>
>measures wrote:
>>
>> >
>> >I just noticed that the filament transformer I was planning to use (got it
>> >free)
>> >for my 2 x 3-500z amp does not have a center tap. It has two 5v 20a
>windings
>> >which I was going to put in parallel.
>> >
>> Put the windings in series and you have a CT.
>
>But then the "CT" is unbalanced with respect to each tube, since the
>filaments
>have to be in series too. How is this different from putting them in
>parallel
>and connecting the b- return to one side?
>
It is different because you can't hear hum modulation on the air. The
TL-922 uses a 10 or so volt source with the 3-500Z filaments in series.
The operator at the receiving end hears no hum modulation.
- Rich..., 805.386.3734, www.vcnet.com/measures.
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