Amateur radio , also known as ham radio , is the use of the radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport , contesting , and emergency communications . The term "amateur" is used to specify "a duly authorized person interested in radioelectric practice with a purely personal aim and without pecuniary interest" (either direct monetary or other similar reward); and to differentiate it from commercial broadcasting , public safety (such as police and fire), or professional two-way radio services (such as maritime, aviation, taxis, etc.).
93-480: PAVE PAWS ( PAVE Phased Array Warning System) is a complex Cold War early warning radar and computer system developed in 1980 to "detect and characterize a sea-launched ballistic missile attack against the United States". The first solid-state phased array deployed used a pair of Raytheon AN/FPS-115 phased array radar sets at each site to cover an azimuth angle of 240 degrees. Two sites were deployed in 1980 at
186-466: A call sign on the air to legally identify the operator or station. In some countries, the call sign assigned to the station must always be used, whereas in other countries, the call sign of either the operator or the station may be used. In certain jurisdictions, an operator may also select a "vanity" call sign although these must also conform to the issuing government's allocation and structure used for Amateur Radio call signs. Some jurisdictions require
279-406: A $ 289.5 million sustainment contract which Raytheon was awarded in 2012. It has been reported that the defenses of Taiwan's PAVE PAWS system include a land based Phalanx CIWS . Taiwan had explored the acquisition of a second PAVE PAWS set but in 2012 decided against the purchase as the first PAVE PAWS set was significantly over budget and behind schedule. The second system would have been located in
372-643: A 22–23 February 1984 System Design Review for the Southeast and Southwest radars. The Expansion's Development Test and Engineering testing commenced on 3 February 1986 at the Southeast Site (PAVE PAWS Site 3, Robins Air Force Base —completed 5 June) and 15 August at the Southwest Site (PAVE PAWS Site 4, Eldorado Air Force Station ). The Gulf Coast FPS-115s were operational in 1986 (Robins) and May 1987 (Eldorado IOC). In February 1995, all 4 radars were being netted by
465-582: A 5–7 March "final review of the East Coast PAVE PAWS EIS was held at Hq AFSC ", the site was accepted by ESD on 12 April. The "first radio frequency transmission" from the West Coast Site was 23 March 1979 (it was completed in October 1979). " ADCOM wanted four [PAVE PAWS] sites, but by the end of 1979 only two had been funded". The Cape Cod system reached Initial operating capability (IOC) as
558-452: A US citizen may operate under reciprocal agreements in Canada, but not a non-US citizen holding a US license. Many people start their involvement in amateur radio on social media or by finding a local club. Clubs often provide information about licensing, local operating practices, and technical advice. Newcomers also often study independently by purchasing books or other materials, sometimes with
651-441: A club or organization for a period of time before a higher class of license can be acquired. A reciprocal licensing agreement between two countries allows bearers of an amateur radio license in one country under certain conditions to legally operate an amateur radio station in the other country without having to obtain an amateur radio license from the country being visited, or the bearer of a valid license in one country can receive
744-464: A club or organization generally requires that an individual with a current and valid amateur radio license who is in good standing with the telecommunications authority assumes responsibility for any operations conducted under the club license or club call sign. A few countries may issue special licenses to novices or beginners that do not assign the individual a call sign but instead require the newly licensed individual to operate from stations licensed to
837-608: A fee to obtain such a vanity call sign; in others, such as the UK, a fee is not required and the vanity call sign may be selected when the license is applied for. The FCC in the U.S. discontinued its fee for vanity call sign applications in September 2015, but replaced it as $ 35 in 2022. Call sign structure as prescribed by the ITU consists of three parts which break down as follows, using the call sign ZS1NAT as an example: Many countries do not follow
930-558: A given period of time. In addition to contests, a number of amateur radio operating award schemes exist, sometimes suffixed with "on the Air", such as Summits on the Air , Islands on the Air, Worked All States and Jamboree on the Air . Amateur radio operators may also act as citizen scientists for propagation research and atmospheric science . Radio transmission permits are closely controlled by nations' governments because radio waves propagate beyond national boundaries, and therefore radio
1023-453: A national licensing process and may instead require prospective amateur radio operators to take the licensing examinations of a foreign country. In countries with the largest numbers of amateur radio licensees, such as Japan, the United States, Thailand, Canada, and most of the countries in Europe, there are frequent license examinations opportunities in major cities. Granting a separate license to
SECTION 10
