12-29-2012, 04:40 PM
OK, I put in 5W resistors, and the buzz/hum/growl is still there, though with a slightly different sound. It gets much louder when switched to phono.
I took out the audio amp 41 tubes, turned on power and the speaker hums, much louder than a speaker with no audio amplifier feeding into it should. I'm pretty sure the field coil, a part of the filter circuit, shouldn't be this noisy. This all leads me to believe that either the 5Y4G rectifier is weak or the (supposedly) new electrolytic filter caps are leaky. I'm leaning toward the tube because this is a used one I pulled out of my 39-45, which had recently developed a good bit of 60 cycle hum.
Sheesh, I need to invest in a decent tube tester.
I guess I'll just pack this thing up and take it back home with me this weekend. I have a new rectifier tube waiting on me there, anyway.
Of course, feel free to speak up if any of you think I'm wrong. I'm all ears on this thing.
I took out the audio amp 41 tubes, turned on power and the speaker hums, much louder than a speaker with no audio amplifier feeding into it should. I'm pretty sure the field coil, a part of the filter circuit, shouldn't be this noisy. This all leads me to believe that either the 5Y4G rectifier is weak or the (supposedly) new electrolytic filter caps are leaky. I'm leaning toward the tube because this is a used one I pulled out of my 39-45, which had recently developed a good bit of 60 cycle hum.
Sheesh, I need to invest in a decent tube tester.
I guess I'll just pack this thing up and take it back home with me this weekend. I have a new rectifier tube waiting on me there, anyway.
Of course, feel free to speak up if any of you think I'm wrong. I'm all ears on this thing.