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Amplifier Problems With a Sansui QRX-9001

Finally for tonight, need to verify dc voltages on the power supply board that feed the two amplifier cards. Schematics show pins 55 and 56 with +43 and -45 vdc. should also be able to take that reading on pin 3 and 11 on the card itself again be careful not to short out two pins bad things will happen.
 
I do not get any voltages on pins 3 and 11 on the amplifier cards. I can’t seem to find pins 55 and 56 on the power supply board.
 
Ok, into the power supply. Find F01 and F02 (fuses) take AC voltage readings from each end to ground. the fuses will be hooked to the purple wires from the transformer. Should measure about 38vac probably a little less if on a dim bulb. We are tracking voltages from the transformer through the power supply at this point and will end up at the dc output leads to the driver cards. After that we will work through the diode strings and transistors.
Well done with the following along so far sir
 
Yeah, I’m not super knowledgeable on troubleshooting, but I enjoy the process. Also beats taking it to a tech with the prices, and availability/waiting times.
 
Great, now need voltage readings DC Volts at the collector of TR01 and TR03 to ground. Careful here, insulate all but the tip of the probe, a slip would be problematic.
 
correct values, now do the same for the emitters tr01 and tr03

then repeat for the collectors and emitters of tr02 and tro4 (should be negative values)
 
both sides of R602 to ground looking for negative readings off the D602 diode. TR602 now looking suspect should be the 2SB560 --- replaced by KSA1220AYS as a heads up.
 
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