04-07-2025, 05:56 PM
I don't know what you are referring to when you say "tube cathode ground". Ground is a connection to the chassis or B-. The cathode of the 6A7 is grounded and so are the two resistors. They could be attached to ground anywhere in the chassis, they don't have to be at the same terminus as shown in the schematic. So I can't understand why this is an issue.