I am working on the preamp of an AU-717. I am using a scope and started doing a signal trace through the preamp and found when I check the collector on tr01 for the left channel, the channel starts working for a moment or two, the waveform is clipped, and then fades out again. Are you familiar with the circuit? I am suspect of the xsistor, or am I trundeling down a rabbit hole. I have started a thread "AU-717 Dead channel". most that have replied say clean the switches, etc. i have already done that to no avail. The amp section is fine. Any help greatly appreciated.
Cheers,
Darrrell