Topband: bandpass filters

[Tod -ID]

Based on those curves I would suggest folks get W3NQN's articles about RX
filters and build one of them. The results should be a lot better in
squashing the BCB signals at 1700 kHz and lower. They attenuate quite well
above 2 MHz too.

There is nothing wrong with the ICE filters -- it just that with a very
small amount of effort one can fabricate filters that are much better using
stuff that has appeared in QST and elsewhere. If you have patience you don't
even need a spectrum analyzer -- just a signal source, a general coverage
receiver and some time.

I haven't posted anything for 160  meters but I do have links to downloads
of the two key W3NQN articles and some pictures of an 80 meter BP filter
that can handle 200 watts. [a bit of overkill for RX]. There is also a
spectrum picture of the performance of the filter I built for 80 meters. I
did build filters for 160, 80, 40, 20 and 15 using the same methodology. The
160 meter filter performs very well too; I just haven't put the sweep of the
band pass on my website.

The URL is http://www.k0to.us/HAM/Receive_filter/rxfilter.htm

Tod, K0TO

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