[amsat-bb] Re: volunteering (Mobile Satellite Predictor)

Robert Bruninga bruninga at usna.edu
Tue Oct 20 09:56:08 PDT 2009

> I would like to volunteer to help out 
> in whatever capacity I can. I run my
> own web server built by myself and a 
> few websites.

Seeing your message, caused me to stop and think, what is the
next thing I think might be valuable to help the general amateur
radio operators to better operate the satellites?  Again, this
might not be at all what you are interested in, but let me have
a go at defining a nice project for someone in case this fits
anyone's talents.

PROBLEM:  To play satellites, you need to have a tracking
program and to WATCH it all the time or do PLANNING to know when
to go play satellites.  Actually, this is so... Past decade.

OBJECTIVE:  What we need is a "service" that continuously feeds
SAT-IN-VIEW information to everyone in the field right there on
their radio front panel, whenever any AMSAT is in view.  This
way, you can be mobile, or hiking, or anywhere on the planet,
and right their even without ASKING, the information will be
PUSHED to you.

SOLUTION:  Actually, this capability has existed since about
1997 on the APRS channel, but it only works where a LOCAL
individual runs either APRSdata or DIGI_NED in the local region,
and maintains it.  In this case, mobiles, or anyone monitoring
the national APRS channel will receive this INSTANT information
not only showing any SAT in view, but also its AZIMUTH,
ELEVATION and FREQUENCY of both the uplink and downlink AND

You can see examples of this system on
http://www.aprs.org/localinfo.html .  Move your slider about 90%
down the page and look for the paragraph LOCAL SATELLITE ALERTS.

This way you don't need any PC, or anything.  But if you are
mobile and if a satellite comes above the horizon in your area,
and you monitor APRS on your APRS mobile radio, then you will be
able to work the satellite (also mobile, since we only output
the satellites that are easy to work from a mobile)...  The info
on the satellite is updated once each minute when it is above
the horizon.

Also, once each TEN minutes a SCHEDULE of any satellites coming
up in the next 80 minutes is transmitted to the DX LIST inside
your radio, so you can also check for any future passes.

PROJECT:  Rather than having to have 1000 volunteers all over
the world, one in the footprint of every APRS local area have to
operate and maintain one of these programs (which is why most
people never see these alerts), it would be nice if there was
just ONE central server that fed this data everywhere.  Then
only one person would have to update the server when new
satellites were launched and once every week or so to download
new TLE element sets.

ISSUES:  In one sense this would be a great step forward, in
centralizing the generation of this data.  But the problem is,
that it still will not go from the APRS-internet stream back to
local RF in each local area, unless a local Igate operator adds
the "server" to his gate-to-RF list.  But at least that is much
simpler than having to maintain a program.
Local AMSAT mobiles who want this feed, just ask their local
Igate operator to add the server, and from then on, whenever
mobile, they will see these alerts. 

RESULT:  Every mobile everywhere that is in view of a satellite,
even without any prior planning, will be alerted to a satellite
in view, its direction and elevation, its frequency and its
Doppler, right there on the front panel of his APRS radio.

See the web page for what these displays look like on an APRS

Bob, WB4APR 

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