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Re: [Amps] Amps Digest, Vol 97, Issue 37

To: <amps@contesting.com>
Subject: Re: [Amps] Amps Digest, Vol 97, Issue 37
From: "K5MA" <k5ma@comcast.net>
Reply-to: K5MA <k5ma@comcast.net>
Date: Mon, 24 Jan 2011 11:46:37 -0500
List-post: <amps@contesting.com">mailto:amps@contesting.com>
Does anyone subscribed to the 'amps' list know anyone in New England 
(Eastern MA preferred) who might be proficient at rebuilding the worn and 
damaged mechanical parts in my old Henry 3K amplifier?  The electrical parts 
are easy to work on and replace, but the mechanical parts need lots of work. 
Any help from this list will be greatly appreciated.

73 de K5MA
K5MA@arrl.net

Jan Carman, K5MA
P. O. Box 930
West Falmouth, MA  02574-0930

k5ma@arrl.net
k5ma@comcast.net
jancarmanj@alumni.upenn.edu


-----Original Message----- 
From: amps-request@contesting.com
Sent: Saturday, January 22, 2011 6:21 AM
To: amps@contesting.com
Subject: Amps Digest, Vol 97, Issue 37

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Today's Topics:

   1. Re: AL-811 & 572's (Alek Petkovic)
   2. Re: Help with HL2200 6 meter conversion (Gary Myers)
   3. Re: Help with HL2200 6 meter conversion (Dick Hanson)
   4. Re: Fireing up a old Tl922 amplifier. (Mike Tubby)
   5. Re: Help with HL2200 6 meter conversion (Vic K2VCO)


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

Message: 1
Date: Sat, 22 Jan 2011 04:41:10 +0800
From: Alek Petkovic <vk6apk@bigpond.com>
Subject: Re: [Amps] AL-811 & 572's
To: "Thomas F. Giella NZ4O" <nz4o@tampabay.rr.com>, "amps @ COL"
<amps@contesting.com>
Message-ID:
<20110121204114.VLKS781.nschwotgx04p.mx.bigpond.com@binningup.bigpond.com>

Content-Type: text/plain; charset="us-ascii"; format=flowed

The transformer is the limiting factor just as much as the tubes. You
can't run the 572Bs any harder because you'll just cook the transformer.

73, Alek
VK6APK

At 01:50 AM 22/01/2011, Thomas F. Giella NZ4O wrote:
>I have an AL-811 running 572B's instead of 811's. The manual says for RTTY
>mode to use a maximum of 150 ma on the grid and 400 ma on the plate for the
>811's.
>
>What would be the maximum grid and plate current that I could use on the
>572B's on RTTY?
>
>73 & GUD DX,
>Thomas F. Giella, NZ4O
>Lakeland, FL, USA
>nz4o@tampabay.rr.com
>
>NZ4O Solar Space Weather And Geomagnetic Data Archive: http://www.nz4o.org
>NZ4O Daily LF/MF/HF/6M Radiowave Propagation Forecast:
>http://www.solarcycle24.org
>
>
>_______________________________________________
>Amps mailing list
>Amps@contesting.com
>http://lists.contesting.com/mailman/listinfo/amps
>
>
>
>
>=======
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>From sunny Binningup, Western Australia

http://www.qrz.com/db/vk6apk
http://www.qrz.com/db/vk6ap





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

Message: 2
Date: Fri, 21 Jan 2011 21:13:38 -0700
From: "Gary Myers" <garymyers@powerc.net>
Subject: Re: [Amps] Help with HL2200 6 meter conversion
To: "Amps" <amps@contesting.com>
Message-ID: <518E92F2AF704D37A1D931FA5024FC46@GaryPC>
Content-Type: text/plain; charset="iso-8859-1"

Hello....

I've just completed converting a Heathkit HL2200 amp, stripping all the tank 
out as well as the input ckt. I left the existing plate tuning cap in and am 
using it as the load cap. The plate tuning cap, now where the load cap was, 
is a 100pf variable. This was all down according to an April '08 article on 
the same. The input is a T network and it by the way works perfectly with a 
1:1 SWR.

The suppressors are as the article says - nichrome ribbon, 1/4" wide formed 
into a U with 3 2W carbon resistors in parallel at its base. All soldered 
using silver solder for the nichrome. All seemed to go fine.

