... This program will this notify the users of upcoming passes via APRS messaging.
Better to use OBJECTS so that all of the following shows up on the front panel of the radio:
Satellite Name Direction, and Range Uplink Freq (and doppler) Downlink Freq and Doppler Elevation (HIGH or LOW). Direction of movement
I would suggest you look at the digi_ned source code. It works great and does everything you want. [that is, sending out all the Satellite Objects info on APRS shown above]
There was a change on the last update where he replace the display of azimuth/elevation to HIGH(over 30 degrees) and LOW (Below 30 degrees). That change actually works very well when driving down the road.
And if it is like the original APRSdata.EXE, those are encoded with a leading % sign so that the D700 radio with a voice chip will actually SPEAK "HIGH" and "LOW" so you never even have to look at the radio.
For example, you are just driving down the road, and your D700 (with voice chip)announces: "AO-51 435.300 -5 KHz 145.85 +1 KHz HIGH"
And if you look at the radio, it displays all the other info above.
This is just part of the local INFO that can be pushed to the front panel of the APRS radios as a service to the mobile operator. I'm glad you are taking on this challenge, because, no one uses the original APRSdata.EXE that did this, there are very few DIGI-NED's on the air doing it, and so we need a Windows version that each local area can run to serve their users.
Bob, WB4APR