Summertime on 75 and 160 is a good time to compare filters. Another more
scientific way is with a local pulse generator without antenna and see
what the maximum pulse rate with fixed pulse width that you can make out
the pulses before they turn into hash. With most filters, that's fairly
slow, though my best receiver for that condition is a crystal controlled
converter with a BC-453 as a tunable IF. The pass band is Gaussian, not
square and that's great for passing pulses with the least damage. Any
nondigital filter with a square response curve is constrained by laws of
filters to have a lot of ringing. Low ringing can only be achieved with
as square frequency response with many many poles, far more than are
practical with crystals, but are workable in DSP.
INRADs filters may not be the ladder filters of Tentec. Ladder filters
are not generally symmetrical unless of very narrow bandwidth compared
to the center frequency. SSB at 6.3 MHz is not narrow compared to the
center frequency. Are there transformers in the INRAD filters?
73, Jerry, K0CQ
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