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40-474: The first crew hand launched an amateur radio satellite , the T-6 mission included a visiting Frenchman, and T-7 included the first woman in space in 20 years. It was the first mission to Salyut 7, but more than one spacecraft could be docked to S7 at a time, which is why the later missions could overlap with Soyuz T-5. The spacecraft launched with two people ("Elbrus crew"), and returned with three ("Dnieper crew"). This

80-575: A linear transponder for two-way communications in real time. Some satellites have a bulletin board for store-and-forward digital communications, or a digipeater for direct packet radio connections. Amateur satellites have been launched into low Earth orbits and into highly elliptical orbits . Currently, amateur satellites support many different types of operation, including FM voice and SSB voice, as well as digital communications of AX.25 FSK ( Packet radio ) and PSK-31 . Uplink and downlink designations use sets of paired letters following

120-504: A coded identifying signal in response to an interrogating received signal. In a communications satellite , a satellite transponder receives signals over a range of uplink frequencies, usually from a satellite ground station ; the transponder amplifies them, and re-transmits them on a different set of downlink frequencies to receivers on Earth, often without changing the content of the received signal or signals. A communications satellite ’s channels are called transponders because each

160-414: A lap they swipe or touch the receiver which is connected to a computer and log their lap time. NASCAR uses transponders and cable loops placed at numerous points around the track to determine the lineup during a caution period. This system replaced a dangerous race back to the start-finish line . Many modern automobiles have keys with transponders hidden inside the plastic head of the key. The user of

200-520: A result, differences in transponder functionality also might influence the functional description of related optical modules like transceivers and muxponders . Another type of transponder occurs in identification friend or foe (IFF) systems in military aviation and in air traffic control secondary surveillance radar (beacon radar) systems for general aviation and commercial aviation . Primary radar works best with large all-metal aircraft, but not so well on small, composite aircraft. Its range

240-418: A ship's radar screen. Sonar transponders operate under water and are used to measure distance and form the basis of underwater location marking, position tracking and navigation . Electronic toll collection systems such as E-ZPass in the eastern United States use RFID transponders to identify vehicles. Transponders are used in races for lap timing. A cable loop is dug into the race circuit near to

280-542: Is a list of major amateur satellites in Japanese Misplaced Pages ). Es’hail 2 / QO-100 Launched November 15, 2018.In geostationary orbit covering Brazil to Thailand. Narrowband Linear transponder 2400.050 - 2400.300 MHz Uplink 10489.550 - 10489.800 MHz Downlink Wideband digital transponder 2401.500 - 2409.500 MHz Uplink 10491.000 - 10499.000 MHz Downlink The first amateur satellites contained telemetry beacons. Since 1965, most OSCARs carry

320-567: Is a separate transceiver or repeater . With digital video data compression and multiplexing , several video and audio channels may travel through a single transponder on a single wideband carrier . Original analog video only has one channel per transponder, with subcarriers for audio and automatic transmission identification service ( ATIS ). Non-multiplexed radio stations can also travel in single channel per carrier (SCPC) mode, with multiple carriers (analog or digital) per transponder. This allows each station to transmit directly to

360-405: Is also limited by terrain and rain or snow and also detects unwanted objects such as automobiles, hills and trees. Furthermore, it cannot always estimate the altitude of an aircraft. Secondary radar overcomes these limitations but it depends on a transponder in the aircraft to respond to interrogations from the ground station to make the plane more visible. Depending on the type of interrogation,

400-697: 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 helped advance

440-412: Is mandatory in controlled airspace in many countries. Some countries have also required, or are moving toward requiring, that all aircraft be equipped with Mode S, even in uncontrolled airspace . However, in the field of general aviation there have been objections to these moves, because of the cost, size, limited benefit to the users in uncontrolled airspace, and, in the case of balloons and gliders ,

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480-670: 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. A number of low Earth orbit (LEO) OSCAR satellites use frequency modulation (FM). These are also commonly referred to as "FM LEOs" or the "FM Birds". Such satellites act as FM amateur radio repeaters that can be communicated through using commonly available amateur radio equipment. Communication can be achieved with handheld transceivers using manual doppler correction. Satellite passes are typically less than 15 minutes long. The names of

520-451: Is published by AMSAT . AMSAT has not been actively involved in the launch and operation of most amateur satellites in the last two decades beyond allocating an OSCAR number. The first amateur satellite, simply named OSCAR 1, was launched on December 12, 1961, barely four years after the launch of the world's first satellite, Sputnik I . The satellite had to be built in a very specific shape and weight, so it could be used in place of one of

