No answers yet. I'm still there.
On 6/27/2012 9:05 PM, Alex Malyava wrote:
> Hi Paul,
> Any progress? Anybody answered in 30 minutes?
>
> K2BB
>
> On Wed, Jun 27, 2012 at 8:39 PM, Paul Stoetzer <n8hm@arrl.net
> <mailto:n8hm@arrl.net>> wrote:
>
> Anybody want to try ASCII? I've never made a QSO. I'm calling CQ at
> 14.088.5 MHz.
>
> Paul, N8HM
>
> On 6/27/2012 8:33 PM, Robert Chudek - K0RC wrote:
> > The *BARTG High Speed Sprint* might be an existing (recently
> introduced)
> > contest to make the transition?
> >
> > 73 de Bob - KØRC in MN
> >
> >
> ------------------------------------------------------------------------
> > On 6/27/2012 3:43 PM, Paul Stoetzer wrote:
> >> Somebody should set up an ASCII contest. That would be interesting.
> >>
> >> Paul, N8HM
> >>
> >> On Wed, Jun 27, 2012 at 4:36 PM, Kok Chen <chen@mac.com
> <mailto:chen@mac.com>> wrote:
> >>> On Jun 27, 2012, at 12:47 PM, Alex Malyava wrote:
> >>>
> >>>> Why don't we just invent/introduce some new RTTY standard -
> >>>> the one with 6 bits instead of 5 - covering whole alphabet
> and digits
> >>>> without any FIGS/LTRS and speed it up a little bit to
> compensate an extra
> >>>> bit?
> >>> There is no need to introduce another "mode du jour" even.
> >>>
> >>> 7-bit ASCII (CCITT ITA-5) RTTY has been FCC approved (see part
> 97.309(c)) for a long time now. fldigi supports it, so does
> MultiPSK and cocoaModem, among others.
> >>>
> >>> In a discussion (a year or even longer ago) on this reflector,
> I had shown that for most RTTY contest exchanges, ASCII RTTY beats
> out Baudot RTTY in speed, even when both are running 45.45 baud.
> >>>
> >>> You get rid of the FIGS/LTRS confusion (thus problem with USOS
> incompatibility either; USOS is a Baudot problem), allows lower
> case, and it still beats out Baudot in contesting speed. It is
> when sending paragraphs of upper case text that Baudot wins over
> ASCII.
> >>>
> >>> Because of the Teletype Models 33/35, the popular speeds for
> running ASCII RTTY was 110 baud. At that speed, it will wipe the
> floor with Baudot RTTY.
> >>>
> >>>> Or drop one stop bit to save the length? Or use 3 frequency FSK -
> >>>> shift left is "0", shift right is "1" and middle is
> sync/start/stop ?
> >>> 3FSK may not be a good idea. The reason is that the equalizer
> to compensate for selective fading will be at best very complex to
> build.
> >>>
> >>> 2FSK has the very unique ability to fight selective fading
> with a very simple thresholding scheme. Once you add more tones,
> you can no longer build simple ATC circuits.
> >>>
> >>> For that reason, you will find that there is nothing in MFSK16
> (16 tones), DominoEX (18 tones) or Olivia that explicitly fixes
> the selective fade problem -- they all use long interleaved codes
> to fight QSB in general -- and you may not want to use long
> interleavers with short contest exchanges; the latency will need
> to be over 1 second to be effective. You will need to add latency
> to the exchange time. Selective fading happens quite often. You
> can almost not avoid it with a Rayleigh path.
> >>>
> >>> Anyhow, the solution is already at your fingertips, and the
> FCC has blessed it for years now. It is called ASCII. And 110
> baud with 170 Hz shift is a breeze.
> >>>
> >>> 73
> >>> Chen, W7AY
> >>>
> >>>
> >>>
> >>>
> >>> _______________________________________________
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> >>
> >
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>
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