SONY ZX66i No Sound ... confused

[repair-it]

Need help from Audio Expert troubleshooting a no sound fault (everything else works) SonyZX66i https://www.manualslib.com/manual/15...page=57#manual

I replaced the STK 412-150 chip. I have no voltage on ic pin 16 (bias) & no negative voltage on pin 12 which is probably why the bias is 0. I checked the voltages on Q610 and have 71v on both base & emitter but 0v on the collector.

I'm not sure where the missing negative voltage on the collector should come from. Does it mean that the transistor Q610 is bad?

[R_J]

Re: SONY ZX66i No Sound ... confused

Is the base voltage on Q610 around .7v lower than the emitter? if not, check the Mute control circuit Q606, Q604