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There are 20 different meanings of Oscar.
 
Acronym
4 products, approx. 20 pages
OSCAR is an acronym for Orbital Satellite Carrying Amateur Radio. SuitSat
1 product, approx. 1 pages
SuitSat, an obsolete Russian space suit with a transmitter aboard, is officially known as OSCAR 54. In a twist of fate, "Oscar" was the name given to an obsolete space suit by its young owner in the book "Have Space Suit, Will Travel," by Robert A Heinlein. This book was originally published a year after the launch of the first artificial satellite (Sputnik). The first amateur satellite simply named OSCAR-1 , was launched on December 12, 1961, barely four years after the launch of Russia's first satellite, Sputnik. OSCAR-1 was the very first satellite to be ejected as a secondary payload and subsequently enter a separate orbit. Despite being in orbit only 22 days OSCAR-1 was an immediate success with over 570 amateur radio operators in 28 countries forwarding observations to Project OSCAR. Throughout the years OSCAR satellites have helped make significant breakthroughs in the science of satellite communications. A few advancements include the launch of the very first satellite voice transponders and the development of highly advanced digital "store-and-forward" messaging transponder techniques. To-date over 70 OSCAR's have been launched with more to be launched in the near future. Due to the high orbital speed of OSCAR satellites, the uplink and downlink frequencies will vary during the course of a satellite pass. This phenomenon is known as the doppler effect. While the satellite is moving towards the ground station, the downlink frequency will appear to be higher than normal and therefore, the receiver frequency at the ground station must be adjusted higher in order to continue receiving the satellite. The satellite in turn, will be receiving the uplink signal at a higher frequency than normal so the ground station's transmitted uplink frequency must be lower in order to be received by the satellite. After the satellite passes overhead and begins to move away, this process reverses itself. The downlink frequency will appear lower and the uplink frequency will need to be adjusted higher. The following mathematical formulas relate the doppler shift to the velocity of the satellite. Due to the complexity of finding the relative velocity of the satellite and the speed with which these corrections must be made, these calculations are normally accomplished using satellite tracking software. Many modern transceivers include a computer interface that allows for automatic doppler correction. Manual doppler correction is possible, however it is difficult to remain exactly on frequency. FM is more tolerant of doppler shift than SSB and therefore much easier to tune manually. Currently 21 countries have launched an OSCAR satellite. These countries, in chronological order by date of launch, include: The United Kingdom, The United States of America, Spain, Australia, Japan, Brazil, Argentina, Russia, France, Portugal, Korea, Italy, Mexico, Israel, Thailand, South Africa, Malaysia, Saudi Arabia, Germany, India, & Colombia. 
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