#17328688832541116-432: A nuisance. The use of "ham" meaning "amateurish or unskilled" survives today sparsely in other disciplines (e.g. "ham actor"). The amateur radio community subsequently began to reclaim the word as a label of pride, and by the mid-20th century it had lost its pejorative meaning. Although not an acronym or initialism, it is often written as "HAM" in capital letters. The many facets of amateur radio attract practitioners with
1209-463: A number after to indicate the political region; prefix CY indicates geographic islands. Prefix VA1 or VE1 is Nova Scotia , VA2 / VE2 is Quebec , VA3 / VE3 is Ontario , VA4 / VE4 is Manitoba , VA5 / VE5 is Saskatchewan , VA6 / VE6 is Alberta , VA7 / VE7 is British Columbia , VE8 is the Northwest Territories , VE9 is New Brunswick , VY0
1302-411: A peak power of 320 W, so the peak power of each array is 580 kW. It operates in a repeating 54 millisecond cycle in which it transmits a series of pulses, then listens for echoes. Its duty cycle (fraction of time spent transmitting) is never greater than 25% (so the average power of the beam never exceeds 25% of 540 kW, or 145 kW) and is usually around 18%. It is reported to have
1395-409: A pool of at least 350. To pass, 26 of the 35 questions must be answered correctly. The Extra Class exam has 50 multiple choice questions (drawn randomly from a pool of at least 500), 37 of which must be answered correctly. The tests cover regulations, customs, and technical knowledge, such as FCC provisions, operating practices, advanced electronics theory, radio equipment design, and safety. Morse Code
1488-419: A range of about 3,000 nautical miles (3,452 statute miles, 5,555 km); at that range it can detect an object the size of a small car, and smaller objects at closer ranges. The functioning of the radar is completely automatic, controlled by four computers. The software divides the beam time between "surveillance" and "tracking" functions, switching the beam back and forth rapidly between different tasks. In
1581-555: A second mission of tracking satellites and other objects in Earth orbit as part of the United States Space Surveillance Network . A notable feature of the system is its phased array antenna technology, it was one of the first large phased array radars. A phased array was used because a conventional mechanically-rotated radar antenna cannot turn fast enough to track multiple ballistic missiles. A nuclear strike on
1674-436: A separate license and a call sign in another country, both of which have a mutually-agreed reciprocal licensing approvals. Reciprocal licensing requirements vary from country to country. Some countries have bilateral or multilateral reciprocal operating agreements allowing hams to operate within their borders with a single set of requirements. Some countries lack reciprocal licensing systems. Others use international bodies such as
1767-573: A three-letter code. Thus, the AN/FPS-115 represents the 115th design of an Army-Navy “Fixed, Radar, Search” electronic device. The radar was built in the Cold War to give early warning of a nuclear attack , to allow time for US bombers to get off the ground and land-based US missiles to be launched, to decrease the chance that a preemptive strike could destroy US strategic nuclear forces. The deployment of submarine launched ballistic missiles (SLBMs) by
1860-404: A unique identifying call sign , which must be used in all transmissions. Amateur operators must hold an amateur radio license which is obtained by passing a government test demonstrating adequate technical radio knowledge and legal knowledge of the host government's radio regulations. Radio amateurs are limited to a specific set of frequency bands, the amateur radio bands, allocated throughout
1953-551: A wide range of interests. Many amateurs begin with a fascination with radio communication and then combine other personal interests to make pursuit of the hobby rewarding. Some of the focal areas amateurs pursue include radio contesting , radio propagation study, public service communication , technical experimentation , and computer networking . Hobbyist radio enthusiasts employ a variety of transmission methods for interaction . The primary modes for vocal communications are frequency modulation (FM) and single sideband (SSB). FM
SECTION 20
#17328688832542046-700: A year in the national capital and can be inordinately bureaucratic (for example in India) or challenging because some amateurs must undergo difficult security approval (as in Iran ). Currently, only Yemen and North Korea do not issue amateur radio licenses to their citizens. Some developing countries, especially those in Africa, Asia, and Latin America , require the payment of annual license fees that can be prohibitively expensive for most of their citizens. A few small countries may not have
2139-411: Is Nunavut , VY1 is Yukon , VY2 is Prince Edward Island , VO1 is Newfoundland , and VO2 is Labrador . CY is for amateurs operating from Sable Island (CY0) or St. Paul Island (CY9). Special permission is required to access either of these: from Parks Canada for Sable and Coast Guard for St. Paul. The last two or three letters of the call signs are typically the operator's choice (upon completing
2232-590: Is in the Turks and Caicos Islands, VP6xxx is on Pitcairn Island, VP8xxx is in the Falklands, and VP9xxx is in Bermuda. Online callbooks or call sign databases can be browsed or searched to find out who holds a specific call sign. An example of an online callbook is QRZ.com . Non-exhaustive lists of famous people who hold or have held amateur radio call signs have also been compiled and published. Many jurisdictions (but not in
