Amateur radio
Encyclopedia
Amateur radio is the use of designated radio frequency
spectrum
for purposes of private recreation, non-commercial
exchange of messages, wireless
experimentation, self-training, and emergency communication. The term "amateur" is used to specify persons interested in radio technique solely with a personal aim and without pecuniary interest, 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.).
Amateur radio operation is coordinated by the International Telecommunication Union
(ITU) and licensed by the individual national governments that regulate technical and operational characteristics of transmissions and issue individual stations with an identifying call sign
. Prospective amateur operators are tested for their understanding of key concepts in electronics and the host government's radio regulations. Amateurs use a variety of voice, text, image and data communications modes and have access to frequency allocations throughout the RF spectrum to enable communication across a city, a region, a country, a continent or the whole world. An estimated two million people throughout the world are regularly involved with amateur radio.
s is contained in the First Annual Official Wireless Blue Book of the Wireless Association of America in 1909. This first radio callbook
lists wireless telegraph stations in Canada and the United States, including 89 amateur radio stations. As with radio in general, the birth of amateur radio was strongly associated with various amateur experimenters and hobbyists. Throughout its history, amateur radio enthusiasts have made significant contributions to science
, engineering
, industry
, and social services. Research by amateur radio operators has founded new industries, built economies, empowered nations, and saved lives in times of emergency.
(FM) and single sideband
(SSB). FM offers high quality audio signals, while SSB is better at long distance communication when bandwidth is restricted.
Radiotelegraphy
using Morse code
(also known as "CW" from "continuous wave
") is an activity dating to the earliest days of radio. It is the wireless extension of land line (wire based) telegraphy
developed by Samuel Morse and was the predominant real time long-distance communication method of the 19th century. Though computer-based (digital) modes and methods have largely replaced CW for commercial and military applications, many amateur radio operators still enjoy using the CW mode, particularly on the shortwave
bands and for experimental work such as earth-moon-earth communication
, with 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
as CW-only transmitters are simpler to construct. 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 amateur licenses for the high frequency
bands (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 February 23, 2007.
Modern personal computers have encouraged 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 TCP/IP since the 1980s. Specialized digital modes such as PSK31
allow real-time, low-power communications on the shortwave bands. Echolink
using Voice over IP
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 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 is typically found in the 70 cm (420 MHz–450 MHz) frequency range, though there is also limited use on 33 cm (902 MHz–928 MHz), 23 cm (1240 MHz–1300 MHz) and higher. These requirements also effectively limit the signal range to between 20 and 60 miles (30 km–100 km). The use of linked repeater
systems, however, can allow transmissions across hundreds of miles.
These repeaters, or automated relay stations, are used on VHF and higher frequencies to increase signal range. Repeaters are usually located on top of a mountain
, hill
, or tall building
and allow operators to communicate over hundreds of square miles using a low power hand-held transceiver
. Repeaters can also be linked together by use of other amateur radio bands
, landline
, or the Internet
.
Communication satellite
s called OSCAR
s (Orbiting Satellite Carrying Amateur Radio) 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 are also often able to make contact with the International Space Station
(ISS), as many astronaut
s and cosmonauts are licensed as amateur radio operators.
Amateur radio operators use their amateur radio station
to make contacts with individual hams as well as participating in round table discussion groups or "rag chew sessions" on 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 be topical, covering specific interests shared by a group.
spectrum using a wide variety of communication techniques with higher power levels permitted compared to unlicensed personal radio services such as CB radio
, Family Radio Service
or PMR446
that require type-approved equipment restricted in frequency range and power.
In many countries, amateur licensing is a routine civil administrative matter. Amateurs are required to pass an examination to demonstrate technical knowledge, operating competence and awareness of legal and regulatory requirements in order to avoid interference with other amateurs and other radio services. There are often a series of exams available, each progressively more challenging and granting more privileges in terms of frequency availability, power output, permitted experimentation, and in some countries, distinctive call signs. Some countries such as the United Kingdom
and Australia
have begun requiring a practical training course in addition to the written exams in order to obtain a beginner's license, called a Foundation License.
Amateur radio licensing in the United States
serves as an example of the way 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 the Amateur Radio spectrum and more desirable call signs.
In some countries, an amateur radio license is necessary in order to purchase or possess amateur radio equipment.
An amateur radio license is only valid in the country
in which it is issued, or in another country that has a reciprocal licensing agreement with the issuing country.
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 Telecommunications Union and World Radio Conferences
.
In most countries, an individual 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. Some countries only allow ham radio operators to operate club stations. Others, such as Syria
and Cuba
restrict all operation by foreigners to club stations only. Radio transmission permits are closely controlled by nations' governments because clandestine uses of radio can be made, and, because radio waves propagate beyond national boundaries, radio is an international matter.
, 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 bureaucrat
s, 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 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
). A handful of countries, currently only Yemen
and North Korea
, simply do not issue amateur radio licenses to their citizens, although in both cases a limited number of foreign visitors have been permitted to obtain amateur licenses in the past decade. 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 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
, Canada
, and most of the countries in Europe
, there are frequent license examinations opportunities in major cities.