After installing the tank components I used a dip meter to try and see if 
the tank coil was set right. I first confirmed the meter setting by checking 
it on a radio set to 50.1Mhz... and then tried to insert its coil into the 
limited area of the tank coil... it measured 60Mhz! So I squeezed the turns 
together - it dropped to 54Mhz... I decided to leave it as is and wait until 
I could power it up.

When I first tried to run it I was only able to get about 60W out with about 
20W drive and the plate tune cap was at its minimum setting... I believe 
this indicates that indeed the coil is too much inductance (does it not?) 
and so I pulled the turns apart as best I could. This allowed me to get 
about 350W out (with about 840W in) with maybe 35W drive (I didn't measure 
this by itself - just going by where I had the power set on the 746Pro). But 
very quickly, before I could increase the input, it started to smell! The 
carbon resistors were getting VERY hot.

I quickly removed the cover (obviously made sure the HV was 0) and with a 
thermal gun checked the temperature of the suppression resistors - one set 
was at about 160 deg and the other set about 125 degrees. One resistor in 
the one set appears to be higher than the others - but this might just be 
the difficulty in checking with a thermal gun.

So my question is: WHY are these getting hot?! I would have thought, if the 
article said use these resistors, that it would work fine. The U nichrome 
wire is almost identical to the one they have pictured (mechanical picture 
for scale) in the article. Note I couldn't find the 150 ohm resistors they 
said - I used 3 180 ohm resistors - but I find it impossible to believe that 
it would work with 50 ohms eqv and not 60 ohms eqv nor that the 60 ohm eqv 
should dissipate MORE power, not less.

I'm also a bit troubled by the efficiency... but until I get this resolved 
I'm not going to worry too much about this - however if someone things it is 
related I'd love to hear it.

Thanks for your time.

Gary
K9RX

[the amp was bought from someone that said it had been converted to 6 meters 
replacing the 10 position and the other bands still there... it didn't work 
on 6 which didn't make me happy so I decided to rip it all out and just make 
it a 6 only amp... note however it would put out about 1150W on 20 meters 
before the change.]

ps: Also note that when I remove the cover (the HV short is disabled) I get 
550W out with about 800W in but now the load cap is at its maximum value!



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

Message: 3
Date: Sat, 22 Jan 2011 04:17:41 -0600
From: "Dick Hanson" <dick@dkhanson.com>
Subject: Re: [Amps] Help with HL2200 6 meter conversion
To: "'Gary Myers'" <garymyers@powerc.net>
Cc: amps@contesting.com
Message-ID: <000a01cbba1d$9a604750$cf20d5f0$@com>
Content-Type: text/plain; charset="us-ascii"

Morning, Gary.....

First of all, congrats on your project!
Glad to see more folks out there willing to do conversions etc to get more
db on six.

>From what you've said, and by the choice of your plate tuning cap, you 
>still
have too much minimum C.
A 100pf variable is likely to have a minimum C of around 10-15pf, which is
just too much.
If you have a means to check the cap, do so, and I'll wager that you'll find
your lowest reading (installed in the amp) is simply too much.

There are a number of physically smaller caps available that are made by the
same mfger of your caps now that would be a much better choice.
For example, the Cardwell 154-11-1 is a good choice. It has a max C of about
45pf.
Remember, your tubes contribute 10-12pf each to the plate C.
I would think that your plate tune C, at resonance, will be only 7-10pf
assuming a loaded Q of 12 or so.

The Cardwell unit can be made to go lower on minimum C by removing a couple
of rotor plates.
I have used this cap in numerous six meter amps with excellent results.
These caps sell at Dayton for $20 on average.

My suggestion is to get the plate tank resonant first and then fiddle with
the parasitic chokes.
You may well find that what you have presently is fine once you get your
tank resonant and the efficiency up.
You haven't mentioned any changes to the filament choke; have you removed
some of the turns on this choke?
Also, have you changed the plate RFC?

I'm sure Carl and some others who do these conversions for a living will
chime in after a bit, so you will get some more help on this.

I've got a number of those Cardwell caps should you decide to pursue a
physically smaller and electrically smaller plate tune cap.

