50:54 -0500 Subject: [AMPS] 4CX800 Idle Current a bit high Message-ID: <3BE001BE.B537016B@noaa.gov> I have a 4cx800 that has 350volts screen voltage, -56volts grid bias and 2200volts plate voltage. The specs say it should idle at 150ma. It idles at 200ma. My question is: What is the preferred voltage to adjust to move it to 150ma? Doug N4IJ -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Peter.Chadwick@zarlink.com Wed Oct 31 13:49:20 2001 From: Peter.Chadwick@zarlink.com (Peter Chadwick) Date: Wed, 31 Oct 2001 13:49:20 -0000 Subject: [AMPS] 4CX800 Idle Current a bit high Message-ID: <6CEB3A36096CD2119FEE00A0C9410EC20260AA57@excalibur.swindon.msl.mitel.com> Doug said: >What is the preferred voltage to adjust to move it to 150ma? Whatever it takes. The exact voltage will depend on the gm of that particular tube: I'd expect somewhere around the -60 to -68 volt range. You adjust the bias to get it right - unless you've a number of tubes in parallel, when it gets a little more complicated. Sorry I can't be more exact. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From k7fm@teleport.com Wed Oct 31 14:23:30 2001 From: k7fm@teleport.com (Lamb) Date: Wed, 31 Oct 2001 06:23:30 -0800 Subject: [AMPS] 4CX800 Idle Current a bit high References: <3BE001BE.B537016B@noaa.gov> Message-ID: <008901c16217$9df47ca0$200c1ad8@colinlam> Peter is right on. Since the grid takes very little current, a poteniometer is used to adjust the bias voltage to the exact voltage. Usually you will have a higher negative voltage that is tapped by the poteniometer and you will have fixed resistors on each side of the pot to limit the voltage range. Every time you change tubes, you will need to reset the pot. Although tube manufacturers specify the grid voltage, most manufacturers of grid driven amps specify idle current and have you adjust the bias until you reach a specified idle current. They usually do not care or specify the grid voltage. Whatever it takes is the correct answer. Colin K7FM -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 31 15:50:55 2001 From: 2@vc.net (2) Date: Wed, 31 Oct 2001 07:50:55 -0800 Subject: [AMPS] 4CX800 Idle Current a bit high Message-ID: <200110311549.f9VFniZ01809@contesting.com> > >I have a 4cx800 that has 350volts screen voltage, -56volts >grid bias and 2200volts plate voltage. The specs say it should >idle at 150ma. It idles at 200ma. My question is: > >What is the preferred voltage to adjust to move it to 150ma? > / In Class AB1 gtid-driven service, the screen and/or the grid potential can be used to set ZSAC. To take full advantage of the tube's emissive ability, the screen needs to operated at max rated V. To achieve max linearitty, the grid potential needs to be operated at a neg. potential high enough to result in 0 grid-current with max drive. cheers, Doug - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 31 15:50:57 2001 From: 2@vc.net (2) Date: Wed, 31 Oct 2001 07:50:57 -0800 Subject: [AMPS] Henry 1KD5 Rectifier question Message-ID: <200110311549.f9VFnkZ01813@contesting.com> > >I have also heard that dc on the filaments causes migration. / True with filament type [directly heated] cathodes, but not true with heater type. > It makes >sense. However, practicall experience leads me to question whether the >conclusion may not be relevant. > >My old GE Progress Line 2 meter rig was all tubes and it ran on dc. / My guess is that the tubes used heater type cathodes and not filament type cathodes. >It was >in my car for years without replacing any tubes and without reversing >polarity of the battery. Finally replaced the Prog Line by little devices >that do not have filaments. > >I have run the tube vfo's in many of my rigs on dc filaments. Left the tube >on for years with no failure of the filament. > >I have never had a failure of a power tube filament - except for one I >dropped off the table and one that failed while in the hands of United >Parcel Service. So, even if the dc causes premature failure of the >filament, it may still outlast the operator or other failure. > >After all this, would I occassionally change polarity if dc was applied to a >filament of an expensive power tube - probably. > cheers, Colin - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From 2@vc.net Wed Oct 31 15:51:00 2001 From: 2@vc.net (2) Date: Wed, 31 Oct 2001 07:51:00 -0800 Subject: [AMPS] Henry 1KD5 Rectifier question Message-ID: <200110311549.f9VFnnZ01818@contesting.com> > > >-----Original