The granting of a separate license to 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 require the newly-licensed individual to operate from stations licensed to a club or organization for a period of time before a higher class of license can be acquired.
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 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 only recognized if the bearer does not have US citizenship and holds no US license (which may differ in terms of operating privileges and restrictions). Conversely, a US citizen may operate under reciprocal agreements in Canada, but not a non-US citizen holding a US license.
, formed in 1910; other notable societies are the Radio Society of Great Britain
, the American Radio Relay League
, Radio Amateurs of Canada
, the New Zealand Association of Radio Transmitters
and South African Radio League
. (See :Category:Amateur radio organizations)
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 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 in respect of (B) Licensees with G1xxx, G6xxx, G7xxx, G8xxx and 1991 onward with M1xxx calls. The newer three level Intermediate licensees are 2E1xxx and 2E0xx and basic Foundation license holders are granted M3xxx, M6xxx call signs. In the United States
, for non-Vanity licenses, the numeral indicates the geographical district the holder resided in when the license was issued. Prior to 1978, US hams were required to obtain a new call sign if they moved out of their geographic district.
Also, for smaller entities, a numeral may be part of the country identification. For example, VP2xxx is in the British West Indies (subdivided into VP2Exx Anguilla, VP2Mxx Montserrat, and VP2Vxx British Virgin Islands), VP5xxx is in the Turks and Caicos Islands, VP6xxx is on Pitcairn Island, VP8xxx is in the Falklands, and VP9xxx is in Bermuda.
Online callbook
s or callsign databases can be browsed or searched to find out who holds a specific callsign. Non-exhaustive lists of famous people who hold or have held amateur radio callsigns have also been compiled and published.
Many jurisdictions issue specialty vehicle registration plate
s to licensed amateur radio operators often in order to facilitate their movement during an emergency. The fees for application and renewal are usually less than the standard rate for specialty plates.
.
Radio amateurs have access to frequency allocations throughout 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 network
s.
In most countries, an amateur radio license grants permission to 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 emission
s.
The amount of output power
an amateur radio licensee may legally use varies from country to country. Although allowable power
levels are moderate by commercial standards, they are sufficient to enable global communication. Power limits vary from country to country and between license classes within 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
, was 2 kW in the former Yugoslavia
, 1.5 kW in the United States
, 1 kW in Belgium
and Switzerland
, 750 W in Germany
, 500 W in Italy
, 400 W in Australia
, India
and the United Kingdom
, and 150 W in Oman
. Lower license classes usually have lower power limits; for example, the lowest license class in the UK has a limit of 10 W. Amateur radio operators are encouraged both by regulations and tradition of respectful use of the spectrum to use as little power as possible to accomplish the communication.
Output power may also depend on the mode of transmission. In Australia, for example, although 400w Peak Envelope Power may be used for SSB transmissions, FM and other modes are limited to 120 watts.
(ITU) governs the allocation of communications frequencies worldwide, with participation by each nation's communications regulation authority. National communications regulators have some liberty to restrict access to these bandplan
frequencies or to award additional allocations as long as radio services in other countries do not suffer interference. In some countries, specific emission types
are restricted to certain parts of the radio spectrum, and in most other countries, International Amateur Radio Union
(IARU) member societies adopt voluntary plans to ensure the most effective use of spectrum.
In a few cases, a national telecommunication agency may also allow hams to use frequencies outside of the internationally allocated amateur radio bands. In Trinidad and Tobago
, hams are allowed to use a repeater which is located on 148.800 MHz. This repeater is used and maintained by the National Emergency Management Agency (NEMA), but may be used by radio amateurs in times of emergency or during normal times to test their capability and conduct emergency drills. This repeater can also be used by non-ham NEMA staff and REACT members. In Australia and New Zealand ham operators are authorized to use one of the UHF TV channels. In the U.S., in cases of emergency, amateur radio operators providing essential communication needs in connection with the immediate safety of human life and immediate protection of property when normal communication systems are not available may use any frequency including those of other radio services such as police and fire communications and the Alaska
statewide emergency frequency of 5167.5 kHz.
Similarly, amateurs in the United States may apply to be registered with the Military Auxiliary Radio System (MARS). Once approved and trained, these amateurs also operate on US government military frequencies to provide contingency communications and morale message traffic support to the military services.
, for example, is not generally permitted in the Amateur Radio service except for the special purpose of satellite vehicle control uplinks. The following is a partial list of the modes of communication used, where the mode includes both modulation
types and operating protocols.
(AM), frequency modulation
(FM), or single-sideband modulation
(SSB).
