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I was gifted a Mesa F30 and it was in pieces when I got it. I put it all back together and it's working fine after a lot of TLC, but I want to lower the bias; it's running at 100% and gets really hot. Years ago I had a DC3 that I sold for the same reason.
I studied the schematic and was going to change the voltage divider for the bias circuit but then realized that this funky phase inverter circuit that Mesa uses is on the same leg, so any change is going to throw the PI cathode reference off.
This is the reason I refuse to work on Mesas. It's like they intentionally build amps that are hard to service. The tiny PC traces, crowded components etc. etc...I hate these things. Rant over...
It's probably going to be okay as is, but it is right on the edge. It would be nice if I could calm it down a little. Thanks for any help.
I studied the schematic and was going to change the voltage divider for the bias circuit but then realized that this funky phase inverter circuit that Mesa uses is on the same leg, so any change is going to throw the PI cathode reference off.
This is the reason I refuse to work on Mesas. It's like they intentionally build amps that are hard to service. The tiny PC traces, crowded components etc. etc...I hate these things. Rant over...
It's probably going to be okay as is, but it is right on the edge. It would be nice if I could calm it down a little. Thanks for any help.