OSCAR is an acronym for Orbiting Satellite Carrying Amateur Radio. OSCAR series amateur radio satellites use amateur radio frequency allocations to facilitate communication between amateur radio stations. AMSAT was started by a group of Amateur Radio Operators most of which were working at or associated with Goddard Space Center north of Washington DC.
These satellites can be used for free by licensed amateur radio operators for voice (FM, SSB) and data communications (AX.25, packet radio, APRS). Currently over 5 fully operational satellites in orbit act as repeaters, linear transponders or store and forward digital relays.
The beginning of this project was very humble. The satellite had to be built in a very specific shape and weight the place of one of the weights used to balance the payload in the rocket stage. By NASA specification, it could not contain any propulsion system so as not to pose danger to the expensive payload the Thor Agena launch vehicle was carrying.
Throughout the years OSCAR satellites have helped make breakthroughs in the science of satellite communications. A few advancements include the launch of the first satellite voice transponder (OSCAR 3) and the development of highly advanced digital "store-and-forward" messaging transponder techniques. To date, over 70 OSCARs have been launched.
The first amateur satellite, simply named OSCAR 1, was launched on December 12, 1961, barely four years after the launch of world's first satellite, Sputnik I. OSCAR 1 was the first satellite to be ejected as a secondary payload (Discoverer 36) and subsequently enter a separate orbit. Despite being in orbit for only 22 days OSCAR 1 was an immediate success with over 570 amateur radio operators in 28 countries forwarding observations to Project OSCAR.
Most of the components for OSCAR 10 were "of the shelf" and tested by group members. Jan King lead the project. Solar cells were bought in batches of 10 or 20 from Radio Shack & tested for efficiency by group members (A. Sergio Torloni then a senior in high school) the most efficient cells were kept for the project, the rest were returned to RadioShack. Once ready, OSCAR 10 was mounted aboard a private plane & flown on a couple of occasions to evaluate its performance & reliability. Special QSL cards were issued to those who participated in the airplane based flights. Once it was found to be operative & reliable, the satellite was shipped to Kennedy Space Center where it was mounted in the 3rd stage of the launch vehicle.
OSCAR satellite communications
- Historically OSCAR uplink (transmit to) and downlink (receive from) frequencies were designated using single letter codes.
- New uplink and downlink designations use sets of paired letters following the structure X/Y where X is the uplink band and Y is the downlink band.
Due to the high orbital speed of the 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.
|=||doppler corrected downlink frequency|
|=||doppler corrected uplink frequency|
|=||velocity of the satellite relative to ground station in m/s.
Positive when moving towards, negative when moving away.
|=||the speed of light in a vacuum ( m/s).|
|Change in frequency||Downlink Correction||Uplink Correction|
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 effect correction. Manual frequency-shift correction is possible, but it is difficult to remain precisely near the frequency. Frequency modulation is more tolerant of doppler shifts than single-sideband, and therefore FM is much easier to tune manually.
Satellites previously launched
The names of the satellites below are sorted in chronological order by launch date, ascending. The status column denotes the current operational status of the satellite. Green signifies that the satellite is currently operational, orange indicates that the satellite is partially operational or failing. Red indicates that the satellite is non operational and black indicates that the satellite has re-entered the Earth's atmosphere. The country listing denotes the country that constructed the satellite and not the launching country.