Radio frequency
Radio frequency is a rate of oscillation in the range of about 3 kHz to 300 GHz, which corresponds to the frequency of radio waves, and the alternating currents which carry radio signals...
spectrum
Radio spectrum
Radio spectrum refers to the part of the electromagnetic spectrum corresponding to radio frequencies – that is, frequencies lower than around 300 GHz ....
for purposes of private recreation, non-commercial
Non-commercial
Non-commercial refers to an activity or entity that does not in some sense involve commerce, at least relative to similar activities that do have a commercial objective or emphasis...
exchange of messages, wireless
Wireless
Wireless telecommunications is the transfer of information between two or more points that are not physically connected. Distances can be short, such as a few meters for television remote control, or as far as thousands or even millions of kilometers for deep-space radio communications...
experimentation, self-training, and emergency communication. The term "amateur" is used to specify persons interested in radio technique solely with a personal aim and without pecuniary interest, and to differentiate it from commercial broadcasting
Commercial broadcasting
Commercial broadcasting is the broadcasting of television programs and radio programming by privately owned corporate media, as opposed to state sponsorship...
, public safety (such as police and fire) or professional two-way radio
Two-way radio
A two-way radio is a radio that can both transmit and receive , unlike a broadcast receiver which only receives content. The term refers to a personal radio transceiver that allows the operator to have a two-way conversation with other similar radios operating on the same radio frequency...
services (such as maritime, aviation, taxis, etc.).
Amateur radio operation is coordinated by the International Telecommunication Union
International Telecommunication Union
The International Telecommunication Union is the specialized agency of the United Nations which is responsible for information and communication technologies...
(ITU) and licensed by the individual national governments that regulate technical and operational characteristics of transmissions and issue individual stations with an identifying call sign
Call sign
In broadcasting and radio communications, a call sign is a unique designation for a transmitting station. In North America they are used as names for broadcasting stations...
. Prospective amateur operators are tested for their understanding of key concepts in electronics and the host government's radio regulations. Amateurs use a variety of voice, text, image and data communications modes and have access to frequency allocations throughout the RF spectrum to enable communication across a city, a region, a country, a continent or the whole world. An estimated two million people throughout the world are regularly involved with amateur radio.
History
The origins of amateur radio can be traced to the late 19th century though amateur radio, as practiced today, did not begin until the early 20th century. The first listing of amateur radio communications receiverCommunications receiver
A communications receiver is a type of radio receiver used as a component of a radio communication link.-Features:Commercial communications receivers are characterised by high stability and reliability of performance, and are generally adapted for remote control and monitoring...
s is contained in the First Annual Official Wireless Blue Book of the Wireless Association of America in 1909. This first radio callbook
Callbook
A callbook is a directory of radio station call signs. Originally a bound book that resembled a telephone directory, it contains the name and addressees of licensed radio stations in a given jurisdiction . Modern Electrics published the first callbook in the United States in 1909...
lists wireless telegraph stations in Canada and the United States, including 89 amateur radio stations. As with radio in general, the birth of amateur radio was strongly associated with various amateur experimenters and hobbyists. Throughout its history, amateur radio enthusiasts have made significant contributions to science
Science
Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe...
, engineering
Engineering
Engineering is the discipline, art, skill and profession of acquiring and applying scientific, mathematical, economic, social, and practical knowledge, in order to design and build structures, machines, devices, systems, materials and processes that safely realize improvements to the lives of...
, industry
Industry
Industry refers to the production of an economic good or service within an economy.-Industrial sectors:There are four key industrial economic sectors: the primary sector, largely raw material extraction industries such as mining and farming; the secondary sector, involving refining, construction,...
, and social services. Research by amateur radio operators has founded new industries, built economies, empowered nations, and saved lives in times of emergency.
Activities and practices
Amateur radio operators use various modes of transmission to communicate. The two most common modes for voice transmissions are frequency modulationFrequency modulation
In telecommunications and signal processing, frequency modulation conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant...
(FM) and single sideband
Single-sideband modulation
Single-sideband modulation or Single-sideband suppressed-carrier is a refinement of amplitude modulation that more efficiently uses electrical power and bandwidth....
(SSB). FM offers high quality audio signals, while SSB is better at long distance communication when bandwidth is restricted.
Radiotelegraphy
Telegraphy
Telegraphy is the long-distance transmission of messages via some form of signalling technology. Telegraphy requires messages to be converted to a code which is known to both sender and receiver...
using Morse code
Morse code
Morse code is a method of transmitting textual information as a series of on-off tones, lights, or clicks that can be directly understood by a skilled listener or observer without special equipment...
(also known as "CW" from "continuous wave
Continuous wave
A continuous wave or continuous waveform is an electromagnetic wave of constant amplitude and frequency; and in mathematical analysis, of infinite duration. Continuous wave is also the name given to an early method of radio transmission, in which a carrier wave is switched on and off...
") is an activity dating to the earliest days of radio. It is the wireless extension of land line (wire based) telegraphy
Telegraphy
Telegraphy is the long-distance transmission of messages via some form of signalling technology. Telegraphy requires messages to be converted to a code which is known to both sender and receiver...
developed by Samuel Morse and was the predominant real time long-distance communication method of the 19th century. Though computer-based (digital) modes and methods have largely replaced CW for commercial and military applications, many amateur radio operators still enjoy using the CW mode, particularly on the shortwave
Shortwave
Shortwave radio refers to the upper MF and all of the HF portion of the radio spectrum, between 1,800–30,000 kHz. Shortwave radio received its name because the wavelengths in this band are shorter than 200 m which marked the original upper limit of the medium frequency band first used...
bands and for experimental work such as earth-moon-earth communication
EME (communications)
Earth-Moon-Earth, also known as moon bounce, is a radio communications technique which relies on the propagation of radio waves from an Earth-based transmitter directed via reflection from the surface of the Moon back to an Earth-based receiver....
