[aprssig] What is this packet data

[Robert Bruninga]

> Is this an ISS in range packet system ?
>
>20/09/05 07:29:52 ISS_>APRS,qAo,AJ3U-5::N3ZLL-14 :%[54]
>20/09/05 07:29:54 ISS_>APRS,qAo,AJ3U-5::KB2M-9   :%[54]
>20/09/05 07:29:55 ISS_>APRS,qAo,AJ3U-5::KG4NVB-9 :%[54]  

Yes, Those are messages transmitted to all local APRS
users whenever the ISS (or any other FM satellite
workable from the mobile) are in view.  Normally a once
-per-minute object is posted so your mobile will display
the satellite name, azimuth and range.  

THe specific packets above will cause the D700 to speak
the elevation angle of the ISS to those stations who
subscribe to this feature.  The radio will say "ISS LOW"
or "ISS HIGH" depending on the elevation  angle.

THus the driver does not even need to lkk at his
D700 display to know that the ISS is in view and
about how high it is...  Then all you have to do
is look in the D700 station list and you will not only
see the satellite, but also its frequencies and
present doppler.  Everything you need to work
it right then and there.

This data is posted on APRS by the APRSdata.exe
program that only one person per metro area
needs to run, to keep ALL mobiles abrest of any
satellites in view.    Also, once evey 10 minutes
this program updates your D700 or D7 with 
a schedule of all future passes to expect in the
next 80 minutes.   Everything you need whild
commuting to work any satellites that might happen
by...

read about it about 50% down this page:

http://www.ew.usna.edu/~bruninga/astars.html

de WB4APR, Bob