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Hey guys, as a shot in the dark I re-soldered all connections on the power amp board and replaced my new transistors with others I had on hand, and somehow, that has seemed to fix the issue. I've put the outputs back in with some new thermal paste and I've had the amp running for a couple hours...

Well, I've tested every transistor on the power amp board, including my new replacements and the outputs again. Every single one tested good, showing normal voltage drops and no shorts.

No problem, thanks for all the help. Fortunately there's not too many of them so I'll post here as soon as I have new info.

Ah thanks. Found them. The leads look just fine to me.

I don't see anything matching that description on any of the boards.

I have not yet, I'll pull and test them when I have a chance.

The red and white ones on the power amp board, right? Those and all the other diodes in the amp look fine.

They all look good to me.

+33 at Q11/12, -33 at Q13/14.

I'm seeing -47v there.

Of course. 6800uF 50v Nichivons. I thought I wired them in correctly.

Yeah, I checked their datasheet and aligned the transistors with the diagram printed on the PCB before soldering.

Yep. Yeah thats what I meant, my bad. Q1-Q4 in the diagram posted by Watthour.

Already did that a couple times, will do again though.

My bad, all measurements are in that order. I assumed the order was implied. Sorry for any confusion.

I have my multimeter in voltage mode, ground lead clipped to the chassis. Turning the amplifier on and touching the red lead to the leg of the transistor/speaker terminal/whatever I'm measuring.

Alright, pulled the output transistors again. A few interesting points: my voltage measurements in the circuit without outputs were exactly the same. I checked the location of the output transistors and they were in the right places. Outputs checked out good once again. Finally, the positive...

My apologies, here's the voltages again: Q1 0.7 0.12 -41.2 Q2 0.7 0.12 -41.2 Q3 0.7 9.7 -47.2 Q4 0.7 9.7 -47.2 Q5 -47.2 -41.2 28.8 Q6 -47.2 -41.2 28.9 Q7 29.6 30.2 32.7 Q8 29.6 30.2 32.8 Q9 29.5 28.8 -33.3 Q10 29.5 28.8 -33.3 Q11 29.5 29.6 33 Q12 29.5 29.6 33 Q13 29.5 29.5 -33 Q14...

Well, it doesn't look good. If I measured right, the 1509 that should be seeing 1.2v at base is seeing 30v. The 777 is seeing 28v at base. The 3503 (replacing the 1451) is seeing 28v at collector. And the 992s (replacing whats labelled as 763s in the diagram, mine had 726s) are seeing 17.5v at...

Hey guys, I picked up a Pioneer SX-636 in good exterior condition a while back and have been working on repairing the thing for quite a while now. When I got it, it barely worked, so I recapped all of the important parts of it, including the large coupling caps, which had bloated like nothing I...