Stereo amp debugg

Started by 9 volts, September 28, 2011, 06:55:04 PM

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9 volts


Hope the image uploaded! I'm trying to troubleshoot my stereo. One channel has very little sound and distortion. At the driver transistor (2sc2229) the channel that works has a voltage of
c= 32
b= 1.2(+)
e= 1.8 (+)
The channel that doesn't work properly has a voltage of
c= 32
b= .4(-)
e= .9(-)
When I use an audio probe the signal on the driver (x612 on image) is louder than that on the working side and distorted.
What I'm trying to work out is what is faulty. Eg even though the driver is distorted it appears the have the correct voltage swing (just wrong voltage)
Could the output IC stk0035 be faulty or simply a transistor before the driver x610
I have replaced the electro caps around this area and tested the preamp section