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AMSAT
AMSAT is a name for various amateur radio satellite organizations worldwide. In particular, it often refers to the Radio Amateur Satellite Corporation, headquartered in Washington, D.C. AMSAT organizations design, build, arrange launches for, and then operate (command) satellites carrying amateur radio payloads, including the OSCAR series of satellites. Other informally affiliated national organizations exist, such as AMSAT Germany (AMSAT-DL) and AMSAT Japan (JAMSAT). History AMSAT was founded in 1969 in Washington, D.C. to continue the efforts begun by OSCAR, Project OSCAR. Its first project was to coordinate the launch of Australis-OSCAR 5, OSCAR 5, constructed by students at the University of Melbourne. Some design modifications were needed and were made by AMSAT members, and the satellite was successfully launched on 30 January 1970, on a NASA Delta (rocket family), Thor Delta launch vehicle. AMSAT's next launch was AMSAT-OSCAR 6 (AO-6) on 15 October 1972. AO-6 was AMSAT' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amateur Radio Satellite
An amateur radio satellite is an artificial satellite built and used by amateur radio operators. It forms part of the Amateur-satellite service. These satellites use amateur radio frequency allocations to facilitate communication between amateur radio stations. Many amateur satellites receive an OSCAR designation, which is an acronym for Orbiting Satellite Carrying Amateur Radio. The designation is assigned by AMSAT, an organization which promotes the development and launch of amateur radio satellites. Because of the prevalence of this designation, amateur radio satellites are often referred to as OSCARs. These satellites can be used free of charge by licensed amateur radio operators for voice ( FM, SSB) and data ( AX.25, packet radio, APRS) communications. Currently, over 18 fully operational amateur radio satellites are in orbit. They may be designed to act as repeaters, as linear transponders, and as store and forward digital relays. Amateur radio satellites have helpe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AMSAT-OSCAR 7
AMSAT-OSCAR 7, or AO-7, is the second Phase 2 amateur radio satellite constructed by the Radio Amateur Satellite Corporation (AMSAT). It was launched into Low Earth Orbit on November 15, 1974 and remained operational until a battery failure in 1981. After 21 years of apparent silence, the satellite was heard again on June 21, 2002 – 27 years after launch. At that time the public learned that the satellite had remained intermittently functional and was used surreptitiously for communication by the anticommunist opposition Fighting Solidarity during martial law in Poland. AO-7 is the oldest operational satellite, be it government, scientific, military or commercial. It carries two amateur radio transponders. Its "Mode A" transponder has an uplink on the 2-meter band and a downlink on the 10-meter band. The "Mode B" transponder has an uplink on the 70-centimeter band and a downlink on the 2-meter band. The satellite also carries four beacons which are designed to operate on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AO-40
AMSAT-OSCAR-40, also known as AO-40 or simply OSCAR 40, was the on-orbit designation of an amateur radio satellite of the OSCAR series. Prior to launch, the spacecraft was known as Phase 3D or "P3D". AO-40 was built by AMSAT. AO-40's project manager was Peter Guelzow of AMSAT-DL, the German AMSAT organization. Mr Guelzow holds amateur call sign DB2OS. History Design, construction and launch Following the failure of the Phase 3A launcher, design studies were undertaken and construction started for two successor satellites, that became AO-10 (Phase 3B) and AO-13 (Phase 3C) respectively. After the launch of AO-13, design commenced for a Phase 4 satellite. This idea was later shelved, and design of Phase 3D (on-orbit name: AO-40) was undertaken under direction of the project team based in Germany, involving amateur radio payloads from many countries in Europe. Assembly was done at AMSAT's Spacecraft Integration Facility in the 'Free Trade Zone Building' at the Orlando In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australis-OSCAR 5
Australis-OSCAR 5 (a.k.a. AO-5) is an amateur radio satellite that was launched into Low Earth Orbit on 23 January 1970 by a Thor Delta launcher from Vandenberg Air Force Base, Lompoc, California. AO-5 was launched piggyback with TIROS-M (ITOS-1) weather satellite). Spacecraft Built by students at The University of Melbourne, Melbourne, Victoria, Australia. Battery powered, Australis-OSCAR 5 transmitted telemetry on both 2 meter (144.050 MHz at 50 mW) and 10 meter (29.450 MHz at 250 mW) bands that operated for 23 and 46 days respectively. Passive magnetic attitude stabilization was performed by carrying two bar magnets to align with the Earth's magnetic field in order to provide a favorable antenna footprint. The University of Melbourne compiled tracking reports from hundreds of stations in 27 countries. Firsts * First amateur satellite to be remotely controlled. * First amateur satellite launch coordinated by new AMSAT AMSAT is a name for various amateur radi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RCA 1802
The COSMAC (Complementary Symmetry Monolithic Array Computer) is an 8-bit microprocessor family introduced by RCA. It is historically notable as the first CMOS microprocessor. The first production model was the two-chip CDP1801R and CDP1801U, which were later combined into the single-chip CDP1802. The 1802 represented the majority of COSMAC production, and today the entire line is known simply as the RCA 1802. The processor design traces its history to an experimental home computer designed by Joseph Weisbecker in the early 1970s, built at his home using TTL components. RCA began development of the CMOS version of the processor design in 1973, sampling it in 1974 with plans to move to a single-chip implementation immediately. Jerry Herzog led the design of the single-chip version, which sampled in 1975 and entered production in 1976. In contrast to most designs of the era, which were fabricated using the NMOS process, the COSMAC was implemented in CMOS form and used static l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AMSAT-OSCAR 8
