06-08-2022, 04:30 PM
Hi J,
Welcome to the Phorum.
Your tube substitution should be fine for now. If you are looking for best performance you can replace it later.
Schematic:
http://www.nostalgiaair.org/resources/233/M0013233.htm
When you say the voltages test OK, does that mean you tested all the tube sockets or only B+? Testing the audio section, do you get a low level hum when the volume is turned up? How about when you touch the grid cap of the 6Q7? If you get no response from either of these then there's something wacky in the audio amplifiers. Double check all the components, even the ones you didn't change, someone else might have made a mistake just to throw you off.
Welcome to the Phorum.
Your tube substitution should be fine for now. If you are looking for best performance you can replace it later.
Schematic:
http://www.nostalgiaair.org/resources/233/M0013233.htm
When you say the voltages test OK, does that mean you tested all the tube sockets or only B+? Testing the audio section, do you get a low level hum when the volume is turned up? How about when you touch the grid cap of the 6Q7? If you get no response from either of these then there's something wacky in the audio amplifiers. Double check all the components, even the ones you didn't change, someone else might have made a mistake just to throw you off.
