This is the method that Collins used to generate CW on the Collins KWM-2.
It also explains why the sidetone frequency of the KWM-2 is so high (1500
Hz). Typical audio oscillators generate harmonics that are not sufficiently
attenuated to support this method of CW generation, so rather than design an
ultra-low distortion audio oscillator, Collins put the sidetone frequency at
1500 Hz. This kept the audio oscillator/sidetone second harmonic out of the
filter passband, assuring a clean CW carrier. It was a clever idea, but how
many CW ops want to copy a 1500 Hz tone?
Scott
N7NB
----- Original Message -----
From: "Mike Hyder -N4NT-" <N4NT@chartertn.net>
To: <tentec@contesting.com>
Sent: Wednesday, July 25, 2001 19:06
Subject: Re: [TenTec] Re: Ten Tec Stations
>
> Assuming the tone does not drive the rig into distortion.
>
> Mike
>
> ----- Original Message -----
> From: "James Duffer" <dufferjames@hotmail.com>
> To: <jimr.reid@verizon.net>; <N1EA@qsl.net>; <tentec@contesting.com>;
> <k8do@msn.com>
> Sent: Wednesday, July 25, 2001 5:51 PM
> Subject: Re: [TenTec] Re: Ten Tec Stations
>
>
> >
> > Assuming carrier is suppressed, and further assuming the unwanted
sideband
> > is filtered out, then if a single sinusoidal tone is used to modulate a
> ssb
> > transmitter.....the output will be a CW. Legal too.
> >
> > 73, Jim, wd4air
> >
> > >Well, after reading through the stuff on the site, it seems to
> > >me that this program does not/could not actually key up the
> > >CW of a Ten Tec HF rig. What it appears to do is put out
> > >audio tones of CW which are then used to FM modulate
> > >a repeater. Unless the VOX is somehow used in the Ten Tec
> > >rigs to do CW keying, I don't think it would work. Of course,
> > >I guess the program could be used up in the phone portions
> > >of the HF bands to do CW "simulation" along with voice
> > >annotations, but that isn't what I had in mind.
> > >
> > >Now maybe I am wrong and don't understand. And, I think
> > >that is the sort of CW that programs such as Hamscope,
> > >now popular for PSK31 also do when"transmitting" CW.
> > >
> > >Would this sort of "tone" CW be legal down in the CW segments
> > >of the bands; as PSK31, which is also SSB tone modulation
> > >and is "legal" as a "digital" mode?
> > >
> > >Lots of questions.
>
>
>
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>
>
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