I have followed the thread about narrow filters with interest, but I
note that no one has mentioned using very narrow filters on
PSK31. The theoretical bandwidth of this slow mode is 50 Hz.,
and I do not know if the ringing would bother PSK decoding. I
would love to try 100 Hz. filters in my Omni VI, or even the 250 Hz.
filters, except I am too cheap to purchase them. I expect that the
effectiveness of this combination will be evaluated by someone
using IF DSP, when a manufacturer finally includes extremely
narrow filters.
There is the question of whether there is a meaningful increase in
S/N using extremely narrow filters. Of course, there may be a
problem with drift and losing the other guy, unless both stations are
using extremely stable VFOs, and I do not know if the Omni VI
would suffice here.
73,
Jan Ditzian
KX2A
kx2a@arrl.net
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