Satgen413 LEO NVNGsats v AMSATS by GM4IHJ (BID SGEN413) 22Feb97 (Satgen 376 refers ) Following their declared bid to take over much of the Radio Amateur VHF/UHF frequency spectrum, the Little Low Earth Orbit ,Non Voice Non Geostationary satellite interests have now added the American 219 to 225 MHz amateur band to their shopping list. At the same time they are continuing to push their desire to "share" these bands with other interests. An offer which has all the charm of being asked to bed down with an aggregation of alligators. Indeed what little they have said tends to suggest that their experience of these bands is nil, along with a similar lack of understanding of satellite operating features. For instance they propose that they could use different frequencies over different parts of the world to meet varying regional requirement for other services. Just how they propose to do this with satellites at altitudes above 700 kms, ie able to see Eastern USA and Western Europe simultaneously, is not explained. Of equal importance is their apparent assumption that these bands will support multiple user satellite operations at frequencies which are regularly disturbed by " communication disrupting " propagation features such as Sporadic E, Aurora, and FAIs. Just this last month European VHF and UHF sats operations were seriously disturbed for hours by intense Sporadic E on January 7th,18th,19th and 20th , and Aurora down to latitude 50N over Europe on February 8th and 9th. A situation which will be magnified many times in Northern Hemisphere summers for SpE, and over the next few years for Aurora, as Solar activity climbs to its cycle peak. But no one in the LEO commercial community appears to be listening. Every month or so someone is proposing yet a another new use for LEO sats. Latest of these is a proposal to use LEO weather sats which receiver GPS navigation satellite signals via long paths which see the GPSat through the earths atmosphere. Thereby measuring anomalies in the navigation signal and data, which will provide evidence of atmospheric conditions, for Weather forecasters. The GPS low microwave signal should be OK , but experience with Amsats suggests that VHF/UHF downlinks of LEO telemetry will be much less easy to read on a regular basis. One horrible thought that occurs with all this sudden LEO enthusiasm is " Who is it that has made LEO operation the flavour of the month"? Could it be Amsat ? What ever the answer to that is , the LEO interests are being very coy about what they actually intend . Their tactics have more of the "shotgun" than the "rifle" , in their go for everything, explain nothing approach. Their latest effort has suddenly added this bid for 219 to 225 MHz just before the deadline for the 4th March FCC consideration meeting. Fortunately ARRL and Amsat NA have presented our very strong case for them to keep off amateur frequencies (RSGB appears to think American satellites only affect Americans, and , have indicated they will wait and see, rather than submit a strong report backing ARRL). IHJ submitted a paper to the FCC in June 96. Meanwhile still no news of Orbcoms attempts to duplicate Uosat store and forward birds - only 2 sats are up the remaining 24 are still awaited. Is it possible there is a lesson here for the LEO interests ?