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RE: SUNSAT PAROT Mode thought...



> The problem is that with only a 10 second 
> RECORD-PLAYBACK-in-the-blind 
> cycle, it is almost useless for voice which takes about  5 seconds for
> each transmission.  With 100's of stations trying, no amount of
> arguing over operators and procedures will change this.

Obviously, there are problems in the high density areas.

> 0.3 second burst each cycle, then as many as 30 stations could be
> successful per cycle.  This is easy to do with a UI packet at 
> 9600 baud.
> Anyone with a 9600 baud TNC could participate and anyone with 
> THD7(g) HT 
> or TMD700 mobile rig can do it from the front panel.

But will it work?  Has anyone thrown in a 9600 bps packet, to see what
happens? (the issue being the suitability of the audio record/playback
system for 9600).  I imagine 1200 would be no drama at all.
 
> Many will argue that PAROT mode is not for packet.  I agree.  
> But I dont
> see any way that VOICE can work except out in the middle of 
> the atlantic
> or Pacific or Antarctica, or of course for those that run 1000 watts.

Well, when you get more than a couple of dozen stations competing for the
transponder, you have a problem (less, if some of the stations aren't
following good practice).

> experiment, consider that for each person that tries ONE 9600 
> baud packet
> per cycle, that is one less person that you are competing with for the
> other 9.5 seconds.  Therefore it coiuld be considered in your best
> interest also...

Well, I think it's worth a shot.  I've also noticed that the last second or
two of each 10 second window is least likely to contain any other signal, so
a packet could fit in easily there.

> Actually 1200 baud would work even 7 dB better, though the 
> packet will be
> about 0.5 second instead of 0.3.   But the sound of a 1200 baud BRAAAP
> would certainly not go over well! <grin>

However, I would like to see a 1200 bps mode both ways to a satellite.  A
simplex digi on 2m could be interesting to play with for APRS purposes.  No
tune, and compatible with un modified radios, which might be to advantage
for people travelling in remote areas (e.g. the Australian outback), with 2
way performance suitable for mobile and portable stations.
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