Ok - so why don't we take a page out of the software world, and collaborate
to design a high quality 1500 watt key down solid state HF amplifier?
I'd build one if a couple of capable hams (which definition sadly excluses
me) would would design it...
***dan, K6IF
----- Original Message -----
From: <amps-request@contesting.com>
To: <amps@contesting.com>
Sent: Monday, March 03, 2003 4:42 PM
Subject: Amps Digest, Vol 3, Issue 10
> Send Amps mailing list submissions to
> amps@contesting.com
>
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> or, via email, send a message with subject or body 'help' to
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> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of Amps digest..."
>
>
> Today's Topics:
>
> 1. Re: hear hear about the toobs (2)
> 2. Solidstate amps (Jeffrey Madore)
> 3. Re: Why hasn't solid state replaced tubes? (Zyg Skrobanski)
> 4. Re: Why hasn't solid state replaced tubes? (Tom Rauch)
> 5. Re: Why hasn't solid state replaced tubes? (Tom Rauch)
> 6. Re: Why hasn't solid state replaced tubes? (Zyg Skrobanski)
> 7. Re: Why hasn't solid state replaced tubes?
> 8. RE: AL-80B questions (Conrad G0RUZ)
> 9. RE: AL-80B questions (2)
> 10. RE: Solidstate amps (Conrad G0RUZ)
>
>
> ----------------------------------------------------------------------
>
To: <amps@contesting.com>
> Date: Mon, 3 Mar 2003 11:15:14 -0800
> From: 2 <2@vc.net>
> To: "Keith LaBorde - K4KAL" <k4kal@arrl.net>, " AMPS"
<amps@contesting.com>
> Subject: Re: [Amps] hear hear about the toobs
> Message-ID: <200303031925.h23JP72O029322@contesting.com>
> Content-Type: text/plain; charset="US-ASCII"
> MIME-Version: 1.0
> Precedence: list
> Message: 1
>
>
>
> >Hello Group !
> >
> >I have been following the discussion on tubes and I find it very
> >interesting.
> >I am in no way an expert, but have had my share of 8877's, 3-500Z's.
> >
> >I can say I did experience a problem with a 8877 in an old Ameritron
AL-1500
> >I had some years ago, and replaced it with a "Pull" that I purchased
> >and was back on the air. I did not have the skill to check the tube
> >to even know if it was bad. I figured since it had lower then expected
> >output, it was time to go.
>
> ** Low P-out is a symptom of gold-sputtering - wherein gold evaporates
> from the grid and lands on the cathode. Since the gold poisons cathode
> emission, which lowers I-anode and power output.
> - I would like to test the tube you pulled and try to find out what's
> what. I will return tube via Priority Mail. If the problem is
> gold-related, it is not difficult to move the gold particles from the
> cathode into the tube base by tapping with a hammer in the vertical
> plane. This restores emission and the tube can be used as a spare
> provided the base is down.
> - An autopsy photo of a gold sputtered 8877 removed from an AL-1500:
> http://WWW.VCNET.COM/measures/8877.gs2.JPEG
> The Funderburg (W6IHA) gold sputter test is described on my Web site.
>
> cheerz, Keith
> >
> >I am curious is some of the problems in the past that have made company's
> >switch to the Russian Tubes, are do they also have similar problems.
> >
> >I own 2 Alpha-99 Amplifers, and have been gradually accumulating
> >4CX800's as spares with the fear that in the future when I need
> >some they will be expensive to purchase, or not available.
> >
> >Would appreciate any comments on my strategy of purchasing
> >tubes and putting them in storage.
> >
> >Thanks,
> >Keith, K4KAL
> >
> >
> >
> >_______________________________________________
> >Amps mailing list
> >Amps@contesting.com
> >http://lists.contesting.com/mailman/listinfo/amps
> >
>
>
> - R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
> www.vcnet.com/measures.