560-450: 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 to be received by the satellite. After the satellite passes overhead and begins to move away, this process is reversed. The downlink frequency will appear lower and the uplink frequency will need to be adjusted higher . The following mathematical formulas relate

600-450: The 435-438 MHz band is particularly popular for amateur/educational small satellites such as Cubesats. Transponder In telecommunications , a transponder is a device that, upon receiving a signal, emits a different signal in response. The term is a blend of transmitter and responder . In air navigation or radio frequency identification , a flight transponder is an automated transceiver in an aircraft that emits

640-467: 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 effect correction . Manual frequency-shift correction

680-474: The Earth's atmosphere (or never successfully left it). The country listing denotes the country that constructed the satellite and not the launching country. Currently, 30 countries have launched an OSCAR satellite. These countries, in chronological order by date of launch, include: SuitSat , an obsolete Russian space suit with a transmitter aboard, was officially known as "AMSAT-OSCAR 54". Coincidentally, "Oscar"

720-505: The Elbrus crew closed the hatch from the work compartment into the intermediate compartment so the TsUP could pump fuel from Progress 13 to Salyut 7. The crew monitored the operation but played little active role in it. May 29 was spent organizing the supplies delivered. At the same time, according to Lebedev, “we filled the resupply ship with what we don’t need and tied them down with ropes. When I enter

760-580: The Soyuz T-7 spacecraft in December 1982. 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

800-472: The aft end of the Progress pointed toward Earth. This placed the station in gravity-gradient stabilization . Lebedev remarked in his diary that the attitude control jets were “very noisy,” and that they sounded like “hitting a barrel with a sledgehammer.” Of Salyut 7 during the unpacking of Progress 13, Lebedev said, “It looks like we’re getting ready to move or have just moved to a new apartment.” The following day

840-513: The airplane-based tests. Once it was found to be operative and reliable, the satellite was shipped to Kennedy Space Center, where it was mounted in the launch vehicle's third stage . OSCAR 10's dimensions were: Height: 1.35 m (53 in) Width: 2.0 m (78.75 in) Weight: 140 kg at launch; 90 kg post engine firings. Other programs besides OSCAR have included Iskra (Soviet Union) circa 1982, JAS-1 (Fuji-OSCAR 12) (Japan) in 1986, RS (Soviet Union and Russia), and CubeSats . (There

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880-546: The car may not even be aware that the transponder is there, because there are no buttons to press. When a key is inserted into the ignition lock cylinder and turned, the car's computer sends a signal to the transponder. Unless the transponder replies with a valid code, the computer will not allow the engine to be started. Transponder keys have no battery; they are energized by the signal itself. Transponders may also be used by residents to enter their gated communities . However, having more than one transponder causes problems. If

920-472: The components for OSCAR 10 were "off the shelf". Jan King led the project. Solar cells were bought in batches of 10 or 20 from Radio Shack , and tested for efficiency by group members. 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, and flown a couple of times to evaluate its performance and reliability. Special QSL cards were issued to those who participated in

960-469: The first plants to flower and produce seeds in the zero gravity of space, a Guinness World Record. The Soyuz T-5 spacecraft was undocked in August 1982, leaving Salyut 7 and Soyuz T-7 spacecraft in orbit. The spacecraft returned to Earth successfully with Popov, Serebrov and Savitskaya, also called the "Dneiper crew". The Soyuz T-5 had been in space six weeks. The initial "Elbrus crew", would return to Earth in

1000-466: The high orbital speed of the amateur 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. Hence, the receiver frequency at the ground station must be adjusted higher to continue receiving

1040-460: The launch vehicle ballast weights. OSCAR 1 was the first satellite to be ejected as a secondary payload (the primary payload was Discoverer 36 ) and to subsequently enter a separate orbit. It carried no on-board propulsion and its orbit decayed quickly. Despite orbiting for only 22 days, OSCAR 1 was an immediate success and led to follow-on missions. Over 570 amateur radio operators in 28 countries forwarded observations to Project OSCAR. Most of

1080-460: The majority of service-allocations stipulated in this document were incorporated in national Tables of Frequency Allocations and Utilisations which is within the responsibility of the appropriate national administration. The allocation might be primary, secondary, exclusive, and shared. In addition to the formal allocations in the main table such as above, there is also a key ITU-R footnote RR 5.282 that provides for additional allocations:- Of these,

1120-466: The power requirements during long flights. Transponders are used on some military aircraft to ensure ground personnel can verify the functionality of a missile’s flight termination system prior to launch. Such radar-enhancing transponders are needed as the enclosed weapon bays on modern aircraft interfere with prelaunch, flight termination system verification performed by range safety personnel during training test launches. The transponders re-radiate