, with its inherent signal-to-noise ratio
Signal-to-noise ratio
Signal-to-noise ratio is a measure used in science and engineering that compares the level of a desired signal to the level of background noise. It is defined as the ratio of signal power to the noise power. A ratio higher than 1:1 indicates more signal than noise...
advantages. Morse, using internationally agreed message encodings such as the Q code
Q code
The Q code is a standardized collection of three-letter message encodings, also known as a brevity code, all of which start with the letter "Q", initially developed for commercial radiotelegraph communication, and later adopted by other radio services, especially amateur radio...
, enables communication between amateurs who speak different languages. It is also popular with homebrewers
Amateur radio homebrew
-History:In the early years of amateur radio, long before factory-built gear was easily available, most hams built their own transmitting and receiving equipment, a process that came to be known as "homebrewing." In the 1930s, 40s, and 50s, hams handcrafted reasonable-quality vacuum tube-based...
as CW-only transmitters are simpler to construct. A similar "legacy" mode popular with home constructors is amplitude modulation
Amplitude modulation
Amplitude modulation is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. AM works by varying the strength of the transmitted signal in relation to the information being sent...
(AM), pursued by many vintage amateur radio
Vintage amateur radio
Vintage amateur radio is a subset of the amateur radio hobby, considered a form of nostalgia much like antique car collecting, where enthusiasts collect, restore, preserve, build, and operate amateur radio equipment from bygone years, most notably those using vacuum tube technology.Popular modes of...
enthusiasts and aficionados of vacuum tube
Vacuum tube
In electronics, a vacuum tube, electron tube , or thermionic valve , reduced to simply "tube" or "valve" in everyday parlance, is a device that relies on the flow of electric current through a vacuum...
technology.
Demonstrating a proficiency in Morse code was for many years a requirement to obtain amateur licenses for the high frequency
High frequency
High frequency radio frequencies are between 3 and 30 MHz. Also known as the decameter band or decameter wave as the wavelengths range from one to ten decameters . Frequencies immediately below HF are denoted Medium-frequency , and the next higher frequencies are known as Very high frequency...
bands (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
Federal Communications Commission
The Federal Communications Commission is an independent agency of the United States government, created, Congressional statute , and with the majority of its commissioners appointed by the current President. The FCC works towards six goals in the areas of broadband, competition, the spectrum, the...
, for example, phased out this requirement for all license classes on February 23, 2007.
Modern personal computers have encouraged the use of digital
Digital
A digital system is a data technology that uses discrete values. By contrast, non-digital systems use a continuous range of values to represent information...
modes such as radioteletype
Radioteletype
Radioteletype is a telecommunications system consisting originally of two or more electromechanical teleprinters in different locations, later superseded by personal computers running software to emulate teleprinters, connected by radio rather than a wired link.The term radioteletype is used to...
(RTTY) which previously required cumbersome mechanical equipment. Hams led the development of packet radio
Packet radio
Packet radio is a form of packet switching technology used to transmit digital data via radio or wireless communications links. It uses the same concepts of data transmission via Datagram that are fundamental to communications via the Internet, as opposed to the older techniques used by dedicated...
in the 1970s, which has employed protocols such as TCP/IP since the 1980s. Specialized digital modes such as PSK31
PSK31
PSK31 or "Phase Shift Keying, 31 Baud" is a digital radio modulation mode, used primarily in the amateur radio field to conduct real-time keyboard-to-keyboard informal text chat between amateur radio operators.- History :...
allow real-time, low-power communications on the shortwave bands. Echolink
Echolink
EchoLink is a free computer-based Amateur Radio system that allows radio amateurs to communicate with other amateur radio operators using Voice over IP technology on the Internet for at least part of the path between them...
using Voice over IP
Voice over IP
Voice over Internet Protocol is a family of technologies, methodologies, communication protocols, and transmission techniques for the delivery of voice communications and multimedia sessions over Internet Protocol networks, such as the Internet...
technology has enabled amateurs to communicate through local Internet-connected repeaters and radio nodes, while IRLP
Internet Radio Linking Project
The Internet Radio Linking Project, also called IRLP, is a project that links amateur radio stations around the world by using Voice over IP . Each gateway consists of a dedicated computer running custom software that is connected to both a radio and the Internet. This arrangement forms what is...
has allowed the linking of repeaters to provide greater coverage area. Automatic link establishment
Automatic link establishment
Automatic Link Establishment, commonly known as ALE, is the worldwide de facto standard for digitally initiating and sustaining HF radio communications. ALE is a feature in an HF communications radio transceiver system, that enables the radio station to make contact, or initiate a circuit, between...