Message----- >From: Peter Chadwick >To: 2 <2@vc.net>; 1AMPS ; 'Randall DuCharme' > >Date: 31 October 2001 10:24 >Subject: RE: [AMPS] Henry 1KD5 Rectifier question > > >> >>Randall said: >> >>>I'm beginning to think about regulated DC filament supply possibilites for >my >>project >>>amp(s). One of my local 'Elmers' claimed that for 813s, it's a great idea >but >>one >>>needs to periodically reverse the polarity in such a configuration. >> >>I've heard this too. One story is some form of electrolysis. I think that a >more >>likely problem would be caused by metal migration. > >Does it matter (or even does it happen) that you will get more current flow >out of the +ve end of the filament? > / Please explain why, Steve. - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From stevek@jmr.com Wed Oct 31 16:18:06 2001 From: stevek@jmr.com (Steve Katz) Date: Wed, 31 Oct 2001 08:18:06 -0800 Subject: [AMPS] Henry 1KD5 Rectifier question Message-ID: 'Tis true the GE Prog Line and similar 2-way mobile gear from that era used indirectly heated cathodes, mostly receiving tubes with the exception of the PA section, which still used indirectly heated tubes like 6883's, 6146's, etc, depending on the model. I think it was very common for those tubes to be operating at below their normal heater voltage rating, as well...since most of the rigs were trunk-mounted at the far end of 15-20' of cable, away from the battery, and IR drop was pretty high with the rather huge load currents being drawn. WB2WIK/6 "Each success only buys an admission ticket to a more difficult problem." -- Henry Kissinger > -----Original Message----- > From: 2 [SMTP:2@vc.net] > Sent: Wednesday, October 31, 2001 7:51 AM > To: Lamb; Peter Chadwick; 1AMPS; 'Randall DuCharme' > Subject: Re: [AMPS] Henry 1KD5 Rectifier question > > > > > >I have also heard that dc on the filaments causes migration. > > / True with filament type [directly heated] cathodes, but not true with > heater type. > > > It makes > >sense. However, practicall experience leads me to question whether the > >conclusion may not be relevant. > > > >My old GE Progress Line 2 meter rig was all tubes and it ran on dc. > > / My guess is that the tubes used heater type cathodes and not filament > type cathodes. > > >It was > >in my car for years without replacing any tubes and without reversing > >polarity of the battery. Finally replaced the Prog Line by little > devices > >that do not have filaments. > > > >I have run the tube vfo's in many of my rigs on dc filaments. Left the > tube > >on for years with no failure of the filament. > > > >I have never had a failure of a power tube filament - except for one I > >dropped off the table and one that failed while in the hands of United > >Parcel Service. So, even if the dc causes premature failure of the > >filament, it may still outlast the operator or other failure. > > > >After all this, would I occassionally change polarity if dc was applied > to a > >filament of an expensive power tube - probably. > > > cheers, Colin > > - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures. > end > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From wb8jkr@juno.com Wed Oct 31 16:40:53 2001 From: wb8jkr@juno.com (wb8jkr@juno.com) Date: Wed, 31 Oct 2001 11:40:53 -0500 Subject: [AMPS] 4CX800 Idle Current a bit high Message-ID: <20011031.114225.-970879.1.WB8JKR@juno.com> I'd put a 20-25 ohm 20 watt non inductive, non bypassed resistor in series with the cathode. It'll lower your idle current and provide neg. feedback. Mark WB8JKR On Wed, 31 Oct 2001 08:50:54 -0500 "Douglas R Snowden" writes: > > I have a 4cx800 that has 350volts screen voltage, -56volts > grid bias and 2200volts plate voltage. The specs say it should > idle at 150ma. It idles at 200ma. My question is: > > What is the preferred voltage to adjust to move it to 150ma? > > > Doug N4IJ > > > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From oz5tg@post2.tele.dk Wed Oct 31 16:48:28 2001 From: oz5tg@post2.tele.dk (=?iso-8859-1?Q?Verner_Tops=F8e-Jensen_OZ5TG?