04-08-2014, 05:11 PM
You can go higher with the resistor. I would try a 10K first and if the hum is still excessive go to 22K.
Check the voltage on the cathode of the AVC tube and see if it varies as you turn the volume control. The volume control pot is fed bias voltage from the power supply through another similar choke L 17 with a resistance of 2300 ohms, so perhaps it is open too?
Check the voltage on the cathode of the AVC tube and see if it varies as you turn the volume control. The volume control pot is fed bias voltage from the power supply through another similar choke L 17 with a resistance of 2300 ohms, so perhaps it is open too?
