"GregS" wrote in message
...
I was fiddling with a Nad receiver over the weekend. I wanted
to check once again about obtaining an obosolete FM chip
I bought the receiver about 7 years ago. I might have rebuilt the power
amp
section but the FM did not work and the chip got extremely hot.
I figured it was bad. Now 7 years later I fire it up and am surprised
it works. Not getting hot either. I'm thinking 3 possibilities.

Possible short or power supply problem.
Capacitors doing something different.
Spontanious resurection of the chip.

??

greg



A lot of older equipment had loads of tantalum bypass capacitors on the
supply rails, one of which would short. One "bodge" method of finding
these was to send a large amount of current into the power supply rails via
a bench power supply. After a few seconds the shorted capacitor would
dissapear in a puff of smoke, thus identifying the culprit.
The point being that a shorted component might become open circuit any time
later.



Gareth.