On Fri, 26 Sep 2008 23:00:09 -0700 (PDT), poster
put finger to keyboard and composed:

if the transformer secondary was shorted inside it would not be able
to supply voltage high enough to burn the rectifier diode when it was
replaced so maybe wiring is a good suspect since magnetron seems ok-
that could be tested with turning on grill operation only ?

I agree that the transformer is probably OK. All I can add is that
whenever I've seen a failure in the protection diode, I've always
replaced it and the rectifier diode as a pair, and I've tested the
magnetron and cap. I can't see what else could cause the protector to
fail.

BTW, I don't understand how you can confidently state that the
magnetron is good unless you've tried it in another oven.

- Franc Zabkar
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