Mark and all,
This waveform is, as Tom notes, a classic example of shaping with an R-C
time constant. The leading edge will not likely cause clicks, but at the
turn-off point on the trailing edge the corner can be pretty sharp -- and
cause serious clicks.
Late in the past weekend's contest when CW speeds slowed down, it was easy
to analyze clicks. Most radios with clicks seem to have them at both
transitions, but a few were only on the trailing edge. Subjectively, I find
bad trailing edge clicks to be the worst -- There are so many common events
with a hard attack followed by a decay (e.g. ringing bells) that this
"reverse" pattern is particularly annoying.
73, Gary
K9AY
___________
> I have posted the photo of the CW waveform out of my handbook to head off
> any potential misunderstanding. I think at some point the ARRL probably
> started using a different photo. This one I have posted out of the 1975
> ARRL Radio Amateur's Handbook meets all of Tom's criteria:
>
> http://home.swbell.net/swca/radio/handbookcwwaveform.JPG
>
> The accompanying text claims it has 5ms rise time, and you can plainly see
> the rounded corners, er, I think? Tom, am I misinterpreting this photo?
>
> Mark, N5OT
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