> end
>
> ------------------------------
>
To: <amps@contesting.com>
> Date: Mon, 3 Mar 2003 14:29:42 -0500
> From: "Jeffrey Madore" <K1LE@ARRL.NET>
> To: <AMPS@contesting.com>
> Subject: [Amps] Solidstate amps
> Message-ID: <001601c2e1bb$3d78b510$e8c8d442@Office>
> Content-Type: text/plain;
> charset="iso-8859-1"
> MIME-Version: 1.0
> Content-Transfer-Encoding: quoted-printable
> Precedence: list
> Message: 2
>
> The audio folks are doing it. 2200W Bridge mono into 8 ohms...21Lbs!...2 =
> rack spaces!
> Qsc has a good reputation too.
>
> http://www.qscaudio.com/products/amps/plx/plx.htm
>
> Has anyone looked at the drawbacks / advantages of a HV switching =
> powersupply? Just curious...
>
> Jeff - K1LE ><>From w8ji@contesting.com Mon Mar 3 14:57:35 2003
> Received: from paris.akorn.net (paris.akorn.net [216.1.128.10])
> by contesting.com (8.12.2/8.12.2) with ESMTP id h23JvZ2O025094
> for <amps@contesting.com>; Mon, 3 Mar 2003 14:57:35 -0500
> Received: from w8ji (216-1-128-63.akorn.net [216.1.128.63])
> by paris.akorn.net (8.11.6/8.11.0) with SMTP id h23JvYr10334
> for <amps@contesting.com>; Mon, 3 Mar 2003 14:57:34 -0500
> Message-ID: <002a01c2e1bf$0b3326e0$348001d8@akorn.net>
> From: "Tom Rauch" <w8ji@contesting.com>
> To: "Amps Amps" <amps@contesting.com>
To: <amps@contesting.com>
> Date: Mon, 3 Mar 2003 14:56:54 -0500
> MIME-Version: 1.0
> Content-Type: text/plain;
> charset="iso-8859-1"
> Content-Transfer-Encoding: 7bit
> X-Priority: 3
> X-MSMail-Priority: Normal
> X-Mailer: Microsoft Outlook Express 6.00.2800.1106
> X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106
> Subject: [Amps] Tank Circuit (was toroid) model
> X-BeenThere: amps@contesting.com
> X-Mailman-Version: 2.1
> Precedence: list
> Reply-To: Tom Rauch <w8ji@contesting.com>
> List-Id: <amps.contesting.com>
> List-Unsubscribe: <http://lists.contesting.com/mailman/listinfo/amps>,
> <mailto:amps-request@contesting.com?subject=unsubscribe>
> List-Archive: <http://dayton.akorn.net/pipermail/amps>
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> List-Subscribe: <http://lists.contesting.com/mailman/listinfo/amps>,
> <mailto:amps-request@contesting.com?subject=subscribe>
>
> I put a model of a tank up for anyone interested in tank Q, phase shift,
and
> the inductor voltage.
>
> http://www.w8ji.com/tank_circuit.htm
>
> This shows how phase shift is related to Q, and how inductor voltage
exceeds
> input voltage, and how increasing Q (even with a slightly decreased input
> voltage) increase voltages and currents!
>
> I hope this makes the circuit clearer, and show how phase shift across the
> inductor is not 90-degrees (except in the case of a minimal Q network of
> course, which would behave like a 1/4 wl transmission line).
>
> 73 Tom
>
> ------------------------------
>
To: <amps@contesting.com>
> Date: Mon, 03 Mar 2003 15:05:56 -0500
> From: Zyg Skrobanski <af4mp@mindspring.com>
> To: amps@contesting.com
> Subject: Re: [Amps] Why hasn't solid state replaced tubes?
> Message-ID: <3.0.6.32.20030303150556.00a6e6c8@pop.mindspring.com>
> In-Reply-To: <5.2.0.9.2.20030303104641.01b98600@pop.dc2.adelphia.net>
> References: <p05210500ba8919f1cbf1@[128.165.34.51]>
> Content-Type: text/plain; charset="us-ascii"
> MIME-Version: 1.0
> Precedence: list
> Message: 3
>
> At 10:53 AM 3/3/03 -0500, you wrote:
>
> >This all makes sense to me, but I was a little uncertain about Tom's
> >comments about tubes being on the way out.
