Once again, Jerry, you are giving advice based on general assumptions on
equipment you obviously have no specific knowledge of and misleading
another
poster.

Amen!

Mark Z.

"Leonard Caillouet" wrote in message
news:8s4%d.70006$SF.30384@lakeread08...
Once again, Jerry, you are giving advice based on general assumptions on
equipment you obviously have no specific knowledge of and misleading
another
poster. Yamaha sells manuals rather inexpensively and sells parts to
anyone. Dealers and ASCs get discounts, and only ASCs get access to
training info and tech support, but you can buy nearly any of their audio
manuals for about $18 retail and their people are very helpful about
looking
up part numbers.

It is unlikely that the unit is not worth repairing as it was one of
Yamaha's more expensive subs.

Leonard

"Jerry G." wrote in message
oups.com...
Check for any high ESR or shorted caps. These do cause problems with
the output drive tansistors.

The switching supply transormer may be damaged if the switching
transistors were shorted. I have seen this before in other similiar
units.

Unless you are an authorized service rep for these products, I doubt
Yamaha will sell you the parts or service schematic. You may have to
send them the unit to have it serviced. If the unit is not a very
expensive one, it will pay to replace it.

Jerry G.
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