Good luck,
Dick, K5AND
Austin, TX


> -----Original Message-----
> From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]
> On Behalf Of Gary Myers
> Sent: Friday, January 21, 2011 10:14 PM
> To: Amps
> Subject: Re: [Amps] Help with HL2200 6 meter conversion
>
> Hello....
>
> I've just completed converting a Heathkit HL2200 amp, stripping all the
tank out as
> well as the input ckt. I left the existing plate tuning cap in and am
using it as the
> load cap. The plate tuning cap, now where the load cap was, is a 100pf
variable.
> This was all down according to an April '08 article on the same. The input
is a T
> network and it by the way works perfectly with a 1:1 SWR.
>
> The suppressors are as the article says - nichrome ribbon, 1/4" wide
formed into a
> U with 3 2W carbon resistors in parallel at its base. All soldered using
silver solder
> for the nichrome. All seemed to go fine.
>
> After installing the tank components I used a dip meter to try and see if
the tank
> coil was set right. I first confirmed the meter setting by checking it on
a radio set to
> 50.1Mhz... and then tried to insert its coil into the limited area of the
tank coil... it
> measured 60Mhz! So I squeezed the turns together - it dropped to 54Mhz...
I
> decided to leave it as is and wait until I could power it up.
>
> When I first tried to run it I was only able to get about 60W out with
about 20W
> drive and the plate tune cap was at its minimum setting... I believe this
indicates
> that indeed the coil is too much inductance (does it not?) and so I pulled
the turns
> apart as best I could. This allowed me to get about 350W out (with about
840W in)
> with maybe 35W drive (I didn't measure this by itself - just going by
where I had the
> power set on the 746Pro). But very quickly, before I could increase the
input, it
> started to smell! The carbon resistors were getting VERY hot.
>
> I quickly removed the cover (obviously made sure the HV was 0) and with a
thermal
> gun checked the temperature of the suppression resistors - one set was at
about
> 160 deg and the other set about 125 degrees. One resistor in the one set
appears
> to be higher than the others - but this might just be the difficulty in
checking with a
> thermal gun.
>
> So my question is: WHY are these getting hot?! I would have thought, if
the article
> said use these resistors, that it would work fine. The U nichrome wire is
almost
> identical to the one they have pictured (mechanical picture for scale) in
the article.
> Note I couldn't find the 150 ohm resistors they said - I used 3 180 ohm
resistors -
> but I find it impossible to believe that it would work with 50 ohms eqv
and not 60
> ohms eqv nor that the 60 ohm eqv should dissipate MORE power, not less.
>
> I'm also a bit troubled by the efficiency... but until I get this resolved
I'm not going
> to worry too much about this - however if someone things it is related I'd
love to
> hear it.
>
> Thanks for your time.
>
> Gary
> K9RX
>
> [the amp was bought from someone that said it had been converted to 6
meters
> replacing the 10 position and the other bands still there... it didn't
work on 6 which
> didn't make me happy so I decided to rip it all out and just make it a 6
only amp...
> note however it would put out about 1150W on 20 meters before the change.]
>
> ps: Also note that when I remove the cover (the HV short is disabled) I
get 550W
> out with about 800W in but now the load cap is at its maximum value!
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps



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

Message: 4
Date: Sat, 22 Jan 2011 10:25:35 +0000
From: Mike Tubby <mike@tubby.org>
Subject: Re: [Amps] Fireing up a old Tl922 amplifier.
To: BEHIELS JEAN-PIERRE <ON4AEF@base.be>
Cc: amps@contesting.com, TexasRF@aol.com
Message-ID: <4D3AB09F.5070805@tubby.org>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed


It might be worth powering up the amp with the tubes out just in case
you have a problem with a tube.

I had one tube that was very low emission but was able to re-activate it
using the circuit described here:

http://www.xs4all.nl/~pa0fri/Lineairs/TL922/tl-922eng.htm
<http://www.xs4all.nl/%7Epa0fri/Lineairs/TL922/tl-922eng.htm>

there's also a lot of good engineering tips on PAR0FRI's pages.

So far I've put the HT glitch resistor and fuse in and changed the
suppressors.

My amp is happiest on 40m (no surprise there really) and will provide
approx 1150W out, dropping to about 950W on 10m.


