Sounds like a 10uF would probably work with a 274B and 5U4. I may be being sent some Mundorf 3.9uF for free, it seems like these would work well for the 274B... would it also work for the 5U4?
Sure, if they're rated for 600+ vdc. Check your B+ afterward, though, it may be lower than you want. And you may get an increase in ripple noise.
Thanks Grover.. The 5R4G is close in ratings and might be a good substitute too for the PSU I linked. Peckjed’s circuit looks like it could work with the 5R4G(Y) too if input cap is reduced to 10uF..
I know this was from a while ago. I installed the 10uF cap in place of the 30uF and the diodes on the rectifier. No issues with the rectifier anymore! However, I am noticing a hum from the choke that’s seems to be transferring to a 60hz hum on the speakers. Could lowering the 30uF to 10uF have caused this?
No. That hum (if any) would be 120Hz. Are you sure it's not 120Hz?
60Hz usually is caused by ground loops/heater hum. If you short the inputs to ground, does the hum go away? If yes, it's a ground loop.
Does the hum go away as soon as you switch the amp off? If yes, this means it's coming from the power supply of the amp, either electrically, or magnetically.
60Hz usually is caused by ground loops/heater hum. If you short the inputs to ground, does the hum go away? If yes, it's a ground loop.
Does the hum go away as soon as you switch the amp off? If yes, this means it's coming from the power supply of the amp, either electrically, or magnetically.
There is a small amount of 120hz hum, but also lower frequency 60hz. (If my understanding is correct 120hz is higher pitched, almost a buzz and 60hz is lower pitched hum).
I’ll test if the hum goes away when shorting the input.
Yes, the hum goes away as soon as I power the amplifier off.
This is the power simply schematic: Legend power supply - Album on Imgur
Dumb question - can a choke be wired backwards?
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