>
> I don't understand what you mean by "bell like". Do you mean the
> shape or the sound?
The sound...not the wave shape. The exponential decay produces this effect
and agreeably at the cost of added bandwidth.
> Nothing can sound better than it sounds after running through all
> the filters anyway, so unless you and everyone else are using SSB
> filters you might as well clamp the transmitter keying waveform at
> 250Hz.
I use 1.8 kHz and 2.4 kHz filters most of the time and let my ear filter out
most of the interference. I much prefer the articulation of non-filtered CW
signal even in the face of QRM. However, if QRM becomes too difficult, then
I'll load the 500 Hz and 250 Hz filters.
> Only if you use a wide filter. I sometimes use a 2KHz filter during
> lightning storms in my FT1000 because the group delay in the
> narrow filters is horrible (causing ringing, by making the parts of the
> sidebands of the signal out-of-phase with each other), but that only
> works when the band is empty around me. Someone would be out
> of their mind using more than a 500Hz filter during a contest, or on
> a crowded band!
I'll disagree here. You're used to lattice filters in the Yaesu. The
Ten-Tec filters are ladder designs which exhibit very low ringing even when
selecting 500 Hz and 250 Hz filters. By comparison, when I owned a FT-1000D
and Kenwood TS-950SD, I could not tolerate the narrow lattice filters,
particulary on the Kenwood. Given good crystal filters, there really is a
difference.
> Perhaps if I listened through a 2kHz filter more often I'd grow to like
> hard waveform signals, but to transmit them the people listening to
> me would have to use wide filters also...otherwise I'm just wasting
> space.
That's understandable. Using narrow lattice filters makes all CW signals
sound soft due to ringing.
> Looking at a scope will get us in trouble every time.
But it's the tool within reach for most of us. For example, had I not had a
scope, I would have never detected that the my amp was slightly
hot-switching on the trailing edge. The clicks were there, but not
overwhelmingly apparent. Because of the scope, I decided to find a better
timing point in my transceiver to avoid hot-switching while keeping the QSK
T/R turn-around time fast. We can't see what happening in the frequency
domain, but at least we can reasonbly correllate what we see on the scope
with what's going out over the air.
-Paul, W9AC
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