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UoSAT-1
UoSAT-1, also known as UoSAT-OSCAR 9 (UO-9), was a British amateur radio satellite which orbited Earth. It was built at the University of Surrey and launched into low Earth orbit on 6 October 1981. It exceeded its anticipated two-year orbital lifespan by six years, having received signals on 13 October 1989, before re-entering the atmosphere. This was the first of several UoSAT satellites; followed by UoSAT-2. Mission Like its successor UoSAT-2 it carried a CCD camera and a Digitalker speech synthesiser, and transmitted telemetry data on a 145.826 MHz beacon at 1200 baud using asynchronous AFSK. The ''Astrid'' package sold by British firm MM Microwave, consisting of a fixed frequency VHF receiver set and software for the BBC Micro, could display the telemetry frames from either UoSAT-1 or UoSAT-2. UoSAT-1's solar arrays were of an experimental design reused for UoSAT-2. Computers and Data Processing The primary computer for the satellite was the RCA 1802 The COSMAC ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UoSAT-2
UoSAT-2, which is also known as UO-11 and OSCAR-11, is a British satellite orbiting in Low Earth Orbit. The satellite functions as an amateur radio transmitter (known as an OSCAR) and was built at the University of Surrey. It launched into orbit in March 1984 and remains orbital and active, though unstable with irregular periods of transmission. All of the Analog telemetry channels have failed, making telemetry from OSCAR 11 useless. The satellite was still heard transmitting telemetry in 2015, thirty years after launch. It was operated by Surrey Satellite Technology Ltd. (SSTL). Characteristics The satellite was the second in the UoSAT series of satellites built by University of Surrey; preceded by UoSAT-1 and followed by UoSAT-3. The satellite carries a Digitalker speech synthesiser, magnetometers, a CCD camera, a Geiger-Müller tube, and a microphone to detect the vibrations of micrometeoroid impacts. Like UoSAT-1 it transmits telemetry data on the VHF beacon at 1200 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UO-11
UoSAT-2, which is also known as UO-11 and OSCAR-11, is a British satellite orbiting in Low Earth Orbit. The satellite functions as an amateur radio transmitter (known as an OSCAR) and was built at the University of Surrey. It launched into orbit in March 1984 and remains orbital and active, though unstable with irregular periods of transmission. All of the Analog telemetry channels have failed, making telemetry from OSCAR 11 useless. The satellite was still heard transmitting telemetry in 2015, thirty years after launch. It was operated by Surrey Satellite Technology Ltd. (SSTL). Characteristics The satellite was the second in the UoSAT series of satellites built by University of Surrey; preceded by UoSAT-1 and followed by UoSAT-3. The satellite carries a Digitalker speech synthesiser, magnetometers, a CCD camera, a Geiger-Müller tube, and a microphone to detect the vibrations of micrometeoroid impacts. Like UoSAT-1 it transmits telemetry data on the VHF beacon at 1200 b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
OSCAR
Oscar, OSCAR, or The Oscar may refer to: People * Oscar (given name), an Irish- and English-language name also used in other languages; the article includes the names Oskar, Oskari, Oszkár, Óscar, and other forms. * Oscar (Irish mythology), legendary figure, son of Oisín and grandson of Finn mac Cumhall Places * Oscar, Kentucky, an unincorporated community * Oscar, Louisiana, an unincorporated community * Oscar, Missouri, an unincorporated community * Oscar, Oklahoma, an unincorporated community * Oscar, Pennsylvania, an unincorporated community * Oscar, Texas, an unincorporated community * Oscar, West Virginia, an unincorporated community * Lake Oscar (other) * Oscar Township, Otter Tail County, Minnesota, a civil township Animals * Oscar (bionic cat), a cat that had implants after losing both hind paws * Oscar (bull), #16, (d. 1983) a ProRodeo Hall of Fame bucking bull * Oscar (fish), ''Astronotus ocellatus'' * Oscar (therapy cat), cat purported to predi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amateur Radio Satellites
An amateur () is generally considered a person who pursues an avocation independent from their source of income. Amateurs and their pursuits are also described as popular, informal, self-taught, user-generated, DIY, and hobbyist. History Historically, the amateur was considered to be the ideal balance between pure intent, open mind, and the interest or passion for a subject. That ideology spanned many different fields of interest. It may have its roots in the ancient Greek philosophy of amateur athletes competing in the Olympics. The ancient Greek citizens spent most of their time in other pursuits, but competed according to their natural talents and abilities. The "gentleman amateur" was a phenomenon among the gentry of Great Britain from the 17th century until the 20th century. With the start of the Age of Reason, with people thinking more about how the world works around them, (see science in the Age of Enlightenment), things like the cabinets of curiosities, and the ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BBC Micro