Mike G8TIC




On 21/01/2011 14:28, BEHIELS JEAN-PIERRE wrote:
> Thanks for the good technical explanation.
> I really don't need this accurate measure around this 47ohm/50W 
> resistor,but I have done due the fact I saw he has coming up very hot !
> Maby I measured in DC position or not,I could not confirm(maby I measure 
> wrong,but there flows more than a few hunderd mA !!! )
> I can suppose my environmental measurement was quit a signal for my that 
> there must flow a lot of current without any charge.
> Due the hot temperature around the 47ohm resistor and the big current I 
> saw,I was curieus if this is normal value with no charge for the high 
> tension supply of this TL922 unit ?
> The capicitors and there bleeders resistances are very difficult to reach 
> inside the cabinet for a DC voltage measurement !!
> To be honest I never saw sutch high no-charge currents for a amplifier 
> unit,what wouldit be with charge more than presumed I think (Ic for a 
> TL922 = max 650mA)?
> I will do a effort next days to reach the capacitors and there bleeders to 
> do a DC measuring again.
> I must say nothing has been blowed-up after about 8 hours of no charge 
> service,thats the reason I am not really scared around,but I must say it 
> is mutch has a idle currrent value I found ??
>
> 73's
> Jean ON4AEF.
>
>    ----- Original Message -----
>    From: TexasRF@aol.com
>    To: ON4AEF@base.be ; amps@contesting.com
>    Sent: Friday, January 21, 2011 2:30 PM
>    Subject: Re: [Amps] Fireing up a old Tl922 amplifier.
>
>
>    Hi Jean, there several ways to measure the 1A current flow. One method 
> is to measure voltage drop across the 47 ohm resistor. If you are doing 
> that with a typical digital voltmeter it will display a value that is 
> approximately .707 times the peak voltage. Since the filter capacitors are 
> charging only on ac peaks, you are not delivering power to a totally 
> resistive load. As a result, the waveform across the resistor will not be 
> a sine wave and the voltage reading will be much higher than the rms 
> value.
>
>    An accurate current reading will require use of an average reading 
> ampere meter such as iron vane type. For your purposes an accurate reading 
> is not needed.
>
>    If you are measuring voltage drop across the 47 ohm meter and seeing 47 
> vac, then your reading is very similar to some I have taken with a 35 ohm 
> resistor in the primary of a hv power supply. In my case, I was using the 
> resistor to reduce the standby dc voltage to equal the full load voltage.
>
>    If you can measure the dc voltage across each filter capacitor it will 
> give a good indication how they are forming. If one is much lower than 
> others it indicates leakage and perhaps needs more time to form or is 
> defective. It could also indicate the bleeder resistor has changed value 
> and needs replacement. If a capacitor reads much higher than others it 
> indicates the bleeder resistor is defective and needs replacement.
>
>    73,
>    Gerald K5GW
>
>
>
>
>    In a message dated 1/21/2011 1:58:05 A.M. Central Standard Time, 
> ON4AEF@base.be writes:
>
>      Hi;
>
>      Best wishes for you all for 2011.
>
>      I am quit making my own start delay into a old (1988)TL922 amp.
>      I made two primary transformer start up delays  for : A for filament 
> supply.
>                                                            B for HV 
> sequencial
>      start-up supply.
>
>      A little explanation about my substantial modifications concerning 
> the
>      TL922 power supplys.
>      By powering-on I switch all ready a resistance of 10 ohm/50W into the
>      primary of the filament transformer circuit.
>      After about 3 minutes I switch on the HV tension with in series a 
> resistance
>      of 47ohm/50W by means of timer T1
>      I mean time I also swich-out the 10 ohm/50 W of the primary of the 
> filament
>      transformer by means of that same timer T1'
>      After 5 minutes I switch-out the 47 ohm/50W resistor of the primary 
> of the
>      HV-supply transformer by means of timer T2.
>
