02-14-2017, 10:38 AM
Does your radio have a 100 ohm resistor (R5) in series with the tube filaments? It looks like it connects between the filament pins of the two 7B7 tubes.
This resistor drops the filament voltage by 15 volts, which is the same amount that would be needed for a 50L6 compared to a 35L6. If there is no R5 series resistor, the circuit requires a 50L6.
This resistor drops the filament voltage by 15 volts, which is the same amount that would be needed for a 50L6 compared to a 35L6. If there is no R5 series resistor, the circuit requires a 50L6.