Hi,
I'm going to re-tube a tube amp that I have, barely readable schematic attached. I've figured out what I need to do to set the bias current.
What I haven't figured out is how to adjust the second trim pot that I designated TR2, I think it reads 250R. Somewhere in a youtube comment someone claimed that it's a hum balance pot that balances the heaters. To me it doesn't look like it balances anything, instead it lets you put more or less load on the heaters. How do you set it correctly? Simply listen to the hum and make it as low as possible? How / why does the heater load influence the hum?
Thanks,
hrs
I'm going to re-tube a tube amp that I have, barely readable schematic attached. I've figured out what I need to do to set the bias current.
What I haven't figured out is how to adjust the second trim pot that I designated TR2, I think it reads 250R. Somewhere in a youtube comment someone claimed that it's a hum balance pot that balances the heaters. To me it doesn't look like it balances anything, instead it lets you put more or less load on the heaters. How do you set it correctly? Simply listen to the hum and make it as low as possible? How / why does the heater load influence the hum?
Thanks,
hrs
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