Ty,
Please note, that I did not mention that it was a good mode for contesting or
Dx'peditionning...
Like MFSK16, and due to FEC and interleaving, you need some time for the message
you enter to appear on your correspondant's screen. It is also probably
unadapted for "pile-up"...
But isn't there a life outside contests ?
Pat.
PS: Think it is idealy suited for 6m. for example... so far you had no
alternative to CW for Aurora tfc... and a lot of space on 6 !
Also the sensitivity of the slow modes make them interesting for tropo and
Iono-scatter... Yes it is less sensitive than JT65, but you are not limited to
call and report exchanges, and don't have the time-synch problem...
Quoting k3mm@comcast.net:
> Ahh... OK, well that's sounding better at least...still slow for contesting
> (what else is there??)
>
> How hard is it to tune in manually, or how fast does it lock on for an
> autotune?
>
> Ty K3MM
>
>
>
> -------------- Original message --------------
>
> > Hi,
> > Not MY 3dB rule; just a pure application of Shannon's theorem (see the link
> to
> > K1JT page and consult WSJT ver3 manual at the last page)
> > Please also read what I said about speed, bandwith efficiency, and test
> > conditions...
> > By the way the mode can also do 500, 250hz and 125Hz BW, yes it is slow,
> but it
> > is the price to pay for the power gain.
> > Bandwidth versus power versus speed... Not my theory, unfortunately!
> > At equal RTTY BW ~250Hz (8/250) yes, it is abt 3times slower than TTY, but
> also
> > 10dB more sensitive in a AWGN channel...still some 5dB benefit. Did not do
> the
> > tests yet, but I am sure it's gonna be far more significative under a
> > "CCIR-poor" channel (due to FEC). Did not test all modes combinations but I
> > guess it is also possible to use 250/4 for some 180LPM and get around -13dB
> in
> > an AWGN
> > channel...
> >
> > Please just look at the figures, and be open-minded! (and don't forget that
> > RTTY'ers are bandwidth wasters from PSK'ers point of view! - and what to
> say
> > about SSB'ers...;-)
> >
> > Patrick
> > Curious CW-operator
> >
> > PS: And I would be interested if you could tell me how to optimize the PSK
> > parameters to cope with a CCIR-poor channel... ;-) For RTTY under "flutter"
> > channel I actualy used MMTTY with "fluttered" preset...
> > And last but not least, you can easily reproduce the same tests on your
> own, and
> > publish your own conclusions - By the way please note that I did not emit
> any
> > opinion... just raw figures...
> >
> >
> >
> >
> > Re: [RTTY] Olivia's beauty...
> > from [tgstewart] [Permanent Link][Original]
> >
> > To: rtty@contesting.com
> > Subject: Re: [RTTY] Olivia's beauty...
> > From: tgstewart@pepco.com
> > Date: Mon, 14 Mar 2005 10:54:36 -0500
> > List-post:
> >
> > Yuk! 1khz bandwidth? Just what we need...>5 times less signals per khz
> > than RTTY or 20 times? PSK....and it's slow. I would also guess that you
> > didnt optimize the software settings for either RTTY or PSK for the
> > special conditions listed below. Lessee... 5 times the bandwidth and 1/2
> > the speed....by your 3db rule, Olivia should be at least 10 db better than
> > RTTY.
> >
> > Ty K3MM
> >
> >
> >
> >
> > f6irf@free.fr
> > Sent by: rtty-bounces@contesting.com
> > 03/14/2005 08:26 AM
> >
> > To
> > rtty@contesting.com
> > cc
> >
> > Subject
> > [RTTY] Olivia's beauty...
> >
> >
> >
> >
> >
> >
> > I just published a few figures concerning "Olivia" measured performances
> > versus a few other CGM's (PSK, RTTY, MFSK16. etc...)
> > http://groups.yahoo.com/group/oliviadata/message/87
> >
> > Patrick
> > F6IRF
> >
> >
> > PS if you have no idea of what Olivia is, here is where to start:
> > Olivia is a new MFSK mode designed by Pavel Jalocha SP9VRC.
> > http://homepage.sunrise.ch/mysunrise/jalocha/mfsk.html
> > Pavel's software is designed for Linux, but can run under Cygwin
> > Chris Watts VK3DNH has developped the windows interface.
> > A good tutorial is provided by N1SU http://n1su.us/olivia/
> >
> > The software provides limited features, just what is stricly required for
> > mode experimention.
> >
> >
> >
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