On Tue, 21 Feb 2012 20:48:19 -0600, amdx
wrote:

I have small microwave and it seems the power is getting less and less
as time passes. Do Magnatrons wear out?
Mikek

Yep. The thorium oxide coating on the cathode slowly "evaporates"
away. Another cause is a sloppy filament winding which sometimes
produces odd oscillations.

The rated life for consumer magnetrons is about 2000 hrs. If you live
on 5 minute TV dinners, that's about 24,000 dinners.

You can check your microwave oven output with a simple calorimeter.
http://www.gallawa.com/microtech/output.html
http://www.zyra.info/micropwr.htm
http://www.eletrodomesticosforum.com/es/cursos/horno_microondas/Inverter.pdf
(see Pg 16). This isn't IEC 705-88 but is good enough. The
instructions are not very clear as to how to make the measurement. You
do NOT cook the thermometer. I made this mistake once. The end blew
off, spraying the oven with broken glass.

Mumbo-jumbo on the topic:
http://www.ehow.com/info_12020972_microwave-ovens-lose-power-time.html

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# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
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