Name (a.k.a.) Status Launched Country OSCAR (OSCAR 1) Decayed 1961-12-12 USA OSCAR II (OSCAR 2) Decayed 1962-06-02 USA OSCAR III (OSCAR 3, EGRS-3) Non-Operational 1965-03-09 USA OSCAR IV (OSCAR 4) Decayed 1965-12-21 USA Australis-OSCAR 5 (OSCAR 5, AO-5, AO-A) Non-Operational 1970-01-23 Australia AMSAT-OSCAR 6 (OSCAR 6, AO-6, AO-C, P2A) Non-Operational 1972-10-15 USA AMSAT-OSCAR 7 (OSCAR 7, AO-7, AO-B, P2B) Semi-Operational 1974-11-15 USA AMSAT-OSCAR 8 (OSCAR 8, AO-8, AO-D, P2D) Non-Operational 1978-03-05 USA/Canada/Germany/Japan Radio Sputnik 1 (RadioSkaf-1, RS-1) Non-Operational 1978-10-26 USSR Radio Sputnik 2 (RadioSkaf-2, RS-2) Non-Operational 1978-10-26 USSR UoSat-OSCAR 9 (UOSAT 1, UO-9) Decayed 1981-10-06 UK Radio Sputniks RS3 through RS8 Non-Operational 1981-12-17 USSR AMSAT-OSCAR 10 (Phase 3B, AO-10, P3B) Non-Operational 1983-06-16 USA/Germany UoSat-OSCAR 11 (UoSat-2, UO-11, UoSAT-B) Semi-Operational 1984-03-01 UK Fuji-OSCAR 12 (JAS 1, FO-12) Non-Operational 1986-08-12 Japan Radio Sputnik 10/11 (RadioSkaf-10/11, RS-10/11, COSMOS 1861) Non-Operational 1987-06-23 USSR AMSAT-OSCAR 13 (Phase 3C, AO-13, P3C) Decayed 1988-06-15 Germany UOSAT-OSCAR 14 (UoSAT-3, UO-14 UoSAT-D) Non-Operational 1990-01-22 UK UOSAT-OSCAR 15 (UoSAT-4, UO-15, UoSAT-E) Non-Operational 1990-01-22 UK AMSAT-OSCAR 16 (Pacsat, AO-16, Microsat-1) Semi-Operational 1990-01-22 USA Dove-OSCAR 17 (Dove, DO-17, Microsat-2) Non-Operational 1990-01-22 Brazil Weber-OSCAR 18 (WeberSAT, WO-18, Microsat-3) Non-Operational 1990-01-22 USA LUSAT-OSCAR 19 (LUSAT, LO-19, Microsat-4) Non-Operational 1990-01-22 Argentina Fuji-OSCAR 20 (JAS 1B, FO-20, Fuji-1B) Non-Operational 1990-02-07 Japan AMSAT-OSCAR 21 (RS-14, AO-21, Informator-1) Non-Operational 1991-01-29 Russia Radio Sputnik 12/13 (RadioSkaf-12/13, RS-12/13, COSMOS 2123) Non-Operational 1991-02-05 Russia UoSat-OSCAR 22 (UOSAT 5, UO-22 UoSAT-F) Non-Operational 1991-07-17 UK KitSAT-OSCAR 23 (KITSAT 1, KO-23, Uribyol-1) Non-Operational 1992-08-10 Korea Arsene-OSCAR 24 (Arsene, AO-24) Non-Operational 1993-05-12 France KitSAT-OSCAR 25 (KITSAT B, KO-25, Kitsat-2, Uribyol-2) Non-Operational 1993-09-26 Korea Italy-OSCAR 26 (ITAMSAT, IO-26) Non-Operational 1993-09-26 Italy AMRAD-OSCAR 27 (EYESAT-1, AO-27) Non-Operational 1993-09-26 USA POSAT-OSCAR 28 (POSAT, PO-28, Posat-1) Non-Operational 1993-09-26 Portugal Radio Sputnik 15 (RadioSkaf-15, RS-15, Radio-ROSTO) Semi-Operational 1994-12-26 Russia Fuji-OSCAR 29 (JAS 2, FO-29, Fuji-2) Semi-Operational 1996-08-17 Japan Mexico-OSCAR 30 (UNAMSAT-2, MO-30, Unamsat-B, Kosmos-2334) Non-Operational 1996-09-05 Mexico/Russia Thai-Microsatellite-OSCAR 31 (TMSAT-1, TO-31) Non-Operational 1998-07-10 Thailand Gurwin-OSCAR 32 (GO-32, Gurwin-1b, Techsat-1b) Non-Operational 1998-07-10 Israel SEDSat-OSCAR 33 (SEDSat, SO-33, SEDsat-1) Semi-Operational 1998-10-24 USA Pansat-OSCAR 34 (PAN SAT, PO-34) Non-Operational 1998-10-29 USA ARISS (ARISS) Operational International Sunsat-OSCAR 35 (SUNSAT, SO-35) Non-Operational 1999-02-23 South Africa UoSat-OSCAR 36 (UOSAT 12, UO-36) Non-Operational 