OSCAR 8 (also called AO-08, Phase 2D or Amsat P2D) is an American amateur radio satellite. It was developed and built by radio amateurs of the AMSAT and launched on March 5, 1978 as a secondary payload together with the Earth observation satellite Landsat 3 from Vandenberg Air Force Base, California, United States. The satellite had two linear transponders, from the 2-meter band (uplink) to the 10-meter band and the 70-centimeter band (downlink). Frequencies Transponder 1 * Uplink (MHz): 145.850 - 145.900 * Downlink (MHz): 29.400 - 29.500 * Beacon A beacon is an intentionally conspicuous device designed to attract attention to a specific location. A common example is the lighthouse, which draws attention to a fixed point that can be used to navigate around obstacles or into port. More mode ... (MHz): 29.402 * Mode: SSB CW Transponder 2 * Uplink (MHz): 145.900 - 146.000 * Downlink (MHz): 435.200 - 435.100 * Beacon (MHz): 435.095 * Mode: SSB CW References {{DEFAULTS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ariane 5
Ariane 5 is a retired European heavy-lift space launch vehicle operated by Arianespace for the European Space Agency (ESA). It was launched from the Guiana Space Centre (CSG) in French Guiana. It was used to deliver payloads into geostationary transfer orbit (GTO), low Earth orbit (LEO) or further into space. The launch vehicle had a streak of 82 consecutive successful launches between 9 April 2003 and 12 December 2017. Since 2014, Ariane 6, a direct successor system, first launched in 2024. The system was designed as an expendable launch vehicle by the ''Centre national d'études spatiales'' (CNES), the French government's space agency, in cooperation with various European partners. Despite not being a direct derivative of its predecessor launch vehicle program, it was classified as part of the Ariane rocket family. Aérospatiale, and later ArianeGroup, was the prime contractor for the manufacturing of the vehicles, leading a multi-country consortium of other European con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nonprofit Organization
A nonprofit organization (NPO), also known as a nonbusiness entity, nonprofit institution, not-for-profit organization, or simply a nonprofit, is a non-governmental (private) legal entity organized and operated for a collective, public, or social benefit, as opposed to an entity that operates as a business aiming to generate a Profit (accounting), profit for its owners. A nonprofit organization is subject to the non-distribution constraint: any revenues that exceed expenses must be committed to the organization's purpose, not taken by private parties. Depending on the local laws, charities are regularly organized as non-profits. A host of organizations may be non-profit, including some political organizations, schools, hospitals, business associations, churches, foundations, social clubs, and consumer cooperatives. Nonprofit entities may seek approval from governments to be Tax exemption, tax-exempt, and some may also qualify to receive tax-deductible contributions, but an enti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germany
Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total population of over 84 million in an area of , making it the most populous member state of the European Union. It borders Denmark to the north, Poland and the Czech Republic to the east, Austria and Switzerland to the south, and France, Luxembourg, Belgium, and the Netherlands to the west. The Capital of Germany, nation's capital and List of cities in Germany by population, most populous city is Berlin and its main financial centre is Frankfurt; the largest urban area is the Ruhr. Settlement in the territory of modern Germany began in the Lower Paleolithic, with various tribes inhabiting it from the Neolithic onward, chiefly the Celts. Various Germanic peoples, Germanic tribes have inhabited the northern parts of modern Germany since classical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars
Mars is the fourth planet from the Sun. It is also known as the "Red Planet", because of its orange-red appearance. Mars is a desert-like rocky planet with a tenuous carbon dioxide () atmosphere. At the average surface level the atmospheric pressure is a few thousandths of Earth's, atmospheric temperature ranges from and cosmic radiation is high. Mars retains some water, in the ground as well as thinly in the atmosphere, forming cirrus clouds, frost, larger polar regions of permafrost and ice caps (with seasonal snow), but no liquid surface water. Its surface gravity is roughly a third of Earth's or double that of the Moon. It is half as wide as Earth or twice the Moon, with a diameter of , and has a surface area the size of all the dry land of Earth. Fine dust is prevalent across the surface and the atmosphere, being picked up and spread at the low Martian gravity even by the weak wind of the tenuous atmosphere. The terrain of Mars roughly follows a north-south ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Threaded Code
In computer science, threaded code is a programming technique where the code has a form that essentially consists entirely of calls to subroutines. It is often used in compilers, which may generate code in that form or be implemented in that form themselves. The code may be processed by an interpreter or it may simply be a sequence of machine code call instructions. Threaded code has better density than code generated by alternative generation techniques and by alternative calling conventions. In cached architectures, it may execute slightly slower. However, a program that is small enough to fit in a computer processor's cache may run faster than a larger program that suffers many cache misses. Small programs may also be faster at thread switching, when other programs have filled the cache. Threaded code is best known for its use in many compilers of programming languages, such as Forth, many implementations of BASIC, some implementations of COBOL, early versions of B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