(ALE) has enabled continuous amateur radio networks to operate on the high frequency
High frequency
High frequency radio frequencies are between 3 and 30 MHz. Also known as the decameter band or decameter wave as the wavelengths range from one to ten decameters . Frequencies immediately below HF are denoted Medium-frequency , and the next higher frequencies are known as Very high frequency...
bands with global coverage. Other modes, such as FSK441 using software such as WSJT
WSJT (Amateur radio software)
WSJT is a computer program used for weak-signal radio communication between amateur radio operators. The program was initially written by Joe Taylor, K1JT, but is now open source and is developed by a small team...
, are used for weak signal modes including meteor scatter and moonbounce
EME (communications)
Earth-Moon-Earth, also known as moon bounce, is a radio communications technique which relies on the propagation of radio waves from an Earth-based transmitter directed via reflection from the surface of the Moon back to an Earth-based receiver....
communications.
Fast scan amateur television
Amateur television
Amateur television is the transmission of Broadcast quality video and audio over the wide range of frequencies of allocated for Radio amateur use. ATV is used for non-commercial experimentation, pleasure and public service events...
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 is typically found in the 70 cm (420 MHz–450 MHz) frequency range, though there is also limited use on 33 cm (902 MHz–928 MHz), 23 cm (1240 MHz–1300 MHz) and higher. These requirements also effectively limit the signal range to between 20 and 60 miles (30 km–100 km). The use of linked repeater
Amateur radio repeater
An amateur radio repeater is an electronic device that receives a weak or low-level amateur radio signal and retransmits it at a higher level or higher power, so that the signal can cover longer distances without degradation...
systems, however, can allow transmissions across hundreds of miles.
These repeaters, or automated relay stations, are used on VHF and higher frequencies to increase signal range. Repeaters are usually located on top of a mountain
Mountain
Image:Himalaya_annotated.jpg|thumb|right|The Himalayan mountain range with Mount Everestrect 58 14 160 49 Chomo Lonzorect 200 28 335 52 Makalurect 378 24 566 45 Mount Everestrect 188 581 920 656 Tibetan Plateaurect 250 406 340 427 Rong River...
, hill
Hill
A hill is a landform that extends above the surrounding terrain. Hills often have a distinct summit, although in areas with scarp/dip topography a hill may refer to a particular section of flat terrain without a massive summit A hill is a landform that extends above the surrounding terrain. Hills...
, or tall building
Building
In architecture, construction, engineering, real estate development and technology the word building may refer to one of the following:...
and allow operators to communicate over hundreds of square miles using a low power hand-held transceiver
Transceiver
A transceiver is a device comprising both a transmitter and a receiver which are combined and share common circuitry or a single housing. When no circuitry is common between transmit and receive functions, the device is a transmitter-receiver. The term originated in the early 1920s...
. Repeaters can also be linked together by use of other amateur radio bands
Amateur radio frequency allocations
Amateur radio frequency allocation is done by national telecommunications authorities. Globally, the International Telecommunication Union oversees how much radio spectrum is set aside for amateur radio transmissions...
, landline
Landline
A landline was originally an overland telegraph wire, as opposed to an undersea cable. Currently, landline refers to a telephone line which travels through a solid medium, either metal wire or optical fibre, as distinguished from a mobile cellular line, where transmission is via radio waves...
, or the Internet
Internet Radio Linking Project
The Internet Radio Linking Project, also called IRLP, is a project that links amateur radio stations around the world by using Voice over IP . Each gateway consists of a dedicated computer running custom software that is connected to both a radio and the Internet. This arrangement forms what is...
.
Communication satellite
Satellite
In the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavour. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon....
s called OSCAR
OSCAR
OSCAR is an acronym for Orbiting Satellite Carrying Amateur Radio. OSCAR series satellites use amateur radio frequencies to facilitate communication between amateur radio stations. These satellites can be used for free by licensed amateur radio operators for voice and data communications...
s (Orbiting Satellite Carrying Amateur Radio) can be accessed, some using a hand-held transceiver (HT
Walkie-talkie
A walkie-talkie is a hand-held, portable, two-way radio transceiver. Its development during the Second World War has been variously credited to Donald L. Hings, radio engineer Alfred J. Gross, and engineering teams at Motorola...
), even, at times, using the factory "rubber duck" antenna. Hams also use the moon
EME (communications)
Earth-Moon-Earth, also known as moon bounce, is a radio communications technique which relies on the propagation of radio waves from an Earth-based transmitter directed via reflection from the surface of the Moon back to an Earth-based receiver....
, the aurora borealis, and the ionized trails of meteors as reflectors of radio waves. Hams are also often able to make contact with the International Space Station
International Space Station
The International Space Station is a habitable, artificial satellite in low Earth orbit. The ISS follows the Salyut, Almaz, Cosmos, Skylab, and Mir space stations, as the 11th space station launched, not including the Genesis I and II prototypes...
(ISS), as many astronaut
Astronaut
An astronaut or cosmonaut is a person trained by a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft....
s and cosmonauts are licensed as amateur radio operators.
