[Amps] filament transformers

[Jim W7RY]

BTW you can see my amplifier here:

http://home.centurytel.net/w7ry/Jims%20Amplifier%20Page.htm


73
Jim W7RY

----- Original Message ----- 
From: "Jim W7RY" <w7ry at arrl.net>
To: <amps at contesting.com>
Sent: Saturday, May 16, 2009 7:50 AM
Subject: Re: [Amps] filament transformers


> My homebrew 3CX800 amplifier filament transformer started with a 3 amp 12
> volt Radio Shack transformer. I did not have enough voltage so I simply
> added a few turns and increased the voltage for the two tubes.
>
> The transformer had lots of extra space on the windings and I did not even
> have to remove the laminations. I simply carefully scramble wound about 10
> more turns of #18 (could have been #20) enameled wire. Kept measuring the
> voltage until I had what I needed.
>
> The original windings were scramble wound too so no need for neatness with
> my added windings.
> 73
> Jim W7RY
>
>
>
> ----- Original Message ----- 
> From: "robert briggs" <vk3zl at bigpond.com>
> To: <amps at contesting.com>
> Sent: Saturday, May 16, 2009 6:03 AM
> Subject: [Amps] filament transformers
>
>
>> You are right Carl...I have always had the roving eye at hamfests and
>> disposal stores..I once brought 5 new Jennings  vac variables, 5-500pf
>> for one dollar each at a disposals place...When I took them to the
>> counter and asked how much, the guy said $5 for the glass tubes....I
>> nearly ran all the way home...
>>
>> It is a shame that a lot of the old arts of home brew are being lost
>> these days..I know that many think that they don't have the ability but
>> the fact for me has been necessity as many components are just not
>> available in VK and too expensive to import..I still have a shed full of
>> "treasures" which I have collected over the years and I regularly search
>> through forgotten boxes of heaven knows what and old chassis looking for
>> "that" part" to complete a project..
>> I remember my first 80 meter transmitter crystal controlled...I pulled
>> apart many old FT43 crystals and re ground them on a piece of glass with
>> some bath cleaner, a painstaking job that many hams much older than me
>> will remember well..That was about the time I started re winding old
>> transformers and have been doing it since...You have to be inventive
>> some of the time but I guess that is what gives us the satisfaction when
>> you put something together and bring it to life...
>>
>> Ah well, I guess time moves on and things change....
>>
>> 73 all..Bob VK3ZL..
>> _______________________________________________
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>> Amps at contesting.com
>> http://lists.contesting.com/mailman/listinfo/amps
>>
>
>
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