=) Date: Wed, 31 Oct 2001 17:48:28 +0100 Subject: [AMPS] How to control a vacuum C ?? Message-ID: <008c01c1622b$fc0fe360$c81cfea9@verner3> I am trying to build a controlcircuit for a major PA with an YC156. I am using a pair of Jennings 10-1000PF motordriven capacitors. Problem : The integrated DC-motors requires 18volt to work reliably, but the end-to-endtravel takes only about 3 seconds i.e. 330PF/sec. The controlcircuit has a delay at about 25mSec i.e. the cap. stops 8 - 10 PF off the wanted value. No problem on 160, but on 10, it is a matter of success or failure. The controlcircuit using variable resistors, cannot, even with a very little hysteresis, stop the motors without overshoot. I have tried to chop the DC for the motors. That was an improvement, but far from enough. Any ideas about how to slow down the RPM and maintain the torque ? I checked the Jennings URL, but they do not have any information about how to do. Any help, any idea is welcome. OZ5TG, Verner -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From wc6w@juno.com Wed Oct 31 18:09:47 2001 From: wc6w@juno.com (Radio WC6W) Date: Wed, 31 Oct 2001 10:09:47 -0800 Subject: [AMPS] How to control a vacuum C ?? References: <008c01c1622b$fc0fe360$c81cfea9@verner3> Message-ID: <20011031.100949.15854.1.WC6W@juno.com> On Wed, 31 Oct 2001 17:48:28 +0100 =?iso-8859-1?Q?Verner_Tops=F8e-Jensen_OZ5TG?= writes: > >I am trying to build a controlcircuit for a major PA with an YC156. >I am using a pair of Jennings 10-1000PF motordriven capacitors. > >Problem : >The integrated DC-motors requires 18volt to work reliably, but the >end-to-endtravel takes only about 3 seconds i.e. 330PF/sec. >The controlcircuit has a delay at about 25mSec i.e. the cap. stops >8 - 10 PF off the wanted value. No problem on 160, but on 10, it >is a matter of success or failure. > >The controlcircuit using variable resistors, cannot, even with a very >little >hysteresis, stop the motors without overshoot. > >I have tried to chop the DC for the motors. That was an improvement, >but far from enough. > >Any ideas about how to slow down the RPM and maintain the torque ? > >I checked the Jennings URL, but they do not have any information about > >how to do. > > >Any help, any idea is welcome. > > >OZ5TG, Verner > Hi Verner, When you tried PWM did you include a catch diode(s) across the drive? PWM is the best you are going to do without building a real servo system, including velocity feedback, which will allow for the slow RPM & hi torque you're seeking. Velocity feedback can come either from a tach connected to motor shaft or if that is not easily implemented by calculating the motor speed from the voltage & current seen at the motor terminals. Take a look at the National LMD18200 data sheet -- perhaps on line at: www.national.com 73 & Good evening (by you), Marv WC6W * ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/web/. -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From Ian White, G3SEK" References: <008c01c1622b$fc0fe360$c81cfea9@verner3> <20011031.100949.15854.1.WC6W@juno.com> Message-ID: WC6W wrote: > When you tried PWM did you include a catch diode(s) across the >drive? > Good thought, Marv - the motor will try to keep going until the magnetic field collapses after switch-off. A reverse diode in parallel with the winding(s) will provide a path for the back-EMF, but it can sometimes slow the collapse because the reverse voltage across the coil is clamped to only about 0.7V. The field will collapse faster if the reverse voltage is allowed to rise. A resistor in series with the reverse diode will do this, but a zener diode in series will be even better. The zener breakdown voltage can be about the same as the supply voltage (if the switching transistor can stand twice the normal supply voltage). -- 73 from Ian G3SEK Editor, 'The VHF/UHF DX Book' 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.com/g3sek -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From kc5vdj@yahoo.com Wed Oct 31 21:01:45 2001 From: kc5vdj@yahoo.com (Jim Bryant) Date: Wed, 31 Oct 2001 15:01:45 -0600 Subject: [AMPS] How to control a vacuum C ?? References: <008c01c1622b$fc0fe360$c81cfea9@verner3> Message-ID: <3BE066B9.1090209@yahoo.com> I own both of the MFJ transmitting loops, and their technique seems to work pretty good. For fast tuning, they have a constant positive or negative 12VDC to the cap motor. For fine tuning, they shoot short pulses of the voltage to the cap motor. I'm assuming that the short pulses don't develop enough of a field to keep the motor running for long, but still enough to just bump it in the correct direction. The overshoot is evident at the fast-tuning speed. Also, a zero-backlash motor is crucial to doing things right. 