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Old 7th December 2007, 12:30 AM   #1
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Default Problem: attenuation after cathodyne and CF

I built the circuit attached but I'm having four times less voltage than the input at the output of the phase splitter and the CF.
The measured DC voltages are OK and I swapped the tubes and the problem persist, so I believe the problem is the circuit.

The +B is 140V.

Thanks for any help.
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Old 7th December 2007, 01:05 AM   #2
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There are a pile of problems with that circuit. The distortion will be much worse than it needs to be. Same with balance.

As for the gain, I calculate about 0.9, so you probably have a wiring or measurement error. Are you measuring the gain just to one side or is that differential gain?
A philosopher is a blind man in a dark room looking for a black cat that isn't there. A theologian is the man who finds it. - Mencken
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Old 7th December 2007, 07:05 AM   #3
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140V B+ is too low. I'd increase it to at least 240V.
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