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Original Message
RE: how to remove feedback loops
Posted by rage on June 11, 2017 at 15:04:02:
each of the output tubes need their screen tied to the plate through a 100 ohm resistor. currently the screens are tied directly to b+. this will triode strap the output stage and reduce the need for feedback.
next remove the global feedback loop from the secondary of the output transformer to the cathode of the driver tube. you should also remove the switch and combine the 3 resistors into one. you may want to bypass that resistor with a capacitor also - or try it both ways. without a capacitor on the cathode you will introduce degenerative feedback and reduce gain. good luck!