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I left a link to the awesome Dr. Dish page. Here's a taste of what some of these guys like to play with.

Military satellites

The military obviously protects its data from a curious public and other countries but even here people can get sloppy. During the Gulf war anyone that was sufficiently interested could occasionally get quite a good idea of the situation as uncoded radio chatter was often to be heard on the US-FLTSATCOM satellites. As with the weather satellites there are two distinct groups of satellites; geostationary and orbital.

The American system is based upon the FLTSATCOM series and the DSCS satellites. they additionally use the UHF band of the MAREC and INMARSATs (200-400 MHz). The UK puts its trust in its SKYNET satellites and Russians have probably already lost track of their military and spy satellites. The most well known series is the COSMOS series. These satellites can carry out just about every function you can think of. They can be configured as amateur radio, weather, scientific or military satellites. A complete overview of the area of application and technical data can be found in the SATELLITE’S ENCYCLOPEDIA by Jean-Philippe Donnio. This, probably the most reliable reference work, is available on disk.

The complexity of receiving and decoding transmissions from these satellites is enourmous. From time to time decoding is not possible. In spite of all this, these satellites can be a valuable source of information in times of crisis as a considerable proportion of traffic is voice. Video signals can’t be received but faxes pose no problem and thus programs such as CODE-3 with appropriate decoder are adequate for some data. The requisite receivers are expensive. The frequency range from 100 to over 2000 MHz is recommended and that doesn’t come cheap. Suitable units cost between 2000 and 9000 Marks (or £ 850-4000). When it comes to the antennas compromises can be made. A good Discone antenna with integrated amplifier is adequate for the reception of FLTSATCOM (200-400 MHz). Better however is the cruciform YAGI antenna for this frequency range. FLTSATCOM can be easily picked up in Europe. A Discone with a band amplifier gave good results in Holland. A good LOG periodic antenna is fine for the L- and S-bands.

In addition to their numerous COSMOS satellites the Russians also operate a large number of geostationary RADUGA satellites. A glance at a good satellite list will assist in locating these. The purpose of these most versatile satellites is to supply TV images, enable normal telecommunications and to serve the military, who use the lower C-band (below 3.65 GHz). Worth searching out is RADUGA 29 (drifting) at approximately 12.3° East. Simply switch from the Hot Bird position to the C-band and use the black carriers to target the satellite. FDM and SCPC can be found here. Outside of the UHF, L, S and C-band the military is obviously increasingy moving into the X-band. Rejected military equipment for this band is available from surplus dealers but the prices are usually out of the reach of amateurs. It’s a great source for poor, small countries to stock up their military electronics.