Amateur radio operators use their amateur radio station
Amateur radio station
An amateur radio station is an installation designed to provide radiocommunications in the amateur radio service for an amateur radio operator. Radio amateurs build and operate several types of amateur radio stations, including fixed ground stations, mobile stations, space stations, and temporary...
to make contacts with individual hams as well as participating in round table discussion groups or "rag chew sessions" on the air. Some join in regularly scheduled on-air meetings with other amateur radio operators, called "nets"
Amateur radio net
An amateur radio net, or simply ham net, is an gathering of amateur radio operators. Most nets convene on a regular schedule and specific frequency, and are organized for a particular purpose, such as relaying messages, discussing a common topic of interest, in severe weather , emergencies, or...
(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 be topical, covering specific interests shared by a group.
Licensing
In all countries that license citizens to use amateur radio, operators are required to display knowledge and understanding of key concepts. This is usually done by passing an exam; however some authorities also recognize certain educational or professional qualifications (such as a degree in electrical engineering) in lieu. In response, hams are granted operating privileges in larger segments of the radio frequencyRadio frequency
Radio frequency is a rate of oscillation in the range of about 3 kHz to 300 GHz, which corresponds to the frequency of radio waves, and the alternating currents which carry radio signals...
spectrum using a wide variety of communication techniques with higher power levels permitted compared to unlicensed personal radio services such as CB radio
Citizens' band radio
Citizens' Band radio is, in many countries, a system of short-distance radio communications between individuals on a selection of 40 channels within the 27-MHz band. Citizens' Band is distinct from the FRS, GMRS, MURS and amateur radio...
, Family Radio Service
Family Radio Service
The Family Radio Service is an improved walkie talkie radio system authorized in the United States since 1996. This personal radio service uses channelized frequencies in the ultra high frequency band. It does not suffer the interference effects found on citizens' band at 27 MHz, or the...
or PMR446
PMR446
PMR446 is a part of the UHF radio frequency range that is open without licensing for personal usage in most countries of the European Union. It has roughly the same use as FRS or GMRS in the United States and Canada. Depending on surrounding terrain range can vary from a few hundred metres to a...
that require type-approved equipment restricted in frequency range and power.
In many countries, amateur licensing is a routine civil administrative matter. Amateurs are required to pass an examination to demonstrate technical knowledge, operating competence and awareness of legal and regulatory requirements in order to avoid interference with other amateurs and other radio services. There are often a series of exams available, each progressively more challenging and granting more privileges in terms of frequency availability, power output, permitted experimentation, and in some countries, distinctive call signs. Some countries such as the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
and Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
have begun requiring a practical training course in addition to the written exams in order to obtain a beginner's license, called a Foundation License.
Amateur radio licensing in the United States
Amateur radio licensing in the United States
In the United States, amateur radio licensing is governed by the Federal Communications Commission under strict federal regulations. Licenses to operate amateur stations for personal use are granted to individuals of any age once they demonstrate an understanding of both pertinent FCC regulations...
serves as an example of the way 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 the Amateur Radio spectrum and more desirable call signs.
In some countries, an amateur radio license is necessary in order to purchase or possess amateur radio equipment.
An amateur radio license is only valid in the country
Country
A country is a region legally identified as a distinct entity in political geography. A country may be an independent sovereign state or one that is occupied by another state, as a non-sovereign or formerly sovereign political division, or a geographic region associated with a previously...
in which it is issued, or in another country that has a reciprocal licensing agreement with the issuing country.
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 Telecommunications Union and World Radio Conferences
World Administrative Radio Conference
The World Administrative Radio Conference was a technical conference of the International Telecommunications Union where delegates from member nations of the ITU met to revise or amend the entire international Radio Regulations pertaining to all telecommunication services throughout the world...
.
In most countries, an individual will be assigned a call sign
Call sign
In broadcasting and radio communications, a call sign is a unique designation for a transmitting station. In North America they are used as names for broadcasting stations...
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. Some countries only allow ham radio operators to operate club stations. Others, such as Syria
Syria
Syria , officially the Syrian Arab Republic , is a country in Western Asia, bordering Lebanon and the Mediterranean Sea to the West, Turkey to the north, Iraq to the east, Jordan to the south, and Israel to the southwest....
and Cuba
Cuba
The Republic of Cuba is an island nation in the Caribbean. The nation of Cuba consists of the main island of Cuba, the Isla de la Juventud, and several archipelagos. Havana is the largest city in Cuba and the country's capital. Santiago de Cuba is the second largest city...
restrict all operation by foreigners to club stations only. Radio transmission permits are closely controlled by nations' governments because clandestine uses of radio can be made, and, because radio waves propagate beyond national boundaries, radio is an international matter.
Licensing requirements
Prospective amateur radio operators are examined on understanding of the key concepts of electronics, radio equipment, antennasAntenna (radio)
An antenna is an electrical device which converts electric currents into radio waves, and vice versa. It is usually used with a radio transmitter or radio receiver...
, radio propagation
Radio propagation
Radio propagation is the behavior of radio waves when they are transmitted, or propagated from one point on the Earth to another, or into various parts of the atmosphere...
