Industrial Communications Engineers makes a Low Pass Filter that handles
plenty of power without getting warm, doens't upset the SWR much, and
has enough attenuation to pretty much guarantee no harmonics get through
it. My Bencher filter also worked OK, but it got pretty warm at 1200 W
output on cw.
I haven't found myself in a situation where the filter made much difference,
but I live in a very strong TV signal area. I'm sure that in a TV fring
e area the average amplifier would produce enough harmonic power to
cause TVI without a filter. Otherwise, it's a CYA measure to be sure,
but a cheap one.
Scott Ellington
Space Science and Engineering Center
University of Wisconsin
sde@sal.wisc.edu
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