Satgen 120 A Satellite Launch Review by GM4IHJ 15 July 91 Of the 55 or so satellites launched in a recnt 6 month period :- GEOSTATIONARY 13 have gone to this orbit 5 Soviet and 8 others.Downlink bands include:- a. L band and C band for land air mobile comms . The 1530 to 1540MHz is easily covered on many scanners. b. C band down for TV and data 2560 to 4200 MHz c. Data channels 5125 to 7750 MHz d. Ku band TV and data 10950 to 12500 MHz MOLNIYA HIGH ELLIPTICAL ORBITERS 4 Soviet sats using C band downlinks in the band 3400 to 4100 MHz ( mostly at high elevation 35 degs over Tomsk in USSR or on other half of the day, 60deg over Hudsons Bay ,seen from UK) GPS and GLOSNASS High circular orbit navsats 2 US and 3 Soviet new ones. US on 1575.42 and Soviet in band around 1603.5 MHz LEO Navsats 3 Soviets launched downlinks simultaneous on 140MHz and 400MHz LEO MILITARY 15 Soviet milcomsats were launched. One follow my leader group of 6 and another group of 8. There was also a lone miltest sat. PHOTO RECON there were 8 Soviet launches in this category. Typical downlinks are 232MHz, 240MHz and 331.5MHz. Orbit period 89 min approx ELINT Electronic Listening . There were 3 Soviet launches in this category They use 153 and 204MHz approx downlinks simultaneously WEFAX Weather picture satellites There were 3 launches . 1 Chinese , one Russian and one US Dep of Defence. The 1st 2 are on 137MHz approx. SCIENCE Two Chinese balloon satellites were released with their weather sat launch, and Ulysees the European Solar Polar Mission launched by shuttle for a sling shot manoeuvre round Jupiter before circling the Sun's poles. Subject to Government regs in each country, all these sats are trackable apart from some of the Geosats which stay below your horizon permanently Recent puzzles are the Soviet multiple launch low earth orbit ( circa 1400 kms height 114 min period ) military comsats. At the last count more than 50 of these birds were in orbit ,some in groups of 8, some in groups of 6. Roughly half have 82.58deg inclination, the others have 74deg inclination. An interesting recent saga has been the drift off station of European test TV sat Olympus. It may be that an incorrect uplink signal put it out of control for good. A very sad loss. But not as bad as the 4 succesive Japanese Yuri Direct Bcast TV sats, which have all succumbed to either power failure, solar cell problems or launch accidents. Last but not least " Be careful when you read NASA Keps ". Some satellites are " Breeding" .At some interval after launch one recent shuttle mission released at least 4 separate packages all transmitting, and one US milsat suddenly became 4, when it deliberately released 3 new military packages. You may see new additions in NASA Keps Eg 1990-103A is supposed to be a Navstar, but some of the NASA keps for it are very odd, addition 103B looks like a low altitude Ferret probe or launch debris but 103C is also in a very odd orbit . So careful examination of the Keps can produce a mystery or two. 73 de John GM4IHJ @ GB7SAN