Amp if Fixed!!! Playing music on all 7 channels.
Strangest repair I have had, possibly ever. After all the voltages and DMM testing of the transistors seemed to be good, but still going into protection with speakers connected (a load) I was getting frustrated and resorted to some guessing and shot-gun parts.
Best part is my first guess and set of parts repaired the amp. Looking back at my posts, couldn't figure out why it only happens with current, so I thought I'd start with the Input pair, thinking one may be bad and it's causing the amp to go out of balance and high DC. Pulled out the first (2) pair from channels 1/2 and guess what they both measured perfect on the DMM and the multi-tester, showing ~600mV Vf and ~1000 Hfe - right in line with the datasheet.
On a whim, had it apart so I might as well shot some parts at it - I put in (4) pairs of matched (with multi-tester, double-checked Hfe with BK Precision DMM) - and it powered up and played music first time!!! Had 8mV DC on one channel and 170mV on the other channel. That's fine, because at least it was playing and I could do some actual testing now. Proceeded to replaced the input pairs on all the other channels. Tested each channel individually and they are all working outside the case (which I couldn't get them to pass music without protection kicking in previously)
So success - except I still had 170mV of DC on channel 1/2 board - remember when I said these ribbon cables are the worst and most prone to failure on these amps, my opinion is proven again. Granted this is the board I have pulled out 4-5 times between cap replacement, resoldering and voltage testing, but nonetheless they should be flexible cables with connectors, not ridged ribbon cables.
Well apparently one single wire was loose on the AMP2 (top RCA channel) and in the process of finding it, 4 other wires broke - so actually good thing I had an issue to resolve, because it would have failed someday. But unsoldering, stripping and reinstalling those two ribbon cables takes at least 20-mins and very tedious delicate work to strip the wires without breaking the wire in the process, then you have to feed 11 and 12 wire ribbons into the output board and the input board carefully lining up the wires with the holes and then solder without any of them pulling out. Like I said - tons of fun!
Hoping this thread helps somebody repair their PVA-5 or 7, and maybe even their bigger brother MCA-5. I would think they are all a similar design, with different voltage parts and number of outputs.