Hans says:
>Is not a high pass filter terminated into 50 ohms a better solution then a
>low pass filter? The latter is only maybe seeing 50 ohms on one frequency
>and on harmonics looking into something else than 50 ohms?
Misterminating a filter in its stop band has relatively little effect on its
performance. This is because filters reflect the energy applied to them when
that energy is on a frequency in the stop band. Depending on the filter, they
can have a poor SWR in the passband too, but that's another matter. Worth
looking at the Handbook of Filter Synthesis by Zverev.
Of course, I'm talking here of classical passive LC filters, not active or
digital ones, which can do things passive LC can't - like inverse Tchebycheff
characteristics.
73
Peter G3RZP
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