William Sommerwerck wrote:
"Cydrome Leader" wrote in message
...
William Sommerwerck wrote:

What do you mean by excessive? If a magnetron can be modulated
by varying its B+, why shouldn't each PWM cycle be just one or two
seconds long? You DO NOT want the magnetron running at full power
for "long" periods, followed by even longer periods off (eg, one minute,
four minutes off, for 20%).

If you like switching a kilowatt sized transformer on and off every
second, power to you. Same for a reed relay rated at kV at hundreds
of mA.
It would obviously be easier with one of those switching power supply
microwaves, but that's not how the old microwaves worked.

As far as I know, my 10-year-old GE is a "newer" model.

This has become one of those "inquiring minds want to know" questions. There
are leakage meters, which would show changes in level. Does anyone make a
power meter you can place in the cavity?

You might get by with a cup of water and a light bulb. Neon lights with
the leads twisted together was the standard "indicator" for microwaves
when I last touched these things. You really want the cup of water as a
dummy load when putting weird stuff in a microwave.

I just ran at test like that on my made in 1981 samsung microwave. It
surprisingly has a digital clock and numeric keypad- space age stuff for
the time. This thing was clearly made when they were terrified of
microwave leaks. There are a whopping 20 torx screws alone holding the
glass in the front door, plus more holding the door together.

Anyways, in defrost mode, the magnetron is clearly cycled on and off in 15
second intervals. I could tell when it was on from when the small
lightbulb lit up.