>
> All new AM broadcast transmitters are now solid state, as well as many FM
> and TV transmitters too.
>
> >that high-power solid state amplifiers for amateur use haven't come very
> >far since (pardon the phonetic spelling) Helge Granberg's cover article
in
> >QST maybe 25 years ago.
>
> Please check out R. F. Electronics at:
>
> http://users.aol.com/rfelectron/rfelect.htm
> --
> Zyg AF4MP
> Roswell GA USA
>
> ------------------------------
>
To: <amps@contesting.com>
> Date: Mon, 3 Mar 2003 15:09:33 -0500
> From: "Tom Rauch" <w8ji@contesting.com>
> To: <n4zr@contesting.com>, <amps@contesting.com>, "Radio WC6W"
<wc6w@juno.com>
> Subject: Re: [Amps] Why hasn't solid state replaced tubes?
> Message-ID: <004201c2e1c0$cf9ae300$348001d8@akorn.net>
> References: <20030303.093549.-1903391.0.WC6W@juno.com>
> Content-Type: text/plain;
> charset="iso-8859-1"
> MIME-Version: 1.0
> Content-Transfer-Encoding: 7bit
> Precedence: list
> Reply-To: Tom Rauch <w8ji@contesting.com>
> Message: 4
>
> > For 1500 watts out it would take say... 4 - MRF154's. Those probably
> > would cost at least $1000 at an OEM level,
>
> It is less expensive and more reliable to use multiple MRF150's.
>
> First, heat is spread out over a larger area.
>
> Second, the RF layout would be better
>
> Third, cost goes down because component quantities increase
>
> Last time I looked at wholesale cost, I could buy 20 MRF150's for $1000.
>
> 73 Tom
> ------------------------------
>
To: <amps@contesting.com>
> Date: Mon, 3 Mar 2003 15:12:33 -0500
> From: "Tom Rauch" <w8ji@contesting.com>
> To: <amps@contesting.com>, "Zyg Skrobanski" <af4mp@mindspring.com>
> Subject: Re: [Amps] Why hasn't solid state replaced tubes?
> Message-ID: <004b01c2e1c1$3a8f4200$348001d8@akorn.net>
> References: <p05210500ba8919f1cbf1@[128.165.34.51]>
> <3.0.6.32.20030303150556.00a6e6c8@pop.mindspring.com>
> Content-Type: text/plain;
> charset="iso-8859-1"
> MIME-Version: 1.0
> Content-Transfer-Encoding: 7bit
> Precedence: list
> Reply-To: Tom Rauch <w8ji@contesting.com>
> Message: 5
>
> > Please check out R. F. Electronics at:
> >
> > http://users.aol.com/rfelectron/rfelect.htm
> > --
>
>
> But those are not good amps at all!
>
> They are dirty low-voltage bipolar amps and the devices are pushed pretty
> hard. They would never be acceptable for anything but low-power mobile, or
> FM or CW. Same with CB amps.
>
> For use at home on large antennas, -20dB IM3 is intolerable.
>
> 73 Tom
>
> ------------------------------
>
To: <amps@contesting.com>
> Date: Mon, 03 Mar 2003 15:20:23 -0500
> From: Zyg Skrobanski <af4mp@mindspring.com>
> To: "Tom Rauch" <w8ji@contesting.com>, amps@contesting.com
> Subject: Re: [Amps] Why hasn't solid state replaced tubes?
> Message-ID: <3.0.6.32.20030303152023.00a6e6c8@pop.mindspring.com>
> In-Reply-To: <004b01c2e1c1$3a8f4200$348001d8@akorn.net>
> References: <p05210500ba8919f1cbf1@[128.165.34.51]>
> <3.0.6.32.20030303150556.00a6e6c8@pop.mindspring.com>
> Content-Type: text/plain; charset="us-ascii"
> MIME-Version: 1.0
> Precedence: list
> Message: 6
>
> At 03:12 PM 3/3/03 -0500, you wrote:
> >> Please check out R. F. Electronics at:
> >
> >But those are not good amps at all!
