S-Man
StrivingON
TBH non-powered fault finding is tricky, it's often hard to interpret the readings without removing some transistors. Therefore, you another approach in to lift one end of the feedback cap (so you don't damage it with the excess voltage), the amp will still bias up properly, although it will not amplify any audio. Then you can go back to powered fault finding - especially if you have the safety resistors fitted.
If you want to go this way:
1st check the voltage across the 68uF across TR5 - if it's >6V power down and remove it!!
2nd, write down on a schematic the dc voltage on every node in the amp (all relative to 0V) and post it on here.
Option 3: Remove all the transistors and polarised caps. Measure all the remaining components in situ and then replace all the trs and polarised caps with known good ones.
If you want to go this way:
1st check the voltage across the 68uF across TR5 - if it's >6V power down and remove it!!
2nd, write down on a schematic the dc voltage on every node in the amp (all relative to 0V) and post it on here.
Option 3: Remove all the transistors and polarised caps. Measure all the remaining components in situ and then replace all the trs and polarised caps with known good ones.