2325-413: Is kept at least 100 ft above the ground over public-accessible land to avoid the possibility of exposing the public to significant electromagnetic fields. Each array is a circle 72.5 ft (22.1 m) in diameter consisting of 2,677 crossed dipole antenna elements, of which 1,792 are powered and serve as both transmitting and receiving antennas, with the rest functioning as receiving antennas. Due to
2418-508: Is no longer tested in the U.S. Once the exam is passed, the FCC issues an Amateur Radio license which is valid for ten years. Studying for the exam is made easier because the entire question pools for all license classes are posted in advance. The question pools are updated every four years by the National Conference of VECs. Prospective amateur radio operators are examined on understanding of
2511-545: Is of international concern. Both the requirements for and privileges granted to a licensee vary from country to country, but generally follow the international regulations and standards established by the International Telecommunication Union and World Radio Conferences . All countries that license citizens to use amateur radio require operators to display knowledge and understanding of key concepts, usually by passing an exam. The licenses grant hams
2604-522: Is recognized for its superior audio quality, whereas SSB is more efficient for long-range communication under limited bandwidth conditions. Radiotelegraphy using Morse code , also known as "CW" from " continuous wave ", is the wireless extension of landline (wired) telegraphy developed by Samuel Morse and dates to the earliest days of radio. Although computer-based (digital) modes and methods have largely replaced CW for commercial and military applications, many amateur radio operators still enjoy using
2697-419: Is similar to Voice over IP (VoIP), but augments two-way radio communications rather than telephone calls. EchoLink using VoIP technology has enabled amateurs to communicate through local Internet-connected repeaters and radio nodes, while IRLP has allowed the linking of repeaters to provide greater coverage area. Automatic link establishment (ALE) has enabled continuous amateur radio networks to operate on
2790-656: Is the Wireless Institute of Australia , formed in 1910; other notable societies are the Radio Society of Great Britain , the American Radio Relay League , Radio Amateurs of Canada , Bangladesh NGOs Network for Radio and Communication , the New Zealand Association of Radio Transmitters and South African Radio League . ( See Category:Amateur radio organizations ) An amateur radio operator uses
2883-684: Is typically found in the 70 cm (420–450 MHz) wavelength range, though there is also limited use on 33 cm (902–928 MHz), 23 cm (1240–1300 MHz) and shorter. These requirements also effectively limit the signal range to between 20 and 60 miles (30–100 km). Linked repeater systems, however, can allow transmissions of VHF and higher frequencies across hundreds of miles. Repeaters are usually located on heights of land or on tall structures, and allow operators to communicate over hundreds of miles using hand-held or mobile transceivers . Repeaters can also be linked together by using other amateur radio bands , landline , or
PAVE PAWS - Misplaced Pages Continue
2976-619: Is valid only in the country where it is issued or in another country that has a reciprocal licensing agreement with the issuing country. In some countries, an amateur radio license is necessary in order to purchase or possess amateur radio equipment. Amateur radio licensing in the United States exemplifies the way in which some countries award different levels of amateur radio licenses based on technical knowledge: three sequential levels of licensing exams (Technician Class, General Class, and Amateur Extra Class) are currently offered, which allow operators who pass them access to larger portions of
3069-544: The Cape Cod Missile Early Warning Station on 4 April 1981 with initial operational test and evaluation (IOT&E) completed 21 May; Beale AFB reached IOC on 15 August. The two PAVE PAWS, three BMEWS, and the PARCS & FPS-85 radar stations transferred to Strategic Air Command (then Space Command ) in 1983. By 1981 Cheyenne Mountain was providing 6,700 messages per hour including those based on input from
3162-795: The FAA restricts aircraft at altitudes below 4,500 ft (1,400 m) to maintain 1 nm (1.85 km) from the Cape Cod SSPARS phased array. On May 23, 1975 the USAF announced the Raytheon Corporation would be contracted to build the East Coast facility in Otis Air Force Base and West Coast facility in Beale Air Force Base . On October 27, 1976, ground-breaking ceremonies were held at
3255-708: The Internet . Amateur radio satellites can be accessed, some using a hand-held transceiver ( HT ), even, at times, using the factory "rubber duck" antenna. Hams also use the moon , the aurora borealis , and the ionized trails of meteors as reflectors of radio waves. Hams can also contact the International Space Station (ISS) because many astronauts are licensed as amateur radio operators. Amateur radio operators use their amateur radio station to make contacts with individual hams as well as participate in round-table discussion groups or "rag chew sessions" on
3348-530: The Internet . Amateur radio is officially represented and coordinated by the International Amateur Radio Union (IARU), which is organized in three regions and has as its members the national amateur radio societies which exist in most countries. According to an estimate made in 2011 by the American Radio Relay League (the American national amateur radio society), two million people throughout
