Nothin about this amp visually appears blown. Using my heat camera I cant find anything running excessively hot either but I'll excersize that technique a bit more. Getting stumped.
In addition to heat testing, Im going to carry out more tests of IC241.
Are you thinking one or more of the ~12 pre/driver transistors one may be failing?
In addition to heat testing, Im going to carry out more tests of IC241.
Are you thinking one or more of the ~12 pre/driver transistors one may be failing?
Transistors (or any component) that run really hot (especially where there is a discoloration of the board) are suspect.
If the output of IC241 is a clean square wave, it's likely OK.
You stated that touching a point on the drive circuit with your scope cleaned the output up. Could you use one channel to make the output better while watching (with the other channel) various points in the drive circuit up to the output gates to see how each point of the drive signal is changing?
If the output of IC241 is a clean square wave, it's likely OK.
You stated that touching a point on the drive circuit with your scope cleaned the output up. Could you use one channel to make the output better while watching (with the other channel) various points in the drive circuit up to the output gates to see how each point of the drive signal is changing?