OK the history I purchased the amp awhile ago it broke I was able to repair it with some help worked great. One day it didn't sound right anymore so I scoped both channels at low volume rt channel looked great nice rounded peaks lt channel the peaks on top matched the rt ch the peaks at bottom went flat and rough about halfway down from the middle. So OK opens it up checked the outputs rt side all 10 OK lt side 5 OK 5 shorted upon further inspection found what I believe is the driver transistor shorted. I removed it now the 5 shorted outputs aren't shorted but they are still bad.
. This pic is actually of rt channel (part # reference) I cannot find a replacement I asked the last owner for some help he said the part# 2SB1426 was discontinued. Then I decided to check more areas for bad components and found the famous sip card failure .
all 3 pins from Q1 and Q2 came loose from board but I was able to repair with heat and a small touch of solder
not a good angle but you can see that Q2 is elevated off the board I did the 100ohm resistance tests and it passed I also found R164 out of spec so I compared everything from rt to lt in the audio section these are the only issues I found I thought the 10 ohm resistors by the RCA were replaced previously by someone with 20 ohm but tested way out of spec I already have those also realized my discontinued part and my sip cared issue were on different channels so on one side bad outputs and the transistor that I can't find and 1 small resistor out of spec on the other channel just the sip problem and the 2 10ohm resistors
What I need help with is a replacement part for the discontinued transistor, the wattage of the small resistor at R164 and any help your willing to lend me I am a beginner at amp repair . I purchased Perry's tutorial so I have a lot of reading and learning to do any and all help will be greatly appreciated.
What I need help with is a replacement part for the discontinued transistor, the wattage of the small resistor at R164 and any help your willing to lend me I am a beginner at amp repair . I purchased Perry's tutorial so I have a lot of reading and learning to do any and all help will be greatly appreciated.
Sorry it's been a few days I tore my rotator cup in a 4 wheeler accident. Ok I powered it up with a 10A fuse and the fuse lit up like a light bulb so I quickly disconnected power. I didn't get any smoke thankfully. Ok so this amp is my pride and joy I treat it like its one of my children, I don't feel like practicing on this one. Recommend anyone to repair it for me I just want it working the way it should and I have know idea what the previous repairman did but a bunch of components don't match from one side of amp to the other. I also need my smaller PC4400.2 repaired as well. I'll pay for it to be correctly repaired like I said I don't want to practice on this one. Thanks Perry
Sincerely, Derek
Sincerely, Derek
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