3441-662: The Kamchatka peninsula from locations in southwestern Russia". The Safeguard PAR station that closed in 1976, had its radar "modified for the ADCOM mission during 1977 [and] ADCOM accepted [the Concrete Missile Early Warning Station] from the Army on 3 October 1977" for "SLBM surveillance of Arctic Ocean areas". By December 1977 RADC had developed the 322 watt PAVE PAWS "solid state transmitter and receiver module", and
3534-752: The Kwajalein Missile Site Radar (1967). The Avco 474N Submarine Launched Ballistic Missile (SLBM) Detection and Warning System (SLBMD&W System) was deployed as "an austere…interim line-of-sight system" after approval in July 1965 to modify some Air Defense Command (ADC) Avco AN/FPS-26 Frequency Diversity Radars into Avco AN/FSS-7 SLBM Detection Radars. The 474N sites planned for 1968 also were to include AN/GSQ-89 data processing equipment (for synthesizing tracks from radar returns), as well as site communications equipment that NORAD requested on 10 May 1965 to allow "dual full period dedicated data circuits" to
3627-649: The Project Space Track "phased-array radar at Eglin AFB …for SLBM surveillance on an "on-call" basis" "at the appropriate DEFCON ". By June 1966 the refined FPS-85 plan was for it "to have the capability to operate in the SLBM mode simultaneously [ sic ] [interlaced transmissions] with the Spacetrack surveillance and tracking modes" Rebuilding of the "separate faces for transmitting and receiving" began in 1967 after
3720-653: The Safeguard Program for defending against enemy ballistic missiles. The SLBM Phased Array Radar System (SPARS) was the USAF program initiated in November 1972 by the Joint Chiefs of Staff (JCS) while the Army's PAR was under construction. A 1974 SPARS proposal for "two new SLBM Phased Array Warning Radars" was submitted to replace the east/west coast 474N detection radars, which had "limitations against Soviet SLBMs, particularly
3813-479: The high frequency bands with global coverage. Other modes, such as FSK441 using software such as WSJT , are used for weak signal modes including meteor scatter and moonbounce communications. Fast scan amateur television has gained popularity as hobbyists adapt inexpensive consumer video electronics like camcorders and video cards in PCs . Because of the wide bandwidth and stable signals required, amateur television
PAVE PAWS - Misplaced Pages Continue
3906-444: The radio spectrum , but within these bands are allowed to transmit on any frequency using a variety of voice, text, image, and data communications modes. This enables communication across a city, region, country, continent, the world, or even into space. In many countries, amateur radio operators may also send, receive, or relay radio communications between computers or transceivers connected to secure virtual private networks on
3999-531: The "missile warning center at Cheyenne Mountain AS [which was] undergoing a $ 450 million upgrade program". Other centers receiving PAVE PAWS output were the 19xx Missile Correlation Center and 19xx Space Control Center. During the post-Cold War draw down, the Eldorado and Robins radar stations closed in 1995. By October 1999, Cape Cod and Beale radars were providing data via Jam Resistant Secure Communication (JRSC) circuits to
4092-416: The 105 ft high transmitter building, which are oriented 120° apart in azimuth. The beam from each array can be deflected up to 60° from the array's central boresight axis, allowing each array to cover an azimuth angle of 120°, thus the entire radar can cover an azimuth of 240°. The building sides are sloped at an angle of 20°, and the beam can be directed at any elevation angle between 3° and 85°. The beam
4185-457: The 1955 GE AN/FPS-17 Fixed Ground Radar and 1961 RCA AN/FPS-50 Radar Set were deployed for missile tracking, and the USAF tests of modified AN/FPS-35 mechanical radars at Virginia and Pennsylvania SAGE radar stations had "marginal ability" to detect Cape Canaveral missiles in summer 1962. A Falling Leaves mechanical radar in New Jersey built for BMEWS successfully tracked a missile during
4278-825: The 420 to 450 MHz band near AN/FPS-123 radars were notified to lower their power output to mitigate interference, and AN/FPS-123s were part of the Air Force Space Surveillance System by 2009. The Beale AN/FPS-123 was upgraded to a Raytheon AN/FPS-132 Upgraded Early Warning Radar (UEWR), circa 2012, with capabilities to operate in the Ground-based Midcourse Defense (GMD) ABM system—the Beale UEWR included Avionics, Transmit-Receive modules, Receiver Exciter / Test Target Generator, Beam Steering Generator, Signal Processor, and other changes. After additional UEWR installations for GMD at Thule Site J and
4371-649: The Amateur Radio spectrum and more desirable (shorter) call signs. An exam, authorized by the Federal Communications Commission (FCC), is required for all levels of the Amateur Radio license. These exams are administered by Volunteer Examiners, accredited by the FCC-recognized Volunteer Examiner Coordinator (VEC) system. The Technician Class and General Class exams consist of 35 multiple-choice questions, drawn randomly from
4464-577: The American coastline, while hiding the fact that it had no defensive armaments in the event an incoming missile was detected. The USAF requested the National Research Council (in May 1978) and a contractor, SRI International (April 1978), to assess PAVE PAWS radiation. Two NRC reports were prepared (1979, tbd ), SRI's Environmental Impact Statement was reviewed during a 22 January 1979 public hearing at
