[Amps] Source for plate xfrmer

[Steve Bookout]

Guys,

This is where I think i got into trouble.  

I rebuilt a BTI 2000 that had already had another PS put in place of the original. The resultant load impedance was so far from the original design that efficiency was REALLY low.  
I built a new supply with a transformer I had used in another amp.
I used GM3SEK's on-line calculator to rebuild the RF deck into a fixed, 80 meter only amp.  (This was for the 80 m position at my M/M.) 
Really beefed things up and was well satisfied with how the RF deck worked out.
PS, not so much.  Abt 4500 volts no load and abt 3600 at 500 mils.  
Now, the real working voltage is much less than I designed the RF deck for.  Efficiency is off, although not nearly as bad as when i started.
A year and a half ago, I put it on the air for CQWW CW.  1300 watts during a tune up, equals abt 1600, or more when sending CW.  Dynamic regulation stinks!  You have to tune, then send CW to see where the power is.  Adjust and repeat.
I remember saying to myself 'Blow up you &%¥€#?@, then I'll get you right!'.  It stayed on 3502.3 KHz all weekend, for abt 1200 80 mtr Q's.  
If that had been because of resistance in the caps, they would have quickly died from the heat. BTW, they are low ESR, 105 C caps.
Anyway, it is rugged, although it is far from perfect.  I'm a bit like the TV character 'Monk', and this is just bothering the Hell out of me.
Both my 160 m, 4-1000 amp and my 40 m, 8877 amp have power supplies that use Dahl transformers at 4200 v rated at 1.5 A CCS.  They hardly flicker.

I know I checked the secondary resistance.  I knew better, but it just didn't sink in, I guess.  Don't remember what it was now.

Anyway, this is where I am and how I got here.

73 de Steve, NR4M

Sent from my iPad

On Feb 13, 2012, at 22:13, "Carl" <km1h at jeremy.mv.com> wrote:

> Are those suitable for ham amp use or do they have old style high impedance (and DC resistance) windings that are not that suitable for a big C only filter?
> IE: Pole Pigs
> 
> Carl
> KM1H
> 
> 
> 
>  ----- Original Message ----- 
>  From: B Osburn 
>  To: Al Kozakiewicz ; Steve Bookout ; amps at contesting.com ; Carl 
>  Sent: Monday, February 13, 2012 9:52 PM
>  Subject: Re: [Amps] Source for plate xfrmer
> 
> 
>  I don't think this is what you are looking for but Monster Controls has used control power XFMRs.  I paid $950 for a 5kVA 240/2400V + Shipping. They only come in common medium voltage (MV) switchgear voltages 2400, 4160, 6900V.  Sizes range from 0.75kVA to 5kVA. 
>  Brad AB0YD
> 
>  http://www.monster4controls.com/parts/cat/control%20power%20transformer/
> 
> 
>    ----- Original Message ----- 
>    From: Carl 
>    To: Al Kozakiewicz ; Steve Bookout ; amps at contesting.com 
>    Sent: Monday, February 13, 2012 4:55 PM
>    Subject: Re: [Amps] Source for plate xfrmer
> 
> 
>    And you pay thru the nose. Id check with Heyboer Transformer if you Dont 
>    have to have a C-Core.
> 
>    Carl
>    KM1H
> 
> 
>    ----- Original Message ----- 
>    From: "Al Kozakiewicz" <akozak at hourglass.com>
>    To: "Steve Bookout" <steve at dx4win.com>; <amps at contesting.com>
>    Sent: Monday, February 13, 2012 1:38 PM
>    Subject: Re: [Amps] Source for plate xfrmer
> 
> 
>> Unless something changed, Harbach Electronics now makes/sells the Dahl 
>> transformers.
>> 
>> Al
>> AB2ZY
>> 
>> ________________________________________
>> From: amps-bounces at contesting.com [amps-bounces at contesting.com] On Behalf 
>> Of Steve Bookout [steve at dx4win.com]
>> Sent: Monday, February 13, 2012 1:35 PM
>> To: amps at contesting.com
>> Subject: [Amps] Source for plate xfrmer
>> 
>> Hello all,
>> 
>> Where do you look for a new HV plate transformer these days?
>> 
>> I understand Peter Dahl is no longer around.
>> 
>> I'm looking for 3000 VAC secondary @ 1+ amp CCS.
>> 
>> TIA
>> 
>> 73 de Steve, NR4M
>> 
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