Henry, dont laugh at this method..it works....read it thru before nixing it.
I have had this happen before too. simply put about 5 volts at 500 mils on
the b+ line, regulated at the 500 mils. Let it sit for a few minutes and
then go looking for the part to be running warm. The part will be
dissipating 5*.5= 2.5 watts of heat. sooner or later the bad part WILL get
warm. It will NOT lift traces unless they are VERY small.
If this approach fails, the next thing I do is go in with a new(sharp)
razorblade and start as far away from the power supply and cut B+ traces one
at a time until the short goes away. This isolates the short to a smaller
area.
Suspect Tantalum caps as they usually fail in this mode of low ohms
shorts...let us know when you find it...Eddie
"Henry Kolesnik" wrote in message
...
Sometime ago I think I recall someone posted or wrote an article on a neat
way to isolate a shorted component on a pcb using common test eqpt but I
can't recall the methodology. I'm trying to find a shorted component on
a
Wavetek 188-S-1257 signal generator. The B+ line reads about 0.4 ohms and
I'm not having much luck disconnecting componets. I don't have a
schematic
and my eyes ain't what they used to be for tracing and I want to minimize
the unsoldering. Does anyone recall the article or have a good way?
tnx
hank wd5jfr
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