On Sat, 08 May 2004 13:13:36 -0700, mike wrote:

Eric R Snow wrote:
Greetings All,
My microwave oven just quit heating. Before I scrap it for parts maybe
I can instead fix it. When set to defrost the power cycles on and off.
And you can tell by the lower fan sound and the light slightly dimming
when it is supposed to be heating.. It still does this but nothing
gets hot. Whether defrost or full power. So, I think the transformer
must still be getting power. Any thoughts? Do magnetrons eventually
fail? I have another oven that's over twenty years old and it still
works fine.
Thank You,
Eric R Snow

You've been given a lot of GOOD advice NOT to work on it if you don't
know what you're doin'. You can kill yourself even if it's been off
for a long time.

I'd vote for a bad diode or cap. Mine has fuses that blow when the
diode shorts. No, you need to put some volts on the diode to test it.
Typical meter on ohms doesn't put out enough volts to turn it on.
Of course, if it's shorted, you can see that.

Remember, the cap can kill you!!!!! If you think you can check the
cap for volts with your meter, think again. Cheap meters will blow up
on a fully charged cap. You'll hurt yourself on the sharp metal when
you come flying out of the case. Make sure you pee before you start.
Smaller wet spot to clean up...assuming you live.
mike
I should have said I know about how to discharge a cap. I know that
dangerous voltages (lethal) can be stored a long time. I won't be
sticking a crappy VOM or my fingers or anything else conductive where
it shouldn't be. I won't be doing anything with the power on. I won't
be pointing the magnetron at my crotch. What I would like to know is
if there is something I can check after the HV xmfr with a VOM. If
not, then it gets trashed. (I do need another xmfr for that spot
welder). Thanks for the warnings.
Cheers,
Eric