>      This principle works quit very well and it is very safely for the 
> start-up
>      life time of the 3-500Z tubes ?
>      But I was a little bit scary about the cuurent (1A over 47 ohms is 
> 47W
>      !!!)witch flows of the HV-supply
>      without charge during the 47 ohm/50W resistance was in circuit..
>      Just some bleeders resistances over the HV-supply C's and over the 
> whole
>      supply as stabilisation of the power HV-supply output.
>      I could not believe it was about 1A ???
>      That was quit a good reason to ask some question around ?
>      Today I leave the whole AMP under supply for a whole day nothing 
> happens
>      around.
>      May I conclude everything is normal behind my old Tl922 ?
>
>      So a big story but I like to now some others guys opinion and 
> experiences
>      around this remarquable
>      consumption of the HV-supply and measurement I made around a TL 922.
>
>      73's Jean ON4AEF.
>
>
>
>
>
>      >  ----- Original Message -----
>      From: "Jim W7RY"<w7ry@inbox.com>
>      >  To: "BEHIELS JEAN-PIERRE"<ON4AEF@base.be>;<amps@contesting.com>
>      >>  Sent: Wednesday, January 19, 2011 4:20 PM
>      >>  Subject: Re: [Amps] Fireing up a old Tl922 amplifier.
>      >>
>      >>
>      >>>  How long is your delay? Should be no more than .5 second to 1 
> second.
>      >>>
>      >>>  73
>      >>>  Jim W7RY
>      >>>
>      >>>
>      >>>  --------------------------------------------------
>      >>>  From: "BEHIELS JEAN-PIERRE"<ON4AEF@base.be>
>      >>>  Sent: Wednesday, January 19, 2011 12:18 AM
>      >>>  To:<amps@contesting.com>
>      >>>  Subject: [Amps] Fireing up a old Tl922 amplifier.
>      >>>
>      >>>>  Hi,
>      >>>>
>      >>>>  I am busy to fireing up a old Kenwood TL922 amplifier(1985).
>      >>>>  I have already build in a start-up system for both filament and 
> high
>      >>>>  tension power supplys by means of two homebrew timers,and a 
> series
>      >>>>  small
>      >>>>  resistances in
>      >>>>  de secundairys of both transformers(filament 10 ohm-HV 47 ohm 
> both
>      >>>>  50W).
>      >>>>  Both valves are not mounted(running with no charges no 
> consume).
>      >>>>  By power-on the unit I saw that the resistance of 47ohm/50W 
> into the HV
>      >>>>  supply is becoming very hot.
>      >>>>  I have made some measurements during start up around this 
> resistance
>      >>>>  and
>      >>>>  measure 47 V over this resistance.
>      >>>>  This means that the HV power supply without charge consume 1A 
> idling
>      >>>>  current !!!
>      >>>>  Question is this normal ?
>      >>>>  After the timing sequence the resistance is normally pulling 
> out of the
>      >>>>  system and the supply runs like it must be I suppose,nothing 
> abnormal
>      >>>>  happens further !!
>      >>>>  No overheating behind the amplifier box or whatever,no smoke or 
> burning
>      >>>>  and heating components.
>      >>>>  Just the 10W bleeders over the capacitors warm up a little (can 
> easely
>      >>>>  take my hand on it hi )
>      >>>>  I was wondering while this is so mutch or not ?
>      >>>>  Did I leave the amp a lot many hours under supplying condition 
> to the
>      >>>>  give the HV-capacitors the time to reforme after sutch long 
> time(if
>      >>>>  this
>      >>>>  is the reason) ???
>      >>>>  Could this last also a reason of the fenomene ?
>      >>>>  Or is 1A just normal standby current value for this amp .....
>      >>>>
>      >>>>  Regards Jean ON4AEF.
>      >>>>
>      >>>>  _______________________________________________
>      >>>>  Amps mailing list
>      >>>>  Amps@contesting.com
>      >>>>  http://lists.contesting.com/mailman/listinfo/amps
>      >>>>
>      >>>>
>      >>>>
>      >>>>  -----
>      >>>>  No virus found in this message.
>      >>>>  Checked by AVG - www.avg.com
>      >>>>  Version: 10.0.1191 / Virus Database: 1435/3389 - Release Date: 
> 01/18/11
>      >>>>
>      >>
>      >
>
>      _______________________________________________
>      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



