Gary and all
More radios are a problem on decay because it is the most difficult part of
the problem. When you think about it, it is clear. If the radio gates in
multiple places, it only requires slowing down one point to fix the leading
edge ... while all of the gates must be slowed down on the decay. If any one
is fast, the deed is done.
John K9DX
----- Original Message -----
From: "K9AY" <k9ay@k9ay.com>
To: "Mark Beckwith" <mark@concertart.com>; <topband@contesting.com>
Sent: Tuesday, January 27, 2004 10:30 AM
Subject: Re: Topband: Keying waveform
> 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
>
>
> _______________________________________________
> Topband mailing list
> Topband@contesting.com
> http://lists.contesting.com/mailman/listinfo/topband
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
|