4557-521: The CW mode—particularly on the shortwave bands and for experimental work, such as Earth–Moon–Earth communication , because of its inherent signal-to-noise ratio advantages. Morse, using internationally agreed message encodings such as the Q code , enables communication between amateurs who speak different languages. It is also popular with homebrewers and in particular with "QRP" or very-low-power enthusiasts, as CW-only transmitters are simpler to construct, and
4650-682: The Cheyenne Mountain 425L System, which was "fully operational" on 20 April 1966. ( Cheyenne Mountain Complex relayed 474N data to " SAC , the National Military Command Center , and the Alternate NMCC over BMEWS circuits", for presentation by Display Information Processors—impact ellipses and "threat summary display" with a count of incoming missiles and "Minutes Until First Impact" countdown). By December 1965 NORAD decided to use
4743-531: The Command Center Processing and Display System in the NMCC. The transition of BMEWS and PAVE PAWS to SSPARS had begun with the 4 AN/FPS-50 BMEWS radars near Thule Air Base being replaced with a Raytheon AN/FPS-120 Solid State Phased Array Radar at Thule Site J (operational "2QFY87"). An AN/FPS-115 system was sold to Taiwan in 2000 and installed at Loshan or Leshan Mountain, Tai'an, Miaoli in 2006. It
SECTION 50
#17328688832544836-700: The East Coast Site. System performance testing at the Otis facility began on April 3, 1978 and completed by January 16, 1979. To mitigate interference at the FPS-115 site on Flatrock Hill from the Cape & Islands Emergency Medical Service (CIEMSS), on 8 February 1979 ESD installed six high pass filters—then Raytheon was contracted 24 May to move the EMS Repeater Station to Bourne, Massachusetts (completed 13 July). After
4929-637: The ITU convention for the numeral. In the United Kingdom the original calls G0xxx, G2xxx, G3xxx, G4xxx, were Full (A) License holders along with the last M0xxx full call signs issued by the City & Guilds examination authority in December 2003. Additional Full Licenses were originally granted to (B) Licenses with G1xxx, G6xxx, G7xxx, G8xxx and 1991 onward with M1xxx call signs. The newer three-level Intermediate License holders are assigned 2E0xxx and 2E1xxx, and
5022-499: The Isle of Man, "GJ" & "MJ" are Jersey and "GU" & "MU" are Guernsey. Intermediate licence call signs are slightly different. They begin 2#0 and 2#1 where the # is replaced with the country letters as above. For example "2M0" and "2M1" are Scotland, "2W0" and "2W1" are Wales and so on. The exception however is for England. The letter "E" is used, but only in intermediate-level call signs. For example "2E0" & "2E1" are used whereas
5115-587: The October 1962 Cuban Missile Crisis , and "an AN/FPS-85 long-range phased array ( Passive electronically scanned array ) radar was constructed at Eglin AFB " Site C-6, Florida beginning on 29 October 1962 (the Bendix Radio Division FPS-85 contract had been signed 2 April 1962). Early military phased array radars were also deployed for testing: Bendix AN/FPS-46 Electronically Steerable Array Radar (ESAR) at Towson, MD (powered up in November 1960), White Sands' Multi-function Array Radar (1963), and
5208-455: The Organization of American States to facilitate licensing reciprocity. When traveling abroad, visiting amateur operators must follow the rules of the country in which they wish to operate. Some countries have reciprocal international operating agreements allowing hams from other countries to operate within their borders with just their home country license. Other host countries require that
5301-612: The PARCS beginning December 1978, e.g., "extending the range" by 1989 for the Enhanced PARCS configuration (EPARCS). USAF environmental assessments in August 1975 and March 1976 for PAVE PAWS were followed by the EPA's Environmental Impact Analysis in December 1977. Environmental impacts were litigated in U.S. District Court in Boston. The government asserted the position that Pave Paws would protect
5394-649: The PAVE PAWS and the remaining FSS-7 stations. In 1981, as part of the Worldwide Military Command and Control System Information System (WIS), the Pentagon's National Military Command Center was receiving data "directly from the Satellite Early Warning System (SEWS) and directly from the PAVE PAWS sensor systems". Beam Steering Unit (BSU) and Receiver Beam Former (REX) replacements were made on
5487-575: The RF spectrum, usually allowing choice of an effective frequency for communications across a local, regional, or worldwide path. The shortwave bands, or HF , are suitable for worldwide communication, and the VHF and UHF bands normally provide local or regional communication, while the microwave bands have enough space, or bandwidth , for amateur television transmissions and high-speed computer networks . In most countries, an amateur radio license grants permission to
5580-628: The Sandwich MA high school auditorium (~300 people). The studies found no elevated cancer risk from PAVE PAWS e.g., elevated Ewing sarcoma rates were not supported by 2005 available data (a December 2007 MA Department of Health report concluded it "appears unlikely that PAVE PAWS played a primary role in the incidence of Ewing family of tumors on Cape Cod.") A followup to a 1978 Air Force School of Aerospace Medicine report concluded in 2005 that power densities beyond 15 metres (49.2 ft) were within permissible exposure limits . Consistent with other regulations to prevent interference with aircraft systems,