73 de KC5VDJ Verner Tops�e-Jensen OZ5TG wrote: > I am trying to build a controlcircuit for a major PA with an YC156. > I am using a pair of Jennings 10-1000PF motordriven capacitors. > > Problem : > The integrated DC-motors requires 18volt to work reliably, but the > end-to-endtravel takes only about 3 seconds i.e. 330PF/sec. > The controlcircuit has a delay at about 25mSec i.e. the cap. stops > 8 - 10 PF off the wanted value. No problem on 160, but on 10, it > is a matter of success or failure. > > The controlcircuit using variable resistors, cannot, even with a very little > hysteresis, stop the motors without overshoot. > > I have tried to chop the DC for the motors. That was an improvement, > but far from enough. > > Any ideas about how to slow down the RPM and maintain the torque ? > > I checked the Jennings URL, but they do not have any information about > how to do. > > > Any help, any idea is welcome. > > > OZ5TG, Verner > > > -- > FAQ on WWW: http://www.contesting.com/FAQ/amps > Submissions: amps@contesting.com > Administrative requests: amps-REQUEST@contesting.com > Problems: owner-amps@contesting.com > > jim -- ET has one helluva sense of humor! He's always anal-probing right-wing schizos! ----------------------------------------------------- POWER TO THE PEOPLE! ----------------------------------------------------- "Religious fundamentalism is the biggest threat to international security that exists today." United Nations Secretary General B.B.Ghali, 1995 _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From jimr.reid@verizon.net Wed Oct 31 21:57:52 2001 From: jimr.reid@verizon.net (Jim Reid) Date: Wed, 31 Oct 2001 11:57:52 -1000 Subject: [AMPS] Ameritron QSK-5 Message-ID: <001d01c16257$df95d560$a1040304@vz.dsl.genuity.net> Hi, I am considering buying one of these. Concerned my input amp, mechanical relay is being "hot switched", at least at key-up. Have searched diligently for info, but all Ameritron has posted is about the PC card version of this gadget, not the stand alone version in which I am interested. However, as I gather, the keyer plugs into the QSK-5 unit, and the gadget is also connected to your transceiver and the amplifier in such a way that the amp T/R input relay is turned on before the transceiver RF is allowed out; and the amp input T/R relay is turned off only well after the RF from the transceiver has stopped. This should all be done just by sequence timing of the amp relay T/R signal from the transceiver. The transceiver, an Omni VI+, uses a mechanical relay to signal the amp's T/R switching relays. Figure at least 10 ms for this relay to operate. Then RF output appears less than 5 ms after the contact closure since per the ARRL lab tests, my Omni keying has about a 15msec delay between key down and RF output, and 17 msec delay between key up and the RF stopping. 5 to 7 milliseconds is less time than the amp Guardian input relay needs to operate. Therefore when the input relay contact opens, it is carrying RF current, and so it will arc as it opens. Every time. My only concern is the input T/R relay; I believe the output vacuum relay in my amp is fast enough as I do not use "full QSK" timing, that is switch the relays between every dit. My output relay is a Jennings R2B, SPDT, 26 vdc unit. The Guardian input relay is not as fast, so my concern. I have already had to replace it once. Can I use the QSK-5 to only control this input, or must it be set up to switch both amp input and output ports. My concern about the unit also being in series with the output is that, in a couple of places (but not in the Ameritron info I have found on the web) it is said that you must fan cool the QSK-5 if you are going to use amateur legal output powers! 73, Jim KH7M -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com From ve3tu@rac.ca Wed Oct 31 23:05:41 2001 From: ve3tu@rac.ca (Steve) Date: Wed, 31 Oct 2001 23:05:41 +0000 Subject: [AMPS] How to control a vacuum C ?? References: <008c01c1622b$fc0fe360$c81cfea9@verner3> Message-ID: <3BE083C5.116529DE@rac.ca> One of the ways to slow down a dc motor fast is with an H bridge mosfet cct. You can have forward, reverse and brake functions. The H bridge slows down the motor a lot faster than a diode, I tried it on a model airplane electric motor and the diode made almost no difference at all in the slow down rate but with the H bridge the motor comes to quick stop. You could also put in a feed back pot and slow down the pulses when the cap. gets close to the right position. gl es 73 Steve -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com