, RF
Radio frequency
Radio frequency is a rate of oscillation in the range of about 3 kHz to 300 GHz, which corresponds to the frequency of radio waves, and the alternating currents which carry radio signals...
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 bureaucrat
Bureaucrat
A bureaucrat is a member of a bureaucracy and can comprise the administration of any organization of any size, though the term usually connotes someone within an institution of a government or corporation...
s, 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 a year in the national capital, and can be inordinately bureaucratic (for example in India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
) or challenging because some amateurs must undergo difficult security approval (as in Iran
Iran
Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia...
). A handful of countries, currently only Yemen
Yemen
The Republic of Yemen , commonly known as Yemen , is a country located in the Middle East, occupying the southwestern to southern end of the Arabian Peninsula. It is bordered by Saudi Arabia to the north, the Red Sea to the west, and Oman to the east....
and North Korea
North Korea
The Democratic People’s Republic of Korea , , is a country in East Asia, occupying the northern half of the Korean Peninsula. Its capital and largest city is Pyongyang. The Korean Demilitarized Zone serves as the buffer zone between North Korea and South Korea...
, simply do not issue amateur radio licenses to their citizens, although in both cases a limited number of foreign visitors have been permitted to obtain amateur licenses in the past decade. Some developing countries, especially those in Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
, Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
, and Latin America
Latin America
Latin America is a region of the Americas where Romance languages – particularly Spanish and Portuguese, and variably French – are primarily spoken. Latin America has an area of approximately 21,069,500 km² , almost 3.9% of the Earth's surface or 14.1% of its land surface area...
, require the payment of annual license fees that can be prohibitively expensive for most of their citizens. A few small countries may not have 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
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
, the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, and most of the countries in Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
, there are frequent license examinations opportunities in major cities.
The granting of a separate license to 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 require the newly-licensed individual to operate from stations licensed to a club or organization for a period of time before a higher class of license can be acquired.
Reciprocal licensing
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 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.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
Amateur radio international operation
Amateur radio international reciprocal operating agreements permit Amateur Radio Operators from one country to operate a station whilst traveling in another without the need to obtain additional licenses or permits....
agreements allowing hams from other countries to operate within their borders with just their home country license. Other host countries require that 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 only recognized if the bearer does not have US citizenship and holds no US license (which may differ in terms of operating privileges and restrictions). Conversely, a US citizen may operate under reciprocal agreements in Canada, but not a non-US citizen holding a US license.
Newcomers
Many people start their involvement in amateur radio 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 the help of a mentor, teacher, or friend. Established amateurs who help newcomers are often referred to as "Elmers" 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 is the Wireless Institute of AustraliaWireless Institute of Australia
The Wireless Institute of Australia was formed in 1910, and is the first and oldest national amateur radio society in the world. 2010 is the 100th anniversary of its formation...
, formed in 1910; other notable societies are the Radio Society of Great Britain
Radio Society of Great Britain
First founded in 1913 as the London Wireless Club, the Radio Society of Great Britain is the United Kingdom's recognised national society for amateur radio operators. The society's patron is Prince Philip, Duke of Edinburgh and it represents the interests of the UK’s 60,000 licensed radio amateurs...
, the American Radio Relay League
American Radio Relay League
The American Radio Relay League is the largest membership association of amateur radio enthusiasts in the USA. ARRL is a non-profit organization, and was founded in May 1914 by Hiram Percy Maxim of Hartford, Connecticut...
, Radio Amateurs of Canada
Radio Amateurs of Canada
Radio Amateurs of Canada , known in French as Radio Amateurs du Canada, is a member-based, non-profit organization of amateur radio enthusiasts in Canada...
, the New Zealand Association of Radio Transmitters
New Zealand Association of Radio Transmitters
The New Zealand Association of Radio Transmitters, or NZART, is a non-profit organization of amateur radio enthusiasts in New Zealand. NZART represents New Zealand amateur radio operators nationally and internationally. NZART is a founding member of the International Amateur Radio Union...
and South African Radio League
South African Radio League
The South African Radio League , formerly known as the South African Radio Relay League , is a non-profit organization representing the interests of amateur radio enthusiasts in South Africa...
. (See :Category:Amateur radio organizations)
Call signs
An amateur radio operator uses 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, such as the U.S., require that a fee be paid 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.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:
- ZS – Shows the country from which the call sign originates and may also indicate the license class. (This call sign is licensed in South Africa, and is CEPT Class 1. Where specific classes of amateur radio license exist, the call signs may be assigned by class, but the specifics vary by issuing country.)
- 1 – Gives the subdivision of the country or territory indicated in the first part (this one refers to the Western Cape).
- NAT – The final part is unique to the holder of the license, identifying that station specifically.
Many countries do not follow the ITU convention for the numeral. In the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
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 in respect of (B) Licensees with G1xxx, G6xxx, G7xxx, G8xxx and 1991 onward with M1xxx calls. The newer three level Intermediate licensees are 2E1xxx and 2E0xx and basic Foundation license holders are granted M3xxx, M6xxx call signs. In the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, for non-Vanity licenses, the numeral indicates the geographical district the holder resided in when the license was issued. Prior to 1978, US hams were required to obtain a new call sign if they moved out of their geographic district.