5673-425: The Soviet Union by the 1970s, significantly decreased the warning time available between the detection of an incoming enemy missile and its reaching its target, because SLBMs can be launched closer to the US than the previous ICBMs , which have a long flight path from the Soviet Union to the continental US. Thus there was a need for a radar system with faster reaction time than existing radars. PAVE PAWS later acquired
SECTION 60
#17328688832545766-415: The System Program Office (ESD/OCL) issued the AN/FPS-115 "System Performance Specification …SS-OCLU-75-1A" on 15 December 1977. IBM's PAVE PAWS "beam-steering and pulse schedules from the CYBER-174 " duplexed computers to the MODCOMP IV duplexed radar control computers were "based upon" PARCS program(s) installed for attack characterization in 1977 when the USAF received the Army's PAR. Bell Labs enhanced
5859-428: The UK & Europe) may issue specialty vehicle registration plates to licensed amateur radio operators. The fees for application and renewal are usually less than the standard rate for specialty plates. In most administrations, unlike other RF spectrum users, radio amateurs may build or modify transmitting equipment for their own use within the amateur spectrum without the need to obtain government certification of
5952-444: The UK (contracted 2003), a 2012 ESD/XRX Request for Information for replacement, and remote operation, of the remaining "PAVE PAWS/BMEWS/PARCS systems" at Cape Cod, Alaska, and North Dakota was issued. The Alaska AN/FPS-132 was contracted in fall 2012 and in 2013, the U.S. announced a plan to sell an AN/FPS-132 to Qatar . PAVE Too Many Requests If you report this error to the Wikimedia System Administrators, please include
6045-407: The US would consist of hundreds of ICBMs and SLBMs incoming simultaneously. The beam of the phased array radar is steered electronically without moving the fixed antenna, so it can be pointed in a different direction in milliseconds, allowing it to track many incoming missiles at the same time. The AN/FPS-115 radar consists of two phased arrays of antenna elements mounted on two sloping sides of
6138-552: The United Kingdom and Australia, have begun requiring a practical assessment in addition to the written exams in order to obtain a beginner's license, which they call a Foundation License. In most countries, an operator will be assigned a call sign with their license. In some countries, a separate "station license" is required for any station used by an amateur radio operator. Amateur radio licenses may also be granted to organizations or clubs. In some countries, hams were allowed to operate only club stations. An amateur radio license
6231-763: The air. Some join in regularly scheduled on-air meetings with other amateur radio operators, called " nets " (as in "networks"), which are moderated by a station referred to as "Net Control". Nets can allow operators to learn procedures for emergencies, be an informal round table, or cover specific interests shared by a group. Amateur radio operators, using battery- or generator-powered equipment, often provide essential communications services when regular channels are unavailable due to natural disaster or other disruptive events . Many amateur radio operators participate in radio contests, during which an individual or team of operators typically seek to contact and exchange information with as many other amateur radio stations as possible in
6324-457: The basic Foundation License holders are granted call signs M3xxx, M6xxx or M7xxx. Instead of using numbers, in the UK the second letter after the initial 'G' or 'M' identifies the station's location; for example, a call sign G7OOE becomes GM7OOE and M0RDM becomes MM0RDM when that license holder is operating a station in Scotland. Prefix "GM" & "MM" are Scotland, "GW" & "MW" are Wales, "GI" & "MI" are Northern Ireland, "GD" & "MD" are
6417-446: The call signs beginning G or M for foundation and full licenses never use the "E". In the United States, for non-vanity licenses, the numeral indicates the geographical district the holder resided in when the license was first issued. Prior to 1978, US hams were required to obtain a new call sign if they moved out of their geographic district. In Canada, call signs start with VA, VE, VY, VO, and CY. Call signs starting with 'V' end with
6510-501: The classroom to teach English, map skills, geography, math, science, and computer skills. The term "ham" was first a pejorative term used in professional wired telegraphy during the 19th century, to mock operators with poor Morse code -sending skills (" ham-fisted "). This term continued to be used after the invention of radio and the proliferation of amateur experimentation with wireless telegraphy; among land- and sea-based professional radio operators, "ham" amateurs were considered
6603-445: The computer can instantly steer the beam to a different direction. The radar operates in the UHF band between 420 - 450 MHz, which is shared with the 70 centimeter amateur band (just below the UHF television broadcast band), that is a wavelength of 71–67 cm, with circular polarization . It is an active array ( AESA ); each of the 1,792 transmitting elements has its own solid-state transmitter/receiver module, and radiates
6696-584: The details below. Request from 172.68.168.226 via cp1108 cp1108, Varnish XID 825055733 Upstream caches: cp1108 int Error: 429, Too Many Requests at Fri, 29 Nov 2024 08:28:03 GMT Amateur radio The amateur radio service ( amateur service and amateur-satellite service ) is established by the International Telecommunication Union (ITU) through the Radio Regulations . National governments regulate technical and operational characteristics of transmissions and issue individual station licenses with