The British Broadcasting Corporation Microcomputer System, or BBC Micro, is a series of microcomputers and associated peripherals designed and built by Acorn Computers in the 1980s for the BBC Computer Literacy Project. Designed with an emphasis on education, it was notable for its ruggedness, expandability, and the quality of its operating system. An accompanying 1982 television series, '' The Computer Programme'', featuring Chris Serle learning to use the machine, was broadcast on BBC2. After the Literacy Project's call for bids for a computer to accompany the TV programmes and literature, Acorn won the contract with the ''Proton'', a successor of its Atom computer prototyped at short notice. Renamed the BBC Micro, the system was adopted by most schools in the United Kingdom, changing Acorn's fortunes. It was also successful as a home computer in the UK, despite its high cost. Acorn later employed the machine to simulate and develop the ARM architecture. While nine mod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AFSK
Frequency-shift keying (FSK) is a frequency modulation scheme in which digital information is transmitted through discrete frequency changes of a carrier signal. The technology is used for communication systems such as telemetry, weather balloon radiosondes, caller ID, garage door openers, and low frequency radio transmission in the VLF and ELF bands. The simplest FSK is binary FSK (BFSK). BFSK uses a pair of discrete frequencies to transmit binary (0s and 1s) information. With this scheme, the 1 is called the mark frequency and the 0 is called the space frequency. Modulating and demodulating Reference implementations of FSK modems exist and are documented in detail. The demodulation of a binary FSK signal can be done using the Goertzel algorithm very efficiently, even on low-power microcontrollers. Variations Multiple frequency-shift keying Continuous-phase frequency-shift keying In principle FSK can be implemented by using completely independent free-running osc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Micro User
''The Micro User'' (titled ''BBC Micro User'' in the first three issues) was a British specialist magazine catering to users of the BBC Microcomputer series, Acorn Electron, Acorn Archimedes and, to a limited extent, the Cambridge Z88. It had a comprehensive mix of reviews of games, application software, and the latest Acorn Computers, Acorn computers; type-in programs (duplicated on a "cover disk" which was available separately), a correspondence page offering help with computer problems, and approachable technical articles on programming and the BBC Micro's internals. The magazine hosted the long-running ''Body Building'' series by Mike Cook, in which each article introduced a small electronics project that could be built and connected to one of the BBC Micro's I/O ports. The project could be ordered in kit form or fully assembled, or the reader could source the parts and design as the articles contained a circuit diagram. There were regular columns on Adventure game, adventur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speech Synthesis
Speech synthesis is the artificial production of human speech. A computer system used for this purpose is called a speech synthesizer, and can be implemented in software or hardware products. A text-to-speech (TTS) system converts normal language text into speech; other systems render symbolic linguistic representations like phonetic transcriptions into speech. The reverse process is speech recognition. Synthesized speech can be created by concatenating pieces of recorded speech that are stored in a database. Systems differ in the size of the stored speech units; a system that stores phones or diphones provides the largest output range, but may lack clarity. For specific usage domains, the storage of entire words or sentences allows for high-quality output. Alternatively, a synthesizer can incorporate a model of the vocal tract and other human voice characteristics to create a completely "synthetic" voice output. The quality of a speech synthesizer is judged by its similarity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Low Earth Orbit
A low Earth orbit (LEO) is an orbit around Earth with a period of 128 minutes or less (making at least 11.25 orbits per day) and an eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, with an altitude never more than about one-third of the radius of Earth. The term ''LEO region'' is also used for the area of space below an altitude of (about one-third of Earth's radius). Objects in orbits that pass through this zone, even if they have an apogee further out or are sub-orbital, are carefully tracked since they present a collision risk to the many LEO satellites. All crewed space stations to date have been within LEO. From 1968 to 1972, the Apollo program's lunar missions sent humans beyond LEO. Since the end of the Apollo program, no human spaceflights have been beyond LEO. Defining characteristics A wide variety of sources define LEO in terms of altitude. The altitude of an object in an elliptic orbit can vary significantly along the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Surrey
The University of Surrey is a public research university in Guildford, Surrey, England. The university received its royal charter in 1966, along with a number of other institutions following recommendations in the Robbins Report. The institution was previously known as Battersea College of Technology and was located in Battersea Park, London. Its roots however, go back to Battersea Polytechnic Institute, founded in 1891 to provide further and higher education in London, including its poorer inhabitants. The university's research output and global partnerships have led to it being regarded as one of the UK's leading research universities. The university is a member of the Association of MBAs and is one of four universities in the University Global Partnership Network. It is also part of the SETsquared partnership along with the University of Bath, the University of Bristol, the University of Southampton and the University of Exeter. The university's main campus is on Sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
