Yes, MMTTY supports it ... go to the "decode" tab, select 8 bit,
2 stop bits and your choice or parity. as well as the baud rate.
It's probably wise to find an optimized BPF on the "demodulator"
tab as well - particularly if you are using a higher data rate.
The smart thing to do would be to save both the new BPF parameters
and the 8 bit settings in a new "parameter" file so you can switch
settings "at will."
Note 60 baud 8N1 (ASCII) would have the same throughput as 45.45
baud 5N1.5 (ITA2/Baudot). For 8N2, the baud rate for comparable
throughput is 66.66. That makes 75 8N2 an interesting alternative
to 45.45 5N1.5 ... but with about a 25% increase in bandwidth
(and 1 dB drop in s/n due to the wider filter).
Given the last of LTRS/FIGS overhead and the slightly higher
baud rate, 75 8N2 would probably represent a 20% increase in
throughput. I leave it to Chen or someone else with access to
the formulae to calculate the loss of BER from the higher data
rate.
73,
... Joe, W4TV
> -----Original Message-----
> From: rtty-bounces@contesting.com
> [mailto:rtty-bounces@contesting.com] On Behalf Of Jerry Flanders
> Sent: Thursday, January 28, 2010 6:34 PM
> To: roger@g3ldi.co.uk; rtty contesting rttycontesting
> Cc: bartg@bartg.org.uk
> Subject: Re: [RTTY] High Speed RTTY again
>
>
> Sure would be nice to get rid of the two-case problems inherent in
> Baudot. Is there any support for 110 baud ASCII in MMTTY or other
> widely used digital programs?
>
> Jerry W4UK
>
> At 05:25 PM 1/28/2010, Roger Cooke wrote:
> >Hi.
> >
> > Judging by the amount of emails flying about there does
> seem to be some
> >interest in 75 Baud RTTY at last! I have had several QSOs
> at that speed
> >both on 80 metres and 20 metres with total success. In fact I have
> >tried up to 110 Baud. Using 170Hz shift within a 250Hz filter width
> >errors start creeping in at 110 Bauds and even at 100 Bauds, but 75
> >seems a good standard to aim for. It would increase Q rate in both
> >contests and DX-pedition pile-ups, but it certainly is
> stressful on the
> >typing!
> > I usually answer points as the other station is
> transmitting anyway
> >and then sending at full speed it sure does rattle along. I will be
> >calling CQ on 20 metres
> >on Friday at around 1400z at 75 Bauds if anybody wants a QSO.
> >
> > John, GW4SKA certainly is giving it some thought now for a BARTG
> >contest at that speed, possibly a short one, but as he says,
> although
> >membership of BARTG is free and we would like as many as we can get,
> >staging the contests does cost, with the certificates and
> plaques and
> >things. Small donations add up so please consider making
> just a token
> >donation when joining. It will all help
> >sponsor the contests, plus BARTG also sponsors DX-peditions
> too. If you
> >would like to sponsor a plaque too, that would be really
> nice! Perhaps all
> >RTTY contests will move over to 75 Bauds. :-)
> >
> > The next main BARTG contest is the Spring, in March. Don't forget
> >the GB50ATG event that is on-going too. There are some nice
> >certificates and plaques available for that. GB50ATG finishes at the
> >end of July. Take a look on the BARTG web site, and see if it floats
> >your boat, cocas your cola, bakes your cake, or diddles your Baud!!!
> >
> >www.bartg.org.uk
> >
> > Send some feedback. Hey, if you DO join, why not send us
> some pictures
> >of your station/antennas etc., for the Gallery. You can
> even see the
> >mug-shots
> >of the committee on there if you can stand it!
> >
> >See you on the green keys on 75 Bauds Fri PM.
> >
> >73 de Roger, G3LDI, Chairman, BARTG
> >_______________________________________________
> >RTTY mailing list
> >RTTY@contesting.com http://lists.contesting.com/mailman/listinfo/rtty
>
> _______________________________________________
> RTTY mailing list
> RTTY@contesting.com http://lists.contesting.com/mailman/listinfo/rtty
_______________________________________________
RTTY mailing list
RTTY@contesting.com
http://lists.contesting.com/mailman/listinfo/rtty
|