6789-755: The early 20th century. The First Annual Official Wireless Blue Book of the Wireless Association of America , produced in 1909, contains a list of amateur radio stations. This radio callbook lists wireless telegraph stations in Canada and the United States, including 89 amateur radio stations. As with radio in general, amateur radio was associated with various amateur experimenters and hobbyists. Amateur radio enthusiasts have significantly contributed to science , engineering , industry, and social services . Research by amateur operators has founded new industries, built economies, empowered nations, and saved lives in times of emergency. Ham radio can also be used in
6882-408: The equipment. Licensed amateurs can also use any frequency in their bands (rather than being allocated fixed frequencies or channels) and can operate medium-to-high-powered equipment on a wide range of frequencies so long as they meet certain technical parameters including occupied bandwidth, power, and prevention of spurious emission . Radio amateurs have access to frequency allocations throughout
6975-523: The four Cape Cod and Beale radars in the 1980s. The PAVE PAWS Expansion Program had begun by February 1982 to replace "older FPS-85 and FSS-7 SLBM surveillance radars in Florida with a new PAVE PAWS radar to provide improved surveillance of possible SLBM launch areas southeast of the United States [and for another] to the Southwest." After a 3 June 1983 RFP, Raytheon Company was contracted on 10 November and had
7068-423: The help of a mentor, teacher, or friend. In North America, established amateurs who help newcomers are often referred to as "Elmers", as coined by Rodney Newkirk, W9BRD, within the ham community. In addition, many countries have national amateur radio societies which encourage newcomers and work with government communications regulation authorities for the benefit of all radio amateurs. The oldest of these societies
7161-818: The human ear-brain signal processing system can pull weak CW signals out of the noise where voice signals would be totally inaudible. A similar "legacy" mode popular with home constructors is amplitude modulation (AM), pursued by many vintage amateur radio enthusiasts and aficionados of vacuum tube technology. Demonstrating a proficiency in Morse code was for many years a requirement to obtain an amateur license to transmit on frequencies below 30 MHz. Following changes in international regulations in 2003, countries are no longer required to demand proficiency. The United States Federal Communications Commission , for example, phased out this requirement for all license classes on 23 February 2007. Modern personal computers have encouraged
7254-570: The key concepts of electronics, radio equipment, antennas, radio propagation , RF safety, and the radio regulations of the government granting the license. These examinations are sets of questions typically posed in either a short answer or multiple-choice format. Examinations can be administered by bureaucrats , non-paid certified examiners, or previously licensed amateur radio operators. The ease with which an individual can acquire an amateur radio license varies from country to country. In some countries, examinations may be offered only once or twice
7347-417: The license holder to own, modify, and operate equipment that is not certified by a governmental regulatory agency. This encourages amateur radio operators to experiment with home-constructed or modified equipment. The use of such equipment must still satisfy national and international standards on spurious emissions . Amateur radio operators are encouraged both by regulations and tradition of respectful use of
7440-571: The licensing test, the ham writes three most-preferred options). Two-letter call sign suffixes require a ham to have already been licensed for 5 years. Call signs in Canada can be requested with a fee. Also, for smaller geopolitical entities, the numeral may be part of the country identification. For example, VP2xxx is in the British West Indies, which is subdivided into VP2Exx Anguilla, VP2Mxx Montserrat, and VP2Vxx British Virgin Islands. VP5xxx
7533-602: The longer range SS-N-8 " on 1973 "Delta" class submarines . Development began in August 1973, SPARS was renamed PAVE PAWS on 18 February 1975, and system production was requested by a 13 June 1975 Request for Proposals (RFP). Rome Air Development Center (RADC) "was responsible for the design, fabrication installation, integration test, and evaluation of" PAVE PAWS through 1980. The differing USAF AN/FPS-109 Cobra Dane phased array radar in Alaska achieved IOC on 13 July 1977 for "providing intelligence on Soviet test missiles fired at
7626-493: The periphery of the contiguous United States, then two more in 1987–95 as part of the United States Space Surveillance Network . One system was sold to Taiwan and is still in service. Under the Joint Electronics Type Designation System (JETDS), all U.S. military radar and tracking systems are assigned a unique identifying alphanumeric designation. The letters “AN” (for Army-Navy) are placed ahead of
7719-432: The phenomenon of interference the radio waves from the separate elements combine in front of the antenna to form a beam. The array has a gain of 38.6 dB, and the width of the beam is only 2.2°. The drive current for each antenna element passes through a device called a phase shifter , controlled by the central computer. By changing the relative timing ( phase ) of the current pulses supplied to each antenna element
