Satgen 610 AO40 Simple HB Sware by GM4IHJ (BID SGEN610) 2000-12-02 With AO40 up, even Scottish pessimists have to start putting things together. Hardware is no problem. But the old AO10 and AO13 tracking software looks a trifle dated. So first thing up was a simple tracking program. AO10 experience suggested reports every 10 minutes, would be the best compromise. So the standard Molniya algorithms in use since 1981 were quite adequate. Producing a table of Azimuth, Elevation, Subsat Latitude, Subsat Longitude and , Mean Anomaly . Which are printed out for 10 minute intervals over 2.5 hours. Later on print out of doppler shift may be added, once the operating bands in use at this station are clear. Graphics in any sat tracking program are a highly personal choice. With Leo sats , local area maps are useful. But with high flying elliptical orbiters the ordinary Mercator projection of the whole world is more than adequate. On it the satellite position is shown for every 10 minute record in the table. This is untidy at Apogee where all the positions crowd together, but at perigee as the satellite zips across half the earth , it is invaluable. Though until the perigee gets a little higher and or the inclination increases, perigee will not be visible at IHJ. Of perhaps more importance, the graphic display should also show the extent of the satellite footprint on the earth. Here a compromise is necessary. To show the footprint as it changes every 10 minutes is hardly necessary except at perigee. So the footprint is printed at the time corresponding to the data in the last line of the AZ El table. Much more conjectural , but useful to get a general idea of who is experiencing unsociable hours ("insomniacs only" QSOs, possible). Is display on the Mercator of the position of the Sun , and the extent of the solar terminator line at the earths surface. Again this is a compromise whereby the terminator shown corresponds to the time of the last line in the AZ El table. Noting that the Sun moves 37.5 degrees in 2.5 hours , this may be an assumption too far for purists , but it will suffice for now until much more AO40 operating experience is obtained. May be if AO40 lasts as long as AO10, this will change. For PSK download the choice is the readily available IZ8BLY software, ( details at http://iz8bly.sysonline.it/. ) It is sensitive to audio level and does produce a few errors from time to time ( errors which have more to do with the PSK format than the software). Once set up it works well and you can download telemetry for later decode ( eg TLMDEC.EXE translates P3D.tlm ).