> >
> >For use at home on large antennas, -20dB IM3 is intolerable.
>
> Ouch, my apologies, I didn't know they were that bad!
>
>
> --
> Zyg AF4MP
> Roswell GA USA
>
> ------------------------------
>
To: <amps@contesting.com>
> Date: Mon, 3 Mar 2003 15:42:22 -0500
> From: wb8jkr@juno.com
> To: af4mp@mindspring.com
> Cc: amps@contesting.com
> Subject: Re: [Amps] Why hasn't solid state replaced tubes?
> Message-ID: <20030303.154222.-297455.2.wb8jkr@juno.com>
> Content-Type: text/plain
> MIME-Version: 1.0
> Content-Transfer-Encoding: 7bit
> Precedence: list
> Message: 7
>
>
> Not a whole lot worse than some of the rigs on
> the market today, unfortunately.
>
> Mark WB8JKR
>
>
> On Mon, 03 Mar 2003 15:20:23 -0500 Zyg Skrobanski <af4mp@mindspring.com>
> writes:
> > At 03:12 PM 3/3/03 -0500, you wrote:
> > >> Please check out R. F. Electronics at:
> > >
> > >But those are not good amps at all!
> > >
> > >For use at home on large antennas, -20dB IM3 is intolerable.
> >
> > Ouch, my apologies, I didn't know they were that bad!
> >
>
>
> ________________________________________________________________
> Sign Up for Juno Platinum Internet Access Today
> Only $9.95 per month!
> Visit www.juno.com
> ------------------------------
>
To: <amps@contesting.com>
> Date: Mon, 3 Mar 2003 23:14:48 -0000
> From: "Conrad G0RUZ" <conrad@g0ruz.net>
> To: "AMPS" <amps@contesting.com>, "2" <2@vc.net>
> Subject: RE: [Amps] AL-80B questions
> Message-ID: <KGECLDDCJAGJEAKACLMMEEEOEIAA.conrad@g0ruz.net>
> In-Reply-To: <E18pXWp-0000uB-00@ultra24.uk2net.com>
> Content-Type: text/plain;
> charset="us-ascii"
> MIME-Version: 1.0
> Content-Transfer-Encoding: 7bit
> Precedence: list
> Reply-To: conrad@g0ruz.net
> Message: 8
>
> Of course Rich it works very well, especially on this old chestnut! It
> reminds me of the re-runs we have on BBC TV in the UK.
>
> Still I must admit without you having a dig at Tom when he surfaces, I
would
> begin to worry. As I approach middle age, it's nice to know that some
things
> in life are dependable :-)
>
> Conrad
>
> -----Original Message-----
> From: 2 [mailto:2@vc.net]
> Sent: 02 March 2003 17:36
> To: conrad@g0ruz.net
> Subject: RE: [Amps] AL-80B questions
>
>
> Conrad -- Does your Delete button work?
>
> >Here we go again (GROANNNNNNNNNNNNNNNN.............)
> >
> >Conrad G0RUZ
> >
> >-----Original Message-----
> >From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]On
> >Behalf Of 2
> >Sent: 02 March 2003 12:30
> >To: Tom Rauch; AMPS
> >Subject: Re: [Amps] AL-80B questions
> >
> >
> >
> >
> >>
> >>>
> >>> 1: Does this sound like a symptom of parasitic oscillations?
> >>> I thought the 3-500Z was pretty rugged with respect to faults.
> >>
> >>Parasitics, even assuming they would occur, can't cause tube failures
> >unless
> >>you see some solid evidence of excessive current on meters.
> >>
> >A jump to 250mA of ZSAC is not a clue?
> >
> >>I don't know what time period you are talking about, but I've had
several
> >>Amperex 3-500Z's fail in my own equipment. Amperex, like all foreign
tube
> >>companies, is a bit difficult to work with. My last conversations with
> >>Amperex were only through Richardsons Electronics(who owns Amperex), and
> >>involved 3-500Z grid-to-filament shorts.