7812-892: The privilege to operate in larger segments of the radio frequency spectrum, with a wider variety of communication techniques, and with higher power levels relative to unlicensed personal radio services (such as CB radio , FRS , and PMR446 ), which require type-approved equipment restricted in mode, range, and power. Amateur licensing is a routine civil administrative matter in many countries. Amateurs therein must pass an examination to demonstrate technical knowledge, operating competence, and awareness of legal and regulatory requirements, in order to avoid interfering with other amateurs and other radio services. A series of exams are often available, each progressively more challenging and granting more privileges: greater frequency availability, higher power output, permitted experimentation, and, in some countries, distinctive call signs. Some countries, such as
7905-553: The south and together the PAVE PAWS sets would have provided Taiwan with 360-degree coverage. The radar site in Taiwan sits on top of a mountain at an elevation of over 2,600 m (8,500 ft). Due to its extremely elevated position the Taiwanese set has the unique ability to track surface ships. Detection and tracking data is believed to be shared with the United States in real time; this has not been officially confirmed. The radar site
7998-497: The spectrum to use as little power as possible to accomplish the communication. This is to minimise interference or EMC to any other device. Although allowable power levels are moderate by commercial standards, they are sufficient to enable global communication. Lower license classes usually have lower power limits; for example, the lowest license class in the UK (Foundation licence) has a limit of 10 W. Power limits vary from country to country and between license classes within
8091-582: The surveillance mode, which normally consumes about 11% of the duty cycle, the radar repeatedly scans the horizon across its full 240° azimuth in a pattern between 3° and 10° elevation, creating a "surveillance fence" to immediately detect missiles as they rise above the horizon into the radar's field of view. In the tracking mode, which normally consumes the other 7% of the 18% duty cycle, the radar beam follows already-detected objects to determine their trajectory, calculating their launch and target points. Fixed-reflector radars with mechanically-scanned beams such as
8184-615: The under-construction Eglin FPS-85 was "almost totally destroyed by fire on 5 January 1965". FPS-85 IOC was in 1969, 474N interim operations began in July 1970 (474N IOC was 5 May 1972), and in 1972 20% of Eglin FPS-85 "surveillance capability…became dedicated to search for SLBMs," and new SLBM software was installed in 1975. (the FPS-85 was expanded in 1974). The Stanley R. Mickelsen Safeguard Complex with North Dakota phased arrays (four-face Missile Site Radar and single-face GE Perimeter Acquisition Radar, PAR) became operational in 1975 as part of
8277-442: The use of digital modes such as radioteletype (RTTY) which previously required cumbersome mechanical equipment. Hams led the development of packet radio in the 1970s, which has employed protocols such as AX.25 and TCP/IP . Specialized digital modes such as PSK31 allow real-time, low-power communications on the shortwave bands but have been losing favor in place of newer digital modes such as FT8 . Radio over IP , or RoIP,
8370-506: The visiting ham apply for a formal permit, or even a new host country-issued license, in advance. The reciprocal recognition of licenses frequently not only depends on the involved licensing authorities, but also on the nationality of the bearer. As an example, in the US, foreign licenses are recognized only if the bearer does not have US citizenship and holds no US license (which may differ in terms of operating privileges and restrictions). Conversely,
8463-627: The world are regularly involved with amateur radio. About 830,000 amateur radio stations are located in IARU Region 2 (the Americas) followed by IARU Region 3 (South and East Asia and the Pacific Ocean) with about 750,000 stations. A significantly smaller number, about 400,000, are located in IARU Region 1 (Europe, Middle East, CIS , Africa). The origins of amateur radio can be traced to the late 19th century, but amateur radio as practised today began in
8556-455: Was commissioned into service in 2013. The system cost approximately US$ 1.4 billion and Raytheon was the prime contractor. It provides up to six minutes notice of Chinese ballistic missile attack. The system spends most of its time observing satellites and orbital debris; this information is shared with the United States. In 2016 Raytheon Integrated Defense Systems was awarded a $ 26.2 million contract to upgrade Taiwan's radar system. This followed on
8649-781: Was first occupied by a Naval Maritime and Surveillance Command radar surveillance facility, which was relocated to a higher peak in the same region to make way for PAVE PAWS. The Solid State Phased Array Radar System (SSPARS) began replacing PAVE PAWS when the first AN/FPS-115 face was taken off-line for the radar upgrade. New Raytheon AN/FPS-123 Early Warning Radars became operational in 19xx (Beale) and 19xx (Cape Cod) in each base's existing PAVE PAWS "Scanner Building". RAF Fylingdales , UK and Clear Space Force Station , Alaska BMEWS stations became SSPARS radar stations when their respective AN/FPS-126 radar (3 faces) and 2001 Raytheon AN/FPS-120 Solid State Phased Array Radar became operational. In 2007, 100 owners/trustees of amateur radio repeaters in
#253746