Those two diets you were talking about are not normal diodes they are transient voltage suppressors. They won’t conduct until the voltage gets around 10 V.
Be very careful with that PA bias. You can easily destroy the transistors with that. ?Turning it too far will cause the bias current to go to many amps!!
There is some odd residue near the input of your output transformer. ?
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On Feb 28, 2025, at 19:39, Gordon Gibby KX4Z via groups.io <docvacuumtubes@...> wrote:
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be certain that you have correctly identified the PA bias potentiometer. It would be very odd if turning that too far didn’t destroy the MOSFETs
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when you press push to talk the voltage on L 80 and L 81 should go up— because it is controlled by Q9. if Q9 is continuously on, then you have blown a different MOSFET, one or more in that complicated switching system around Q9. ?You might want to figure out for sure if you really can’t see switching action going on there.
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