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Update.  I have dc voltages on the filter caps that look ok, at 376,338,and 241 big to small. DC

On a 6V6 there’s 373vdc at pin 3, and 340vdc on pin 4 with 122 vac from my variac  so that’s all high, but there’s hum to the speaker now, that doesn’t change with volume or tone, and  scratching sounds from the speaker when the tube pins are probed.  I’ve input guitars and sine wave signals, but none of that comes out.

At the 100k resistors from the 12ax7, I get 150 and 153 vdc.  Feels like a win

thats the good news.

My filament situation is Fugese.  The yellow wires that should supply the 5v ac to the rectifier are showing 380vdc!  The red pair at 330vac.

At the lamps, one green wire shows 6.5vac, and the tube pins on that wire show 6.5vac. The other wire has no voltage, and so the corresponding tube pins don’t either. The tubes do in fact look half- bright.

unsure if it was doa or if my mistakes cooked the pt, but it seems to be malfunctioning.  I’ll look up ways to test them, and any ideas and suggestions from y’all will be appreciated.

This amp will run!


thanks. Doug