Some of the recent postings have me thinking about 1/4 wave bandpass
filters. I know they have dozens of uses but I've never used one except
in microwave amplifier designs. I was wondering if they are commonly
used for transmit and receive filtering in single band applications.
I own an ICOM IC-756 which I believe probably has a rather wide front
end bandwidth. I can't find any documentation to confirm the bandwidth
one way or another, but I often experience receiver overload by
presumably nearby signals. I believe these over load "bursts" are either
another amateur station on a different band, or maybe RFI from a non ham
neighbor (or maybe even something in my own house). Would a coaxial
shorted 1/4 wave stub BPF help this situation? What's a typical
bandwidth that they produce? Since it's an open circuit at the filter
passband center frequency, does it matter where along my feedline I
locate it? For multi band operation can I use several of these with rf
switches, or is there some better way to handle all of this?
thanks,
Dave
K0QE
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