[OZAPRS] PCSAT alive and well

[Robert Bruninga]

> What about a digi that splits frequencies ? 
> Say listens to 145.825 MHz for SGATE, but swaps and TX on 
> 145.175 MHz, then falls back to 145.825 MHz ready to RX again.

Yes, but when that packet arrives at FINDU which is looking for
PCSAT-1* it wont find it and so that packet will not be
accumulated on the PCSAT-1 web page.

And it is just such an arrangement in a forgotten radio, that
could accidentally be set to simplex instead of split operation
and end up Txing back on the uplink.  All it takes is one radio
on the whole continent to do this and that doubles the QRM on
the uplink.

I am not saying "don't do it", but in general, I don't see the
value added compared to the risk added.
But then if it helps show people satellite activity, and is
carefully set up, then it is a possibility, but then the pakets
only go LOCALLY.  This then suggests that dozens of digis should
be set up to do it, to cover any reasonable area, but then this
multiplies the risk that one of them will be set up wrong and
ruin it for everyone...

And 2 radios wont help because even if one is listening on
145.825 and the other Txing on 145.175, it will still block the
other receiver during the packet digipeat.

Bob

> Mind you, while it is TX on 145.175 MHz, it can not hear on 
> 145.827 MHz.
> 
> Unless you use two radios ....
> 
> -----------------------------------------
> Andrew Rich
> Amateur radio callsign VK4TEC
> email: vk4tec at tech-software.net
<mailto:vk4tec at tech-software.net>
> web: http://www.tech-software.net
> Brisbane AUSTRALIA
> 
> 
> 
> -----Original Message-----
> From: Robert Bruninga [mailto:bruninga at usna.edu]
> Sent: Friday, 5 January 2007 10:50 AM
> To: vk4tec at tech-software.net; 'VK / ZL APRS Users'
> Subject: RE: [OZAPRS] PCSAT alive and well
> 
> 
> > So what benefit would be gained from placing a digi on
> > 145.827 MHz and set the alias to SGATE ?
> 
> None, it would QRM the uplink for every pacekt heard.
> 
> > Could try driving to a hill first, with the house on 145.825
> > and the car as a digi.
> 
> I really don't like any terrestrial digipeating via SGATE,
> because
> 1) There is too much potential for  human error to jam the
> uplink
> 2) Packets that get digipeated on the ground do not show
> PCSAT-1* in them and so those packets do not get picked up by
> FINDU.
> 
> It just messes everythign up.  Any mobile should be able to
hear
> PCSAT-1 direct, even better than a home station due to less
coax
> loss, so I prefer people just listen to the satellite if they
> want to hear it.
> 
> Bob, WB4APR
> 
> > -----------------------------------------
> > Andrew Rich
> > Amateur radio callsign VK4TEC
> > email: vk4tec at tech-software.net
> <mailto:vk4tec at tech-software.net>
> > web: http://www.tech-software.net
> > Brisbane AUSTRALIA
> >
> >
> >
> > -----Original Message-----
> > From: Robert Bruninga [mailto:bruninga at usna.edu]
> > Sent: Friday, 5 January 2007 12:36 AM
> > To: vk4tec at tech-software.net; 'VK / ZL APRS Users'
> > Subject: RE: [OZAPRS] PCSAT alive and well
> >
> >
> > > Subject: Re: [OZAPRS] PCSAT alive and well
> > > What sort of antenna u running ?
> > > Bob tells me RAFT and ANDE require beams ?
> >
> > Yes, if you want to hear down to the horizon.  But a whip
will
> > hear a few packets a day at the center of the two best
passes
> of
> > the day.  On an oerhead pass, the satellites are 6 to 10 dB
> > closer.  Hence, a whip will do nicely.  But the satellites
are
> > only "overhead" like 10% of the total times they are in
view.
> >
> > Hence, use beams if you want longer pass times.
> >
> > Use a whip for an unattended SATgate (which combines it's
few
> > packets with a few packets from other such whip ground
> stations
> > for good accumulation by FINDU)...  That's why we can use
more
> > satgates especially if they are widely separated and in very
> > remote locations like Islands and other places besides the
> USA,
> > Canada, Europe and the east coast of Australia and NZ.
> > Bob, WB4APR
> >
> > Bob
> > >
> > > Cheers
> > >
> > > -----------------------------------------
> > > Andrew Rich
> > > Amateur radio callsign VK4TEC
> > > email: vk4tec at tech-software.net
> > <mailto:vk4tec at tech-software.net>
> > > web: http://www.tech-software.net
> > > Brisbane AUSTRALIA
> > >
> > >
> > >
> > > -----Original Message-----
> > > From: Scott & Clare Evans
[mailto:clareandscott at bigpond.com]
> > > Sent: Thursday, 4 January 2007 7:10 PM
> > > To: ozaprs at aprs.net.au
> > > Subject: Re: [OZAPRS] PCSAT alive and well
> > >
> > >
> > > I'm Rx only here in southern VK7 (SGATE)
> > >
> > > Hearing NO-44, RAFT & COMAND-1 so far...
> > >
> > > 73 de VK7HSE Scott Evans
> > >
> > > _______________________________________________
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> > >
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> >
> >
> >
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> 
> 
> 
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