Lent a buddy my '82 blonde 110 RD50 on Sunday for an all day jam session I hosted locally. You can read about the amp here:
About an hour in, the amp stopped working. It remained powered on, but no sound that we could hear.
After the jam, on closer inspection at home, I found the following:
* Reverb control acting as Master Volume (but volume is extremely low with much hum)
* Clean and Limiter side controls work but just barely discernible, and only when Reverb control turned up
* Bright and Clean/Limiter toggles work
* Eliminated tubes, speaker, speaker cable, footswitch and reverb tank as culprits
Starting checking for continuity and bad components with my audio probe, signal is passing in preamp section except lower volume when compared to my "good" RD 50. Also weak and distorted coming out of R26.
Swapped all ICs with known good, no change.
First guess is that either the signal is not getting to the power amplification section (bad resistor or cap) or something is wrong coming out of the power section.
Plan to test voltages tonight.
If anyone has experienced this type of failure appreciate any insight.