Pioneer VSX-827 -k

[Dicko101]

Hi everyone, I just picked up a pioneer HT 7.1 reciever for nothing because it isn't working, when you provide an input signal on any of the inputs, including tuner, there is a very low volume, heavily distorted output on all 7 channels, I presume it would be a fault in the power circuit given that it affects all channels, any advice on how to trace the problem? I have an Oscilloscope, multimeter, signal generator and other gear but not a lot of experience. Thanks for any help.

 

[(*steve*)]

The first thing to do is to try to get a service manual.

However, you could also measure the power supply rails and see what you've got. It may well be that there are voltages marked and you can compare your readings to them.

Be very careful that the power supply is likely to be a switch mode device with mains voltages all through it. They can kill you (sometimes even after you've turned them off).

 

[elebish]

Hi everyone, I just picked up a pioneer HT 7.1 reciever for nothing because it isn't working, when you provide an input signal on any of the inputs, including tuner, there is a very low volume, heavily distorted output on all 7 channels, I presume it would be a fault in the power circuit given that it affects all channels, any advice on how to trace the problem? I have an Oscilloscope, multimeter, signal generator and other gear but not a lot of experience. Thanks for any help.

After checking the power supply rails for proper dc voltages, the next logical point would be the pre-amps. It is highly possible that an LSI is used (large scale Integration). A commonly used type would be an STK350-430. Trouble shooting a malfunction like yours is not easy due to the small scale components used. Just one slip-up with a probe can do more damage than the original malfunction. I just repaired such an animal and it is not for amateurs but that is up to you! Good luck!