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Mark D. Zacharias[_2_] Mark D. Zacharias[_2_] is offline
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Default JVC RX-8010V Shutdown


"LOP" wrote in message
. ..
I am working on a JVC RX-8010V Receiver. The set powers up for about five
seconds and then I hear a relay click and it shuts down. I have changed a
few electrolytics here and there with high ESR but the problem persists. I
am also working at the moment without a schematic. Thought that I would
check the Group to see if there may be common problem with this receiver
before I try to find a schematic.

Greatly appreciate any help you can provide.

Don and Liz


Normally one needs a service manual to troubleshoot a problem like this, and
experience with troubleshooting relatively complex audio and power supply
circuits is also essential.

Most likely a DC problem of some sort - either a single amp channel has a DC
offset, or a regulated power supply stage has malfunctioned, the likely
result of which is a DC offset at all amp channels, or simply that the
microprocessor-controlled protection circuit has detected the power supply
fault.

There is also a chance of a blown amp channel, shorted output transistors,
drivers, resistors, etc. The protection circuit would also be triggered by
this, though good design practice would suggest a faster shutdown in this
situation. Yamaha receivers for example shut down in less than 1/2 second in
an over-current scenario.


Mark Z.