"John Smith" wrote in message
...
Me:

Oh really, so if part of the waveguide is made resonant at 800 MHz and I
am striking it with a "1KW hammer" it will not "ring" at all? Funny, but
that runs against all I have seen here in the real world...

John

A waveguide can be considered a very wide bandpass filter. Any frequency
coupled to the waveguide, within its pass-band, will appear at the output of
the waveguide. There will be no spurious signals attributed to the
waveguide. As mentioned previously; measurements I have made on microwave
oven magnetrons indicate an extremely wideband, highly unstable signal,
covering hundreds of MHz either side of the nominal 2.45 GHz. The potential
for interference to other services, particularly the 2.4 GHz ISM band, and
to a lesser extent, the 1.9 GHz cell frequencies, is fairly high. It is
doubtful that any significant energy will be present at 800 MHz.

The relative spectral purity of the magnetron measured in
http://www-personal.engin.umich.edu/...laes_tps04.pdf probably
used a laboratory grade 4kV power supply. Note, however, that significant
120 MHz sidebands (and harmonics) are present.

Frank