1160-509: The resupply ship, it jingles with a metallic sound, so when we separate it will sound like a brass band.” Progress 13 pumped 300 liters of water aboard on May 31. On June 2 Progress 13 lowered the station's orbit to 300 km to receive Soyuz T-6. In July, Valentin Lebedev, in charge of the plant experiments, reported that the Arabidopsis plants, chosen for their short 40-day lifecycle, had become

1200-464: The same purposes as those of the amateur service .» This radiocommunication service is classified in accordance with ITU Radio Regulations (article 1) as follows: Radiocommunication service (article 1.19) The allocation of radio frequencies is provided according to Article 5 of the ITU Radio Regulations (edition 2012). In order to improve harmonisation in spectrum utilisation,

1240-530: The satellite, rather than paying for a whole transponder, or using landlines to send it to an earth station for multiplexing with other stations. In fiber-optic communications , a transponder is the element that sends and receives the optical signal from a fiber . A transponder is typically characterized by its data rate and the maximum distance the signal can travel. The term "transponder" can apply to different items with important functional differences, mentioned across academic and commercial literature: As

Soyuz T-5 - Misplaced Pages Continue

1280-416: 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

1320-475: The science of satellite communications. Contributions include the launch of the first satellite voice transponder (OSCAR 3) and the development of highly advanced digital "store-and-forward" messaging transponder techniques. The Amateur Radio Satellite community is very active in building satellites and in finding launch opportunities. Lists of functioning satellites need updating regularly, as new satellites are launched and older ones fail. Current information

1360-833: The signals allowing for much longer communication distances. The International Maritime Organization 's International Convention for the Safety of Life at Sea (SOLAS) requires the Automatic Identification System (AIS) to be fitted aboard international voyaging ships with 300 or more  gross tonnage  (GT), and all passenger ships regardless of size. AIS transmitters/receivers are generally called transponders , but they generally transmit autonomously, although coast stations can interrogate class B transponders on smaller vessels for additional information. In addition, navigational aids often have transponders called RACON (radar beacons) designed to make them stand out on

1400-436: The start/finish line. Each individual runner or car has an active transponder with a unique ID code. When the individual passes the start/finish line, the lap time and the racing position is shown on the score board. Passive and active RFID systems are used in motor sports , and off-road events such as Enduro and Hare and Hounds racing, the riders have a transponder on their person, normally on their arm. When they complete

1440-496: The structure X/Y where X is the uplink band and Y is the downlink band. Occasionally, the downlink letter is rendered in lower case (i.e., X/y ). With a few exceptions, the letters correspond to IEEE's standard for radar frequency letter bands... Prior to the launch of OSCAR 40, operating modes were designated using single letters to indicate both uplink and downlink bands. While deprecated, these older mode designations are still widely used in casual conversation. Due to

1480-467: The transponder sends back a transponder code (or "squawk code", Mode A) or altitude information (Mode C) to help air traffic controllers to identify the aircraft and to maintain separation between planes. Another mode called Mode S (Mode Select) is designed to help avoiding over-interrogation of the transponder (having many radars in busy areas) and to allow automatic collision avoidance. Mode S transponders are backward compatible with Modes A and C. Mode S

1520-427: Was continuously available hot water. The Elbrus crew ejected a 28-kg amateur radio satellite from a Salyut 7 trash airlock on May 17, 1982. The Soviets called this the first launch of a communications satellite from a crewed space vehicle. They did this ahead of the launch of two large geostationary satellites from the U.S. Space Shuttle ( STS-5 , November 11–16, 1982). On May 25, the Elbrus crew reoriented Salyut 7 so

1560-463: Was the first (1st) expedition to the new Salyut 7 space station, launched into Earth orbit earlier in 1982. Salyut 7 was similar to the Salyut 6 (1977–1982) space station it superseded, but featured a number of improvements. The Soyuz T-5 spacecraft docked with Salyut 7 in orbit, and it was visited by the 2nd and 3rd expeditions to the space station. One advantage the new Salyut 7 station had over Salyut 6,

1600-620: Was the name given to an obsolete space suit by its young owner in the 1958 novel Have Space Suit—Will Travel , by Robert A. Heinlein . This book was first published a year after the launch of Sputnik 1 , the world's first artificial satellite. Amateur-satellite service (also: amateur-satellite radiocommunication service ) is – according to Article 1.57 of the International Telecommunication Union's (ITU) Radio Regulations (RR) – defined as « A radiocommunication service using space stations on earth satellites for

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