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RE: Do your voltages somewhat match the schematic? (nt)

Posted by vinnie2 on June 22, 2017 at 08:03:58:
Did like you suggested. PSU is ok, nice and steady by itself. Then I installed just the driver 12at7 tube and it's voltages are pretty much in the ballpark. I then plugged in the 6bq5's. I was getting around the 13 volts at the cathode resistor with the 400 ohm resistor in place that the schem calls for, for about 33 mA for cathode current if I am doing the calcs right. The tube manual says it should be about 65 mA, but would that be for a shared cathode resistor too? Still distorting a lot. The other voltages are in the ballpark too. I am at a loss as to what to try next. Maybe I should test some 6bq5's and !2at7's and make sure I have a good set of tubes? Maybe hook a test signal to it and follow it through on a scope and see if I can see where it starts distorting?