Sony XM-7547 muted- schematic error?

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Maybe my eyes aren’t working properly, but page 14 of the service manual for this amplifier has the mute control circuits on it and it’s showing 26 volts on Q812. Where the hell is 26v coming from???

The only thing that transistor does is forward bias the octet of ‘line sw’ transistors in the front end which will allow a signal to pass (not muted), when mute is active they have negative voltage at their bases to keep any signal from passing. But again, I can’t see where Q812 is sourcing 28v from. It’s definitely biased off which is why I have no sound, but I’m currently scratching my head.
 
Not sure which points you mean...

If you’re looking at the schematic, wire 7 at the top of page 14 comes out of the mute circuit and heads over to page 11 where the muting transistors live. When mute is active the bases of the 8 transistors on page 11 sit around -13.5v, which shuts them off and kills the audio.

With mute inactive you get like 24v or so at the same place, thus switching the transistors on and allowing audio to pass.

Just noticed another schematic error- The neg voltage for the transistor bases comes from apparently 2 places: there’s a 1-meg resistor from the -15v supply (R882 on page 14), and there’s another 1-meg on page 11 labeled R882... I believe these are in fact the same resistor, it wouldn’t make sense to parallel a pair of 1-meg resistors when you could just as well have used a single 470k. Guess Sony didn’t pay much attention to their drawings, luckily it was close enough to figure this one out.

Drawing also shows a fan and associated driving circuits on this model amp, mine doesn’t have that stuff. Not sure what’s up with that, I know the 5-channel one had a fan.
 
Yes, it’s there all right just like the schematic says, but I still can’t tell where it’s coming from. I think there must be a trace that’s not easily seen or something, I’m just glad I didn’t have to try and figure it out. There are numerous silkscreened lines and reference designators all over the board, a small trace could easily be hidden under all that. As for the schematic, I’m sure it’s just a simple error.
 
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