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(MaxAluminum) wrote in message . com...

Do you know how to install microwave tubes correctly? If you
don't do it correctly you can cause high levels of microwave
leakage, and I do mean high enough to cause skin burns and
cataracts. And remember, you cannot reliably measure leakage
with a cheap meter! Some will show zero leakage even when
sitting inside a running oven.

Another way to boost microwave power is by increasing the size of
the high voltage capacitor, and at least one Japanese company
changed nothing else in their ovens rated from less than 500W to
about 900W. But if you try this yourself, don't go more than 20%
over the original size.

Your best bet is to put a new one in. It will save money.

I don't see how buying a new overhead or convection/microwave oven
will save money compared to spending less than $50 in parts
(magnatron, capacitor, diode, thermal cutoff), but it certainly is the
only safe and sensible choice for anyone who doesn't know how to work
on microwave ovens.

But to answer your question it is possible to upgrage a 700W to 1000W
in many cases. It takes a combination of the transformer,cap, and
magnatron. Sometimes the transformer is already capable and the
connection on one leg of the input side can simply be shanged. I have
one ten feet from me that I modified. This is too dangerous for
people
to play around with. You need to do it safely and be able to check
for
leaks and monitor it over time.

The problem is that transformers, at least new ones, are usually at
least $70-100, and, as you've warned, if they're not wired right the
person can be killed by about 1,000 volts. On the other hand a
slightly larger capacitor for the voltage doubler is only $5-15, but
simply replacing an old magnatron will usually produce noticeably more
power because magnatrons weaken with use because some old ovens
produce just half their rated power.

People can check their own microwave's output with a container of
water and a thermometer. The idea is to put two cups of water in a
container with a loose lid and microwave it for two minutes. Measure
the temperature increase that took place and multiply by 17 (maybe
it's 17.25 or so?). I mark the ovens I repair so I can check when I
come back.

Is that any simpler than my suggestion of heating exactly 1 quart of
water for exactly 1 minute and then multiplying the Fahrenheit
temperature increase by 70?