> >>
> >>I had four 3-500Z tubes in a test fixture cycling only the filament
> >>off-and-on once every minute, and within a day two tubes failed. In a
week
> >>they were all bad. All of them failed because the center of the filament
> >>helice moved over and touched the grid.
> >>
> >>My conclusion is the repeated thermal cycling of the filament, and a
> >>material or assembly flaw in the tube, caused the helice to move the few
> >>thousands of an inch required to cause a short.
> >>
> >It takes more movement than this to short a 3-500Z.
> >
> >>> 2: Does anyone know of any problems with recently built Amperex
bottles?
> >>
> >>Absolutely there are.
> >>
> >But Tom Rauch is apparently the only person on this planet who is
> >convinced of this.
> >
> >>> 3: I'll probably help him install the parasitic supressor kit
somethime
> >>>this week. Are there any other things to look for or suggested
> >corrections
> >>>to this thing that would make it less prone to eating another tube?
> >>
> >>Put a dead-chicken leg over the cabinet, and say a prayer instead. It
will
> >>be more effective.
> >>
> >The recognized amplifier expert plays the Ad Hominem Card.
> >
> >>Seriously, ask him how much often he cycles the amp on and off. Also be
> >sure
> >>voltages are set correctly on the power transformer taps, and that there
> is
> >>no error in filament voltage. Ameritron's transformer vendor,
Schumacher,
> >>moved to Mexico about a year or so ago and transformer quality was
> suddenly
> >>horrible. Bad connections were the least of the problems (it looked like
> >>they soldered transformers with a hot rock), there were also some build
> >>problems in transformers.
> >
> >Say what ?
> >>
> >>I'd assume Ameritron measured filament voltage at the tube, but they
might
> >>not have measured it correctly or with a good meter.
> >
> >So is Tom Rauch still employed by Martin F. Jue ?
> >
> >> The quality of
> >>technical people is dropping like a rock as time passes. I'd re-measure
> the
> >>filament voltage, especially in light of the nature of tube failures.
> >>
> >Grid-fil shorts from too much filament V ?
> >
> >>Make sure your friend isn't needlessly cycling the filament off-and-on,
> >>since the failures are on-and-off cycle related in tests I have done. I
> >knew
> >>a guy who ate 3CX1200D7's in a Henry like pop-corn because he cycled the
> >>filament off and on about ten times a day. He'd get about two months on
a
> >>tube.
> >>
> >The 3cx1200D7 has no spec on fil inrush current.
> >
> >>Remember you are dealing with a white-hot filament
> >
> >1830 degrees K is hardly white hot.
> >
> >>that has one common
> >>mechanical support point *at the very bottom*.
> >
> >There's a ceramic support at the top of the filament.
> >
> >>The filament is about 2-3
> >>inches long when wound in a tight helice, and is thousands of an inch
from
> >>the grid. Even if the tube is built properly, it isn't a good idea to
> >>heat-cycle the filament needlessly.
> >>
> >>Ask him how often he turns it on and off BEFORE you tell him anything
> else,
> >>and see if it is abnormal. Also be sure he knows to keep operating grid
> >>current below 125-150mA on carrier.
> >>
> >Eimac has no such advice in the specs.
> >
> >>73 Tom
> >
> >- R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
> >www.vcnet.com/measures.
> >end
> >
> >_______________________________________________
> >Amps mailing list
> >Amps@contesting.com
> >http://lists.contesting.com/mailman/listinfo/amps
> >
> >
> >_______________________________________________
> >Amps mailing list
> >Amps@contesting.com
> >http://lists.contesting.com/mailman/listinfo/amps
> >
>
>
> - R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
> www.vcnet.com/measures.
> end
>
>
>
> ------------------------------
>
To: <amps@contesting.com>
> Date: Mon, 3 Mar 2003 15:25:46 -0800
> From: 2 <2@vc.net>
> To: <conrad@g0ruz.net>, " AMPS" <amps@contesting.com>
> Subject: RE: [Amps] AL-80B questions
> Message-ID: <200303032335.h23NZc2O028953@contesting.com>
> Content-Type: text/plain; charset="US-ASCII"
> MIME-Version: 1.0
> Precedence: list
> Message: 9
>
>
>
> >Of course Rich it works very well, especially on this old chestnut! It
> >reminds me of the re-runs we have on BBC TV in the UK.
