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Mark D. Zacharias Mark D. Zacharias is offline
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Default Yamaha receiver.

Mark D. Zacharias wrote:
Dani wrote:
RX-V975A no display, relay clicks, & shuts down. Very hard unit to
work on. You have to
scrap these units, just to solder a few bad connections. Can't find
anything online.
Anyone work on one of these? Thanks, Dani.


Doesn't look like a valid model number. Could it be

RX-V795?

Those of us who have had the (mis)fortune of having to work on
surround receivers these past few years have mostly learned to work
around the obstacles.

You can rig a double-ended AC cord (use ONLY polarized ends, and make
sure they match end-to-end).

Plug the receiver's own AC cord into one of it's switched outlets.
Plug your double-ended cord into the other switched outlet. This will
bypass the relay. If everything pretty much works normally, the relay
problem is confirmed.

Remember: The AC cord polarity must match or there will be MAJOR
sparks, since the AC line would be shorted if they were reversed. For
this reason, only an experienced tech really should attempt this.


Mark Z.


P.S.

This method can also be used to check DC offsets and all internal power
supply voltages, regardless of protection status.
For this reason, it is important to make sure you don't have a blown channel
or some other high current draw before going too far with this method. A
variac is most useful in this regard.

Mark Z.