1999-04-21 UK ASU-OSCAR 37 (AO-37, ASUsat-1, ASUSAT) Non-Operational 2000-01-27 USA OPAL-OSCAR 38 (OO-38, StenSat, OPAL) Non-Operational 2000-01-27 USA Weber-OSCAR 39 (WO-39, JAWSAT) Non-Operational 2000-01-27 USA Saudi-OSCAR 41 (SO-41, Saudisat 1A) Non-Operational 2000-09-26 Saudi Arabia Saudi-OSCAR 42 (SO-42, Saudisat 1B) Non-Operational 2000-09-26 Saudi Arabia Malaysian-OSCAR 46 (MO-46, TIUNGSAT-1) Non-Operational 2000-09-26 Malaysia AMSAT-OSCAR 40 (AO-40, Phase 3D, P3D) Non-Operational 2000-11-16 USA Starshine-OSCAR 43 (SO-43, Starshine 3) Decayed 2001-09-30 USA Navy-OSCAR 44 (NO-44, PCSat) Semi-Operational 2001-09-30 USA Navy-OSCAR 45 (NO-45, Sapphire) Non-Operational 2001-09-30 USA BreizhSAT-OSCAR 47 (BO-47, IDEFIX CU1) Non-Operational 2002-05-04 France BreizhSAT-OSCAR 48 (BO-48, IDEFIX CU2) Non-Operational 2002-05-04 France AATiS-OSCAR 49 (AO-49, Safir-M, RUBIN 2) Non-Operational 2002-12-20 Germany Saudi-OSCAR 50 (SO-50, Saudisat-1C) Operational 2002-12-20 Saudi Arabia CubeSat-OSCAR 55 (Cute-1) Operational 2003-06-30 Japan CubeSat-OSCAR 57 (CubeSat-XI-IV) Operational 2003-06-30 Japan CanX-1 Non-Operational 2003-06-30 Canada DTUSat Decayed 2003-06-30 Denmark AAU Cubesat Non-Operational 2003-06-30 Denmark RS-22 (Mozhayets 4) Operational 2003-09-27 Russia AMSAT-OSCAR 51 (Echo, AO-51) Non-Operational 2004-06-28 USA VUSat-OSCAR 52 (HAMSAT, VO-52, VUSat) Operational 2005-05-05 India / Netherlands PCSat2 (PCSAT2) Decayed 2005-08-03 USA AMSAT-OSCAR 54 (AO-54, SuitSat, Radioskaf) Decayed 2005-09-08 International eXpress-OSCAR 53 (XO-53, SSETI Express) Non-Operational 2005-10-27 ESA CubeSat-OSCAR 58 (CO-58, Cubesat XI-V) Operational 2005-10-27 Japan UWE-1 Non-Operational 2005-10-27 Germany NCube-2 Non-Operational 2005-10-27 Norway CubeSat-OSCAR 56 (CO-56, Cute-1.7) Non-Operational 2006-02-21 Japan K7RR-Sat Non-Operational 2006-07-26 USA CP2 Non-Operational 2006-07-26 USA HAUSAT 1 Non-Operational 2006-07-26 South Korea ICE Cube 1 Non-Operational 2006-07-26 USA ICE Cube 2 Non-Operational 2006-07-26 USA ION Non-Operational 2006-07-26 USA KUTESat Non-Operational 2006-07-26 USA MEROPE Non-Operational 2006-07-26 USA nCUBE 1 Non-Operational 2006-07-26 RINCON Non-Operational 2006-07-26 USA SACRED Non-Operational 2006-07-26 USA SEEDS Non-Operational 2006-07-26 Japan Voyager Non-Operational 2006-07-26 USA PicPot Non-Operational 2006-07-26 Italy HITSat-OSCAR 59 (HITSat, HO-59) Non-Operational 2006-09-22 Japan GeneSat-1 Operational 2006-12-16 USA Navy-OSCAR 60 (RAFT, NO-60) Decayed 2006-12-21 USA Navy-OSCAR 61 (ANDE, NO-61) Decayed 2006-12-21 USA Navy-OSCAR 62 (FCAL, NO-62) Decayed 2006-12-21 USA Libertad-1 Non-Operational 2007-04-17 Colombia CAPE-1 Semi-Operational 2007-04-17 USA CP3 Non-Operational 2007-04-17 USA CP4 Non-Operational 2007-04-17 USA Pehuensat-OSCAR 63 (PEHUENSAT-1, PO-63) Decayed 2007-10-01 Argentina Delfi-OSCAR 64 (Delfi-C3, DO-64) Semi-Operational 2008-04-28 Netherlands Cubesat-OSCAR 65 (Cute-1.7+APD II, CO-65) Operational 2008-04-28 Japan Cubesat-OSCAR 66 (SEED II, CO-66) Operational 2008-04-28 Japan