> Agreed 100%. With narrow filters, I notice no difference regardless
> of rise/fall time. The filtering rounds the edges and extends the
> rise/fall time. However, under MDS conditions, I almost always use as
> a wide of a filter as I can, notwithstanding QRM. The wide filter
> provides the most readable copy on faster waveforms, due to the extra
> bandwidth if the transmitting stations is using faster rise/fall
> times.
I use the most selectivity possible (but almost never less than
200Hz) unless the signal is buried in rough noise. The reason is
S/N ratio is directly proportional to selectivity, and my brain has
less to sort out.
When digging out a signal in rough noise (like nearly steady static
crashes) I use a wider filter. In this case I agree making a CW
signal closer match the receiver bandwidth could help. We should
not design for this condition, because it would mean we would
make the life of others miserable a high percentage of time for a
very small percentage of benefit! After all, it isn't anyone else's fault
we have noise!
73, Tom W8JI
W8JI@contesting.com
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