On Sun, 07 May 2017 10:27:51 -0700, Jeff Liebermann wrote:
Model number? I couldn't tell from the photos.
8566B (this its display unit counterpart)
My guess(tm) is the big electrolytic filter cazapitors are shorted,
causing something between the line cord and the caps to smoke. Smoke
usually means some resistive device burning up, although it can be a hot
trace scorching the PCB. The color of the smoke would be helpful.
Black is carbon comp or oil, white is plastic wire insulation, gray is
phenolic, brown is epoxy or a dead mouse or insect infestation. There
are smells associated with each one that is recognizable. I had a mouse
take up residence inside an HP sweep generator last fall the
demonstrated gray smoke and a horrible stench. If you can't find the
source of the smoke or smell, shove one end of a 1/4" ID vinyl hose up
your nose, and inhale while moving the other end of the hose all over
the device. (Yes, I actually do this). It takes some practice and
fortitude. For a mouse, have a vomit receptacle handy. You won't find
any of this in books on electronic repair.
There was not really any visible smoke to speak of, Jeff. It was
primarily the smell that indicated something had gone phut. Smelled like
toasted PCB, but I can't see any burned areas at all. Might be a
different story if I tore it right apart but so far as I can see, which
is like 90% of it, nothing.
One thing I can say is it's *definitely* not due to any infestation!
Funny thing was, I couldn't detect the slightest smell at all after
removing the covers; it was a very transient event with no noise either.
If you're dealing with very small amounts of smoke, that's either
invisible, or pervasive (smoke everywhere), I suggest one of these
airborne particulate detectors:
http://802.11junk.com/jeffl/Nikken%2...ity%20Monitor/
Nikken-AQM.jpg
http://802.11junk.com/jeffl/Nikken%201394%20Air%20Quality%20Monitor/
My office was filled with smoke when I arrived one day and I had no idea
where it was coming from. The Nikken "air quality" detector found it
fairly quickly.
I shall look into those links; many thanks.
If you have money, consider buying an IR camera.
Yes, they're clearly very useful to have around. I'll see what's
available here in the UK.