COMPASS-1 Semi-Operational 2008-04-28 Germany RS-30 (Yubileiny) Operational 2008-05-23 Russia PRISM (HITOMI) Operational 2009-01-23 Japan KKS-1 (KISEKI) Operational 2009-01-23 Japan STARS (KUKAI) Unknown 2009-01-23 Japan Castor Unknown 2009-07-30 USA Pollux Non-Operational 2009-07-30 USA Aggiesat2 Decayed 2009-07-30 USA PARADIGM (BEVO-1) Decayed 2009-07-30 USA Sumbandila-OSCAR 67 (SumbandilaSat, SO-67) Non-Operational 2009-09-17 South Africa SwissCube Operational 2009-09-23 Switzerland ITUpSAT1 Operational 2009-09-23 Turkey UWE-2 Operational 2009-09-23 Germany BEESAT Operational 2009-09-23 Germany Hope Oscar 68 (XW-1, HO-68) Beacon-Operational 2009-12-15 China AubieSat-1 (AO-71) Operational 2011-10-28 USA ESTCube-1 Operational 2013-05-07 Estonia AMSAT-OSCAR 73 (FUNcube-1, AO-73) Operational 2013-11-21 UK
Low Earth Orbit FM OSCARs
A number of low earth orbit (LEO) OSCAR satellites use frequency modulation (FM). These are also commonly referred to as "FM LEO's" or the "FM Birds". Such satellites act as FM amateur radio repeaters that can be communicated through using omni-directional antennas and commonly available amateur radio equipment. Due to the relative ease of tuning FM as compared to SSB and the decreased distance of LEO satellites from earth stations communication can be achieved even with handheld transceivers and using manual doppler correction. The orbit of these satellites however causes the available time in which to communicate to be limited to only a few minutes per pass.
List of FM LEO satellites Satellite name OSCAR
Uplink (MHz) Downlink (MHz) CTCSS (Hz) Status Hope Oscar 68 7001680000000000000HO-68 145.825 FM 435.675 FM 67.0 Beacon-Operational Sumbandila Oscar 671 7001670000000000000SO-67 145.875 FM 435.345 FM N/A Non-Operational AMSAT-OSCAR 512 7001511000000000000AO-51 145.880 FM 435.150 FM N/A Non-Operational AMSAT-OSCAR 512 7001512000000000000AO-51 145.920 FM 435.300 FM 67.0 Non-Operational AMSAT-OSCAR 512 7001513000000000000AO-51 145.880 FM 2401.200 FM N/A Non-Operational AMSAT-OSCAR 512 7001514000000000000AO-51 1268.700 FM 435.300 FM 67.0 Non-Operational AMSAT-OSCAR 512 7001515000000000000AO-51 1268.700 FM 2401.200 FM 67.0 Non-Operational Saudi-OSCAR 50 7001500000000000000SO-50 145.850 FM 436.795 FM 67.0
(74.4 to activate)
Operational Saudi-OSCAR 41 7001410000000000000SO-41 145.850 FM 436.775 FM N/A Non-Operational SUNSAT-OSCAR 35 7001351000000000000SO-35 145.825 FM 436.250 FM N/A Non-Operational SUNSAT-OSCAR 35 7001352000000000000SO-35 436.291 FM 145.825 FM N/A Non-Operational SUNSAT-OSCAR 35 7001353009999900000SO-35 1265.000 FM 436.2500 FM N/A Non-Operational ISS3 5000000000000000000ARISS 437.800 FM 145.800 FM N/A Operational AMRAD-OSCAR 274 7001270000000000000AO-27 145.850 FM 436.795 FM N/A Non-Operational AMSAT-OSCAR 16 7001160000000000000AO-16 145.920 FM 437.026 DSB-SC5 N/A Semi-Operational UoSAT-OSCAR 14 7001140000000000000UO-14 145.975 FM 435.070 FM N/A Non-Operational Note 1: SO-67 suffered a power board failure. The team still hopes recovery to amateur radio operations is possible.