> >
> >Still I must admit without you having a dig at Tom when he surfaces, I
would
> >begin to worry.
>
> When Tom finally admits that AC circuit analysis is valid for vhf
> suppressors, that more than 20w is needed to boil gold from a 50g grid,
> and when he admits that Ni-Cr alloys have more R as freq increases, then
> the party is winding down.
>
> Have phun
>
> >As I approach middle age, it's nice to know that some things
> >in life are dependable :-)
> >
> >Conrad
> >
> >-----Original Message-----
> >From: 2 [mailto:2@vc.net]
> >Sent: 02 March 2003 17:36
> >To: conrad@g0ruz.net
> >Subject: RE: [Amps] AL-80B questions
> >
> >
> >Conrad -- Does your Delete button work?
> >
> >>Here we go again (GROANNNNNNNNNNNNNNNN.............)
> >>
> >>Conrad G0RUZ
> >>
> >>-----Original Message-----
> >>From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]On
> >>Behalf Of 2
> >>Sent: 02 March 2003 12:30
> >>To: Tom Rauch; AMPS
> >>Subject: Re: [Amps] AL-80B questions
> >>
> >>
> >>
> >>
> >>>
> >>>>
> >>>> 1: Does this sound like a symptom of parasitic oscillations?
> >>>> I thought the 3-500Z was pretty rugged with respect to faults.
> >>>
> >>>Parasitics, even assuming they would occur, can't cause tube failures
> >>unless
> >>>you see some solid evidence of excessive current on meters.
> >>>
> >>A jump to 250mA of ZSAC is not a clue?
> >>
> >>>I don't know what time period you are talking about, but I've had
several
> >>>Amperex 3-500Z's fail in my own equipment. Amperex, like all foreign
tube
> >>>companies, is a bit difficult to work with. My last conversations with
> >>>Amperex were only through Richardsons Electronics(who owns Amperex),
and
> >>>involved 3-500Z grid-to-filament shorts.
> >>>
> >>>I had four 3-500Z tubes in a test fixture cycling only the filament
> >>>off-and-on once every minute, and within a day two tubes failed. In a
week
> >>>they were all bad. All of them failed because the center of the
filament
> >>>helice moved over and touched the grid.
> >>>
> >>>My conclusion is the repeated thermal cycling of the filament, and a
> >>>material or assembly flaw in the tube, caused the helice to move the
few
> >>>thousands of an inch required to cause a short.
> >>>
> >>It takes more movement than this to short a 3-500Z.
> >>
> >>>> 2: Does anyone know of any problems with recently built Amperex
bottles?
> >>>
> >>>Absolutely there are.
> >>>
> >>But Tom Rauch is apparently the only person on this planet who is
> >>convinced of this.
> >>
> >>>> 3: I'll probably help him install the parasitic supressor kit
somethime
> >>>>this week. Are there any other things to look for or suggested
> >>corrections
> >>>>to this thing that would make it less prone to eating another tube?
> >>>
> >>>Put a dead-chicken leg over the cabinet, and say a prayer instead. It
will
> >>>be more effective.
> >>>
> >>The recognized amplifier expert plays the Ad Hominem Card.
> >>
> >>>Seriously, ask him how much often he cycles the amp on and off. Also be
> >>sure
> >>>voltages are set correctly on the power transformer taps, and that
there
> >is
> >>>no error in filament voltage. Ameritron's transformer vendor,
Schumacher,
> >>>moved to Mexico about a year or so ago and transformer quality was
> >suddenly
> >>>horrible. Bad connections were the least of the problems (it looked
like
> >>>they soldered transformers with a hot rock), there were also some build
> >>>problems in transformers.
> >>
> >>Say what ?
> >>>
> >>>I'd assume Ameritron measured filament voltage at the tube, but they
might
> >>>not have measured it correctly or with a good meter.
