HI Jim,
the main reason for this preference is that with FSK input to the TRX
you CANNOT overmodulate the SSB of the TRX. Unfortunately this happens
all too often, creating spurii sometimes as strong as the desired
signal above and below the same. In the recent WPX contest here in EU
we had big problems with such a station spoiling up to 20 kHz!
73 de Goetz
dj3iw@t-online.de
----- Original Message -----
From: "Jim Smith" <jimsmith@shaw.ca>
To: <writelog@contesting.com>
Sent: Monday, March 01, 2004 7:47 AM
Subject: [WriteLog] What's wrong with AFSK? was - 5 bit mystery unraveled
> It seems to me that the cognoscenti prefer FSK to AFSK. I have never
> seen any reasons for this preference, probably because I haven't looked
> in the right place. So, what's the problem with just sending AFSK to
> the radio, thereby eliminating the need for an AFSK to FSK converter?
>
> Bill Turner wrote:
>
> >On Sat, 28 Feb 2004 06:50:04 -0600, Bob Naumann - N5NJ wrote:
> >
> >
> >
> >>For the time being, if you want to control your radio, and you want to run
FSK, you will need 2 serial ports.
> >>
> >>
> >
> >_________________________________________________________
> >
> >I wonder if it might be possible to make an AFSK to FSK converter? A
> >simple detector which would be driven from the soundcard output,
> >detecting the mark and space audio tones and converting them to a DC
> >level suitable for driving the FSK input? Perhaps a PLL type circuit?
> >
> >It might miss a cycle or two of the 2125 Hz audio during switching, but
> >I doubt if the timing is that critical. What do you think?
> >
> >--
> >73, Bill W6WRT
> >QSLs via LoTW
> >
> >
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> >http://lists.contesting.com/mailman/listinfo/writelog
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> >
> >
> >
>
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