You can only try 🙂 Faults like this are very difficult sometimes and also difficult to try and diagnose at a distance.
When I bolted the PCB back in I managed to get the bias to about 1mv before the current took off.- it should be 7-8mv
`I spent a bunch of time measuring the various test points form the service manual, with a focus on those circuit elements that could affect the bias.
the only meaning full difference was Q15/Q17 where emitter voltages were about -1.8v rather than -2.7v.
I will replace these transistors and check all the passive to get back to where it should be
Will take a few days until I get this done and then will report back
`I spent a bunch of time measuring the various test points form the service manual, with a focus on those circuit elements that could affect the bias.
the only meaning full difference was Q15/Q17 where emitter voltages were about -1.8v rather than -2.7v.
I will replace these transistors and check all the passive to get back to where it should be
Will take a few days until I get this done and then will report back