Does anyone recognize this wave form? This is with no input signal.
First pic is the plate of V1 (pin 6).
I swapped R7 with a volume pot where lug 1 is circuit common, lug 2 is V2grid and lug 3 is V1 coupling cap. Grounded to v1 filter cap negative.
Turning the volume control UP reduces the amplitude of the buzz.
Second pic is the plate of V1A (Pin 1/Pin8). Volume control does not affect this.
Input grid from the Input transformer is quiet, but connecting a microphone knocks down the buzz on the plates a little.
I did not connect the NFB from the OT Secondary, but DID connect R11/C9.
Brand new filter caps, swapped multiple V1 tubes.
First pic is the plate of V1 (pin 6).
I swapped R7 with a volume pot where lug 1 is circuit common, lug 2 is V2grid and lug 3 is V1 coupling cap. Grounded to v1 filter cap negative.
Turning the volume control UP reduces the amplitude of the buzz.
Second pic is the plate of V1A (Pin 1/Pin8). Volume control does not affect this.
Input grid from the Input transformer is quiet, but connecting a microphone knocks down the buzz on the plates a little.
I did not connect the NFB from the OT Secondary, but DID connect R11/C9.
Brand new filter caps, swapped multiple V1 tubes.
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