Note 2: As of November 29, 2011 AO-51 has ceased all transmissions.
Note 3: The ISS FM repeater is rarely activated.
Note 4: AO-27 FM Repeater is stuck on bootloader. The team is working on a fix.
Currently 23 countries have launched an OSCAR satellite. These countries, in chronological order by date of launch, include: The United States of America, Australia, Spain, the United Kingdom, Japan, Brazil, Argentina, Pakistan, Russia, France, Portugal, Korea, Italy, Mexico, Israel, Thailand, South Africa, Malaysia, Saudi Arabia, Germany, India, Colombia, and the Netherlands.
Satellites in development
|This section's factual accuracy may be compromised due to out-of-date information. (November 2010)|
- IRSHSAT-1 - A cubesat is being built by the students at Pakistan Student Satellite Program. Launch Date sometime in 2011.
- BLUEsat - A microsatellite built by the students of The University of New South Wales. Unknown launch date. The next test will be in April 2014 when it is flown from a stratospheric weather balloon. 
- ZSAT - A microsatellite initiated and funded by the U.S. Department of Science and Technology[clarification needed]. Unknown launch date.
- AMSAT-Phase 3E - A satellite built by AMSAT. Delayed Indefinitely.
- KiwiSAT - A microsatellite built by AMSAT-ZL. Scheduled to launch from mid to late 2009
- ESEO - A microsatellite built by SSETI. Scheduled to launch in 2015-2016. 
- AMSAT-Eagle - A satellite built by AMSAT. Cancelled. 
- Delfi-n3Xt - The second nano-satellite from Delft University of Technology. Scheduled to launch in November of 2013.
- Fox-1 - A 1u cubesat from AMSAT-NA. Scheduled to launch in the November of 2014. 
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).
- "SA AMSAT". Southern African Amateur Radio Satellite Association. Retrieved 2012-08-09.
- "AMSAT AO-51 Control Team News". AO-51 Command Team and Operations Group. Retrieved 2012-01-15.
- "ISS Fan Club". ISS Fan Club. Retrieved 2011-07-27.
- "Official AO-27 HomePage". AO-27 Control Operators Association. Retrieved 2013-01-06.
- "2010 AMSAT Field Day Competition" (PDF). The Radio Amateur Satellite Corporation. 2010. p. 1. Retrieved 2011-07-26. "...the FM voice satellites like AMSAT-OSCAR 16, AMRAD-OSCAR-27, SaudiSat-Oscar-50, or AMSAT-OSCAR-51..."
- "AMSAT OSCAR 16 (PacSAT)". The Radio Amateur Satellite Corporation. Retrieved 2011-07-26. "Mode FM Voice Repeater (Downlink is DSB. Operation is Intermittent)"
- "Space Satellites from the World's Garage -- The Story of AMSAT". The Radio Amateur Satellite Corporation. Retrieved 2006-09-05.
- "The Extraordinary History of Amateur Radio Satellites". Space Today Online. Retrieved 2006-09-05.
- "Satellite Development Programs". The Radio Amateur Satellite Corporation. Retrieved 2006-09-05.
|Wikimedia Commons has media related to OSCAR.|
- AMSAT Corporation a nonprofit corporation that coordinates construction and launch of the satellites
- Project OSCAR organization that built "OSCAR-1"
- NASA J-Track Amateur Track amateur satellites in real-time
- SSTL Builders and operators of the UoSat series satellites
- Work-Sat Work the FM satellites - with equipment most hams already own!