4 Dec 1999
Satellite Buffs, and Digital Mobile operators,

Here is a quick summary of the APRS QSO party conducted 3/4 Dec on the three
1200 Baud PACSATS.  During the 5 Saturday passes over 400 UI packets were 
exchanged with at least 11 stations seen (even while 6 stations were logged
on and downloading PACSAT Protocol).  All downlink  packets were also
linked into the worldwide APRServe internet system.  During some warm up
passes on Friday, 287 packets were exchanged.

One station, KA2UPW was using only a sound card on his PC to generate the
necessary MANCHESTER uplink.  Others were using APRSdos, APRSplus or
WinAPRS and some with just terminal software.  The sound card method
makes it possible for anyone with a laptop and a 2m radio to uplink while
mobile.

With 3 satellites, ALL with uplinks on 145.90, (I was running only 20 
watts into a mobile WHIP antenna!) there is great potential
for providing mobile APRS POSITION/STATUS reporting for travelers via
satellite.  For example, the orbits of these birds gives the following
coverage pattern everywhere (local sun time):

DAY:  0930-1230 About 7 or 8 passes lasting 8-15 minutes each
NITE: 1930-0030 About 7 or 8 passes lasting 8-15 minutes each

Now all we need is someone to write the 1200 baud PSK downlink modem in
software for a sound card, and then these 9 year old satellites will be
VERY USABLE again...

APRS STATIONS:  WB4APR, KB2WQM, N8DEU, KA2UPW, K5QXJ, N5ZNL, W4HFZ, WS4Z
PACSAT USERS:   W4MO,VE3FRH,VE2KAD,N8ULD,K0RZ,TG9IKE,VE3BCG,WE1U,N0ALJ

NOTES:  The throughput of these 1200 baud satellites can be an order of
magnitude greater than terrestrial systems for several reasons:

   1) Each has 4 simultaneous receivers.  Thus even with only a 25%
      success rate on each uplink, the downlink can be kept full
   2) Since everyone hears the satelite direct, there need be only
      ONE digipeater hop, instead of the 3 or more duplications on
      the ground
   3) Since the satelite is crossband full duplex, the downlink is
      on 100% of the time instead of the maximum 50% for a simplex digi.

Thus, the birds could handle many hundreds of stations per pass per
satellite!  Right now, LO19 and IO26 are 100% dedicated to UI or APRS
digipeating.  AO16 is shared, since its PACSAT BBS is still functional and
usually has a few users on the weekends...  With 9 years in space, I find
that the birds may have shifted somewhat from their published uplink
frequencies.  I found these freqs best for me.  THese are just one each
of the 4 channels availaable on these birds.

AO16  145.910 start, 145.915 finish
LO19  145.890 start, 145.895 finish
IO26  145.880 start, 145.885 finish

I will post the results on our TRAKNET web page so you can browse the
captured files if you are interested:

    http://web.usna.nadn.mil/~bruninga/traknet.html

de WB4APR, Bob