Some TR7s and C-Lines sound exceptionally good. I still recall the sound of
Paul, K4CA who used a T4XC modified for QSK. I once looked at his waveform
to see what was happening and it was a mirror image of what I described in
the old handbook. What's interesting is that the decay looks nothing like
rigs today. Instead, the decay drops sharply to about 50% of its maximum
value then slowly decays out to about 6 mS. In other words, the wave form
takes on the exact characteristic of a charging and discharging capacitor
through a resistor. I found a 1940s QST article written by By Goodman, W1DX
who designed a brilliant grid-block keying circuit whereby the individual
wave form attack and decay controls were brought out to a front panel. He
discusses changing the wave form to best match band conditions! Guys like
By and George Grammer had it all figured out a long time ago...
-Paul, W9AC
----- Original Message -----
From: <n4lq@iglou.com>
To: "Paul Christensen" <paulc@mediaone.net>; <tentec@contesting.com>; "Duane
ACalvin" <ac5aa@juno.com>
Sent: Thursday, January 31, 2002 7:41 AM
Subject: Re: [TenTec] Fwd: Topband: More About Clix
> The most beautiful sounding cw note I ever heard was that of a Drake TR3.
> I can remember hearing it some 37 years ago! Just a few days ago, I heard
> one again and I was overwhelmed. One of these days, I'll buy one just to
> find out what the story is. I've hear lots of TR4's, T4X, Triton IV etc.
> They all sound excellent but nothing like that TR3.
>
> -----Original Message-----
> From: "Paul Christensen" <paulc@mediaone.net>
> To: <tentec@contesting.com>, "Duane A Calvin" <ac5aa@juno.com>
To: <tentec@contesting.com>
> Date: Thu, 31 Jan 2002 07:17:34 -0500
> Subject: Re: [TenTec] Fwd: Topband: More About Clix
>
> > > Both the VI and VI+ reports show risetimes in the 2.0 - 2.5 ms range.
> > > According to the QST reviews, both make statements to the effect that
> > > this is "exceptional" or "excellent" keying waveshape. Perhaps the
> > > understanding of what is exceptional has changed because I note that
> > Tom
> > > Rauch, W8JI is saying 4-5 ms is considered the correct risetime.
> >
> > Correct to the extent that CW bandwidth may be minimized. I don't
> > necessarily agree with Tom's view that the "correct" CW waveform is one
> > in
> > which the transmitted bandwidth is minimized by extending the rise and
> > decay
> > of the envelope and turning the wave edges into a sine-slope
> > characteristic.
> > The problem with Tom's approach is that in minimum signal conditions
> > and at
> > relatively high CW speeds, his preferred wave form becomes difficult
> > read.
> > In essence, the "correct" CW wave form is purely subjective.
> >
> > My preference is for a fast leading edhe in the order of 1.5 mS, and a
> > trailing decay in the order of 5-6 mS, much the same as is often shown
> > in
> > the older ARRL handbooks when grid-block keying is used. This
> > produces a
> > percussive CW note with a slight "bell-sound." No, it is not as
> > spectrally
> > pure as what Tom suggests, but the note is very distinctive and easy to
> > copy. A bit of extra bandwidth can sometimes be a good thing.
> >
> > -Paul, W9AC
> >
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> > http://lists.contesting.com/mailman/listinfo/tentec
> >
>
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