> >>
> >>So is Tom Rauch still employed by Martin F. Jue ?
> >>
> >>> The quality of
> >>>technical people is dropping like a rock as time passes. I'd re-measure
> >the
> >>>filament voltage, especially in light of the nature of tube failures.
> >>>
> >>Grid-fil shorts from too much filament V ?
> >>
> >>>Make sure your friend isn't needlessly cycling the filament off-and-on,
> >>>since the failures are on-and-off cycle related in tests I have done. I
> >>knew
> >>>a guy who ate 3CX1200D7's in a Henry like pop-corn because he cycled
the
> >>>filament off and on about ten times a day. He'd get about two months on
a
> >>>tube.
> >>>
> >>The 3cx1200D7 has no spec on fil inrush current.
> >>
> >>>Remember you are dealing with a white-hot filament
> >>
> >>1830 degrees K is hardly white hot.
> >>
> >>>that has one common
> >>>mechanical support point *at the very bottom*.
> >>
> >>There's a ceramic support at the top of the filament.
> >>
> >>>The filament is about 2-3
> >>>inches long when wound in a tight helice, and is thousands of an inch
from
> >>>the grid. Even if the tube is built properly, it isn't a good idea to
> >>>heat-cycle the filament needlessly.
> >>>
> >>>Ask him how often he turns it on and off BEFORE you tell him anything
> >else,
> >>>and see if it is abnormal. Also be sure he knows to keep operating grid
> >>>current below 125-150mA on carrier.
> >>>
> >>Eimac has no such advice in the specs.
> >>
> >>>73 Tom
> >>
> >>- R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
> >>www.vcnet.com/measures.
> >>end
> >>
> >>_______________________________________________
> >>Amps mailing list
> >>Amps@contesting.com
> >>http://lists.contesting.com/mailman/listinfo/amps
> >>
> >>
> >>_______________________________________________
> >>Amps mailing list
> >>Amps@contesting.com
> >>http://lists.contesting.com/mailman/listinfo/amps
> >>
> >
> >
> >- R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
> >www.vcnet.com/measures.
> >end
> >
> >
> >
> >
>
>
> - R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
> www.vcnet.com/measures.
> end
>
> ------------------------------
>
To: <amps@contesting.com>
> Date: Mon, 3 Mar 2003 23:47:13 -0000
> From: "Conrad G0RUZ" <conrad@g0ruz.net>
> To: <AMPS@contesting.com>
> Subject: RE: [Amps] Solidstate amps
> Message-ID: <KGECLDDCJAGJEAKACLMMAEEPEIAA.conrad@g0ruz.net>
> In-Reply-To: <001601c2e1bb$3d78b510$e8c8d442@Office>
> Content-Type: text/plain;
> charset="iso-8859-1"
> MIME-Version: 1.0
> Content-Transfer-Encoding: 7bit
> Precedence: list
> Reply-To: conrad@g0ruz.net
> Message: 10
>
> This technology has been around for quite a while in Pro Audio, I believe
> that Carver were the first, QSC are very well proven but the very best are
> Lab Gruppen, I took 10kW of this stuff on the road once and I could lift
the
> rack on my own! Of course as we all know audio has a whole different
> perspective and a different set of problems.
>
> One day this will surely come to us...........
>
> 73
>
> Conrad G0RUZ
>
> -----Original Message-----
> From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]On
> Behalf Of Jeffrey Madore
> Sent: 03 March 2003 19:30
> To: AMPS@contesting.com
> Subject: [Amps] Solidstate amps
>
>
> The audio folks are doing it. 2200W Bridge mono into 8 ohms...21Lbs!...2
> rack spaces!
> Qsc has a good reputation too.
>
> http://www.qscaudio.com/products/amps/plx/plx.htm
>
> Has anyone looked at the drawbacks / advantages of a HV switching
> powersupply? Just curious...
>
> Jeff - K1LE ><>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
>
> ------------------------------
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
>
> End of Amps Digest, Vol 3, Issue 10
> ***********************************
>
|
