and thinking longer about it, the 25v cap is attached to both channels, so it really should not be an issue with that cap. I did not attach that cap as famousmockingbird suggested though. I used the original lead (yellow wire sticking up on the right hand side of the pic) and attached the negative lead to the ground on the input. could that be causing an issue? the resistor on the other end of that circuit is grounded to the tube socket. just spitballing here.
OK. I undid everything I did the previous night and made things much neater. I now have sound out of both channels. The left channel is pretty quiet, much improved hum level. The right channel still has about the same amount of hum though. That side of the amp also has the rectifier tube, so I probably have some lead wires running too close to each other. I will attempt to tidy thing up a bit more to see if I can resolve that. Any additional words of advice for rewiring the heaters?
Stereo Stroke
Thanks for the thread brandoh73 . I am currently working on the exact same amp and your post of the schematic has shed some light on those pesky copulates. The amp I'm repairing acts like it has suffered a stroke. One channel works fine, but the other crackles on warm-up with music playing for about 3 seconds and then totally dies. It's not the 6bq5 or the 6eu7, all work fine. I replaced the filter cap section and one fried resistor (1k5 after the 40mf,) but the problem persists. I suspect dc leak in the coupling caps. I'm about to replace the .1 caps with some orange drops and then use the texas shotgun approach and rebuild the copulates with some perfboard. Any advice or speculation from the experts would be happily recieved.
Thanks for the thread brandoh73 . I am currently working on the exact same amp and your post of the schematic has shed some light on those pesky copulates. The amp I'm repairing acts like it has suffered a stroke. One channel works fine, but the other crackles on warm-up with music playing for about 3 seconds and then totally dies. It's not the 6bq5 or the 6eu7, all work fine. I replaced the filter cap section and one fried resistor (1k5 after the 40mf,) but the problem persists. I suspect dc leak in the coupling caps. I'm about to replace the .1 caps with some orange drops and then use the texas shotgun approach and rebuild the copulates with some perfboard. Any advice or speculation from the experts would be happily recieved.
It turns out the right side OT was fried. Not sure if the dying filter caps took the tranny out, or if an unplugged speaker took the tranny and caps. Either way the stereo is now a mono. It looks like a Hammond OT set is going to run around $100. Unless anyone out there has a lead on a suitable replacement, I think this might become a guitar amp.
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