Mike said:
>I would use bandpass coax stubs to keep harmonics down with
>only an "L"network.
For some reason (advancing age?) I forgot to mention the 'half wave filter',
popular back in the early days of dealing with TVI. Being an electrical half
wave, it reproduces the load impedance back at the input terminals, and by using
coax stubs to provide the capacitors, can be made to handle high power. A simple
LPF when matched at the output shows a mismatch at the input as cut off is
approached; to avoid this and get satisfactory attenuation, more sections are
needed. The half wave filter by reproducing the output impedance at its input
can provide a better match for a given number of poles and attenuation.
73
Peter G3RZP
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