Hi John,
I'm sure we agree the upper and lower sidebands are what allow us to have a
change in signal level. After all, the CW signal is actually amplitude
modulation of a carrier.
I don't see how I could possibly hear passband amplitude ripples of a few dB
as "ringing" or any other deleterious effect, and expect a time delay error
in the sidebands three to five times the rise and fall time of the signal to
be inaudible. Especially when that group error would extend the
time-duration of any sharp noise pulse by the group delay error.
Many people claim broad filters improve copy when weak signals are in rough
noise. This is because the reduction in group delay errors and the increase
in bandwidth allow for less "blending" of signals and noise. What I find is
a filter with less group delay error will allow me to use narrower
selectivity under conditions of weak signals in rough noise.
I guess we have to agree to disagree on this one. I'm firmly convinced
significant group delay errors can make a difference. You are not.
73 Tom
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