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

Message: 5
Date: Sat, 22 Jan 2011 03:21:07 -0800
From: Vic K2VCO <vic@rakefet.com>
Subject: Re: [Amps] Help with HL2200 6 meter conversion
To: amps@contesting.com
Message-ID: <4D3ABDA3.3020104@rakefet.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

First of all, you can't trust the dip meter because the frequency will 
change when you
couple it to the tank circuit. When I use one I wrap a turn or two of wire 
around it and
connect it to a frequency counter. Then when I get a dip I look at the 
counter.

The best way to adjust a tank circuit is to compute the plate load 
impedance, and then
temporarily place a non-inductive resistor of that value from plate to 
ground (power OFF,
of course!). Then connect an antenna analyzer to the output and adjust for a 
1:1 SWR. That
way you are establishing that the tank can transform the load impedance to 
50 ohms.

You will need also to estimate or measure either the inductance or capacity 
in the
circuit, including strays, to make sure the Q is in the ballpark. I use a 
AADE LC meter to
do this, but you have to isolate the component (L or C) that you are 
measuring from the
rest of the network.

If the parasitic suppressors are getting hot, then perhaps the inductance of 
the U is too
high, but also I'm guessing that if the network is not set up properly the 
RF current
could be higher than expected.

I don't think there's an advantage from making the U out of Nichrome.


On 1/21/2011 8:13 PM, Gary Myers wrote:
> Hello....
>
> I've just completed converting a Heathkit HL2200 amp, stripping all the 
> tank out as
> well as the input ckt. I left the existing plate tuning cap in and am 
> using it as the
> load cap. The plate tuning cap, now where the load cap was, is a 100pf 
> variable. This
> was all down according to an April '08 article on the same. The input is a 
> T network
> and it by the way works perfectly with a 1:1 SWR.
>
> The suppressors are as the article says - nichrome ribbon, 1/4" wide 
> formed into a U
> with 3 2W carbon resistors in parallel at its base. All soldered using 
> silver solder
> for the nichrome. All seemed to go fine.
>
> After installing the tank components I used a dip meter to try and see if 
> the tank coil
> was set right. I first confirmed the meter setting by checking it on a 
> radio set to
> 50.1Mhz... and then tried to insert its coil into the limited area of the 
> tank coil...
> it measured 60Mhz! So I squeezed the turns together - it dropped to 
> 54Mhz... I decided
> to leave it as is and wait until I could power it up.
>
> When I first tried to run it I was only able to get about 60W out with 
> about 20W drive
> and the plate tune cap was at its minimum setting... I believe this 
> indicates that
> indeed the coil is too much inductance (does it not?) and so I pulled the 
> turns apart
> as best I could. This allowed me to get about 350W out (with about 840W 
> in) with maybe
> 35W drive (I didn't measure this by itself - just going by where I had the 
> power set on
> the 746Pro). But very quickly, before I could increase the input, it 
> started to smell!
> The carbon resistors were getting VERY hot.
>
> I quickly removed the cover (obviously made sure the HV was 0) and with a 
> thermal gun
> checked the temperature of the suppression resistors - one set was at 
> about 160 deg and
> the other set about 125 degrees. One resistor in the one set appears to be 
> higher than
> the others - but this might just be the difficulty in checking with a 
> thermal gun.
>
> So my question is: WHY are these getting hot?! I would have thought, if 
> the article
> said use these resistors, that it would work fine. The U nichrome wire is 
> almost
> identical to the one they have pictured (mechanical picture for scale) in 
> the article.
> Note I couldn't find the 150 ohm resistors they said - I used 3 180 ohm 
> resistors - but
> I find it impossible to believe that it would work with 50 ohms eqv and 
> not 60 ohms eqv
> nor that the 60 ohm eqv should dissipate MORE power, not less.
>
> I'm also a bit troubled by the efficiency... but until I get this resolved 
> I'm not
> going to worry too much about this - however if someone things it is 
> related I'd love
> to hear it.
>
> Thanks for your time.
>
> Gary K9RX
>
> [the amp was bought from someone that said it had been converted to 6 
> meters replacing
> the 10 position and the other bands still there... it didn't work on 6 
> which didn't
> make me happy so I decided to rip it all out and just make it a 6 only 
> amp... note
> however it would put out about 1150W on 20 meters before the change.]
>
> ps: Also note that when I remove the cover (the HV short is disabled) I 
> get 550W out
> with about 800W in but now the load cap is at its maximum value!
>
> _______________________________________________ Amps mailing list 
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps

-- 
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco/


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