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.).
81-611: 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 a unique identifying call sign , which must be used in all transmissions. Amateur operators must hold an amateur radio license which
162-463: 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
243-575: 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
324-456: 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
405-578: 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 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
486-440: 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
567-463: 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
648-860: A country. For example, the peak envelope power limits for the highest available license classes in a few selected countries are: 2.25 kW in Canada; 1.5 kW in the United States; 1.0 kW in Belgium, Luxembourg , Switzerland, South Africa and New Zealand; 750 W in Germany; 500 W in Italy; 400 W in Australia, India, and the United Kingdom; and 150 W in Oman . Amateur-satellite service An amateur radio satellite
729-618: 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
810-560: 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
891-614: A glowbug. The majority of glowbug transmitters are designed to be used in the CW radiotelegraphy mode. A number of radio amateurs also build their own tube receivers and AM voice transmitters. As late as the 1960s, glowbugs were part of many beginner ham stations because of their simple, tube-based designs. Glowbugs are popular among QRP enthusiasts and others with a penchant for constructing their own equipment. Enthusiasts may assemble glowbugs on steel chassis, tin cakepans, and wooden boards. Glowbug enthusiasts can often be heard communicating on
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#1732772048234972-548: 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
1053-445: A minority of hams own and operate completely homebrew or kit-built amateur stations. However, there are many new ham radio kit suppliers, and the "art" of homebrewing is alive and thriving. Homebrewing differs from kit-building in that "homebrew" connotes the process of constructing equipment using parts and designs gathered from varied and often improvised sources. Even the most skilled homebrewer may not have time or resources to build
1134-457: 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
1215-431: 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
1296-472: 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
1377-407: 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
1458-515: A powerful technical mastery to hams. In 1958, a CQ editorial opined that if ham radio lost status as a technical activity, it might also lose the privilege of operating on the public airwaves, saying, ‘‘As our ranks of home constructors thin we also fall to a lower technical level as a group’’. In the 1950s and 60s, some hams turned to constructing their stations from kits sold by Heathkit , Eico , EF Johnson , Allied Radio's Knight-Kit , World Radio Laboratories and other suppliers. Today, only
1539-436: 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
1620-551: 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
1701-715: 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
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#17327720482341782-411: 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
1863-550: 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
1944-511: 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
2025-664: Is fun and gives them the satisfaction that comes from mastering electronic knowledge. QRPers are ham radio enthusiasts known to use a power output of five watts, sometimes operating with as little as 100 milliwatts or even less. Extremely low power—one watt and below—is often referred to by hobbyists as QRPp. Commercial transceivers designed to operate at or near-QRP power levels have been available for many years, but some QRPers prefer to design and build their own equipment, either from kits or from scratch. Some have built miniature transmitters and transceivers into Altoids boxes and operate using battery power. Popular QRP kit models include
2106-602: 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
2187-519: 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
2268-459: 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 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
2349-463: 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
2430-670: 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
2511-451: 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
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2592-521: 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
2673-418: 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
2754-692: 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
2835-683: 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
2916-615: 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
2997-462: The Elecraft K2, KX1, and now KX3 and those produced by NorCal, Small Wonder Labs, and others. QRP activity can often be heard on 7.030 MHz. "Glowbug" is a term used by US amateurs to describe a simple home-made tube-type radio set, reminiscent of the shortwave radio-building craze of the 1920s and 30s. Generally, any small, home-built tube-type transmitter or receiver may be referred to as
3078-665: 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
3159-481: 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
3240-450: 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
3321-589: The 435-438 MHz band is particularly popular for amateur/educational small satellites such as Cubesats. Amateur radio homebrew Homebrew is an amateur radio slang term for home-built, noncommercial radio equipment. Design and construction of equipment from first principles is valued by amateur radio hobbyists, known as "hams", for educational value, and to allow experimentation and development of techniques or levels of performance not readily available as commercial products. Some items can be home-brewed at similar or lower cost than purchased equivalents. In
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3402-686: 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
3483-524: 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
3564-472: 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
3645-478: 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"
3726-589: 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
3807-503: 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
3888-460: 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
3969-611: 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 the early 20th century. The First Annual Official Wireless Blue Book of the Wireless Association of America , produced in 1909, contains
4050-581: 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
4131-424: 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
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#17327720482344212-549: 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
4293-760: 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
4374-513: 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
4455-512: 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
4536-445: 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
4617-496: 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
4698-472: 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
4779-563: 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
4860-502: The early years of amateur radio, long before factory-built gear was easily available, hams built their own transmitting and receiving equipment, known as homebrewing. In the 1930s, 40s, and 50s, hams handcrafted reasonable-quality vacuum tube -based transmitters and receivers which were often housed in their basements, and it was common for a well-built "homebrew rig" to cover all the high frequency bands (1.8 to 30 MHz). After WWII ended, surplus material (transmitters/receivers, etc.),
4941-405: 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
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#17327720482345022-436: The equivalent of modern commercially made amateur radio gear from scratch, as the commercial units contain custom integrated circuits, custom cabinets, and are the result of multiple prototypes and exhaustive testing. However, constructing one's own equipment using relatively simple designs and easily obtainable or junk box electronic components is still possible. Homebrew enthusiasts say that building one's own radio equipment
5103-420: 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
5184-471: 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
5265-819: 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
5346-568: 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
5427-460: 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
5508-417: 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
5589-585: 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
5670-460: 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,
5751-519: 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 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
5832-888: 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
5913-473: 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,
5994-416: 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
6075-475: 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
6156-496: 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
6237-496: 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
6318-441: 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,
6399-509: 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,
6480-581: Was readily available, providing previously unavailable material at costs low enough for amateur experimental use. Homebrewing was often encouraged by amateur radio publications. In 1950, CQ Amateur Radio Magazine announced a ‘‘$ 1000 Cash Prize ‘Home Brew’ Contest’’ and called independently-built equipment ‘‘the type of gear which has helped to make amateur radio our greatest reservoir of technical proficiency.’’ The magazine tried to steer hams back into building by sponsoring such competitions and by publishing more construction plans, saying that homebrewing imparted
6561-541: 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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