Also, for smaller entities, a numeral may be part of the country identification. For example, VP2xxx is in the British West Indies (subdivided into VP2Exx Anguilla, VP2Mxx Montserrat, and VP2Vxx British Virgin Islands), VP5xxx is in the Turks and Caicos Islands, VP6xxx is on Pitcairn Island, VP8xxx is in the Falklands, and VP9xxx is in Bermuda.
Online callbook
Callbook
A callbook is a directory of radio station call signs. Originally a bound book that resembled a telephone directory, it contains the name and addressees of licensed radio stations in a given jurisdiction . Modern Electrics published the first callbook in the United States in 1909...
s or callsign databases can be browsed or searched to find out who holds a specific callsign. Non-exhaustive lists of famous people who hold or have held amateur radio callsigns have also been compiled and published.
Many jurisdictions issue specialty vehicle registration plate
Vehicle registration plate
A vehicle registration plate is a metal or plastic plate attached to a motor vehicle or trailer for official identification purposes. The registration identifier is a numeric or alphanumeric code that uniquely identifies the vehicle within the issuing region's database...
s to licensed amateur radio operators often in order to facilitate their movement during an emergency. The fees for application and renewal are usually less than the standard rate for specialty plates.
Privileges
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 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 maintenance of spurious emissionSpurious emission
A spurious emission is any radio frequency not deliberately created or transmitted, especially in a device which normally does create other frequencies...
.
Radio amateurs have access to frequency allocations throughout the RF spectrum, usually allowing choice of an effective frequency for communications across a local, regional, or worldwide path. The shortwave bands, or HF
High frequency
High frequency radio frequencies are between 3 and 30 MHz. Also known as the decameter band or decameter wave as the wavelengths range from one to ten decameters . Frequencies immediately below HF are denoted Medium-frequency , and the next higher frequencies are known as Very high frequency...
, are suitable for worldwide communication, and the VHF and UHF
Ultra high frequency
Ultra-High Frequency designates the ITU Radio frequency range of electromagnetic waves between 300 MHz and 3 GHz , also known as the decimetre band or decimetre wave as the wavelengths range from one to ten decimetres...
bands normally provide local or regional communication, while the microwave
Microwave
Microwaves, a subset of radio waves, have wavelengths ranging from as long as one meter to as short as one millimeter, or equivalently, with frequencies between 300 MHz and 300 GHz. This broad definition includes both UHF and EHF , and various sources use different boundaries...
bands have enough space, or bandwidth, for amateur television
Amateur television
Amateur television is the transmission of Broadcast quality video and audio over the wide range of frequencies of allocated for Radio amateur use. ATV is used for non-commercial experimentation, pleasure and public service events...
transmissions and high-speed computer network
Computer network
A computer network, often simply referred to as a network, is a collection of hardware components and computers interconnected by communication channels that allow sharing of resources and information....
s.
Spurious emission
A spurious emission is any radio frequency not deliberately created or transmitted, especially in a device which normally does create other frequencies...
s.
The amount of output power
Power (physics)
In physics, power is the rate at which energy is transferred, used, or transformed. For example, the rate at which a light bulb transforms electrical energy into heat and light is measured in watts—the more wattage, the more power, or equivalently the more electrical energy is used per unit...
an amateur radio licensee may legally use varies from country to country. Although allowable power
Power (physics)
In physics, power is the rate at which energy is transferred, used, or transformed. For example, the rate at which a light bulb transforms electrical energy into heat and light is measured in watts—the more wattage, the more power, or equivalently the more electrical energy is used per unit...
levels are moderate by commercial standards, they are sufficient to enable global communication. Power limits vary from country to country and between license classes within a country. For example, the peak envelope power
Peak envelope power
Peak envelope power is the average power supplied to the antenna transmission line by a transmitter during one radio frequency cycle at the crest of the modulation envelope, under normal operating conditions. The United States Federal Communications Commission uses PEP to set maximum power...
limits for the highest available license classes in a few selected countries are: 2.25 kW
Watt
The watt is a derived unit of power in the International System of Units , named after the Scottish engineer James Watt . The unit, defined as one joule per second, measures the rate of energy conversion.-Definition:...
in Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, was 2 kW in the former Yugoslavia
Yugoslavia
Yugoslavia refers to three political entities that existed successively on the western part of the Balkans during most of the 20th century....
, 1.5 kW in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, 1 kW in Belgium
Belgium
Belgium , officially the Kingdom of Belgium, is a federal state in Western Europe. It is a founding member of the European Union and hosts the EU's headquarters, and those of several other major international organisations such as NATO.Belgium is also a member of, or affiliated to, many...
and Switzerland
Switzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....
, 750 W in Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
, 500 W in Italy
Italy
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...
, 400 W in Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
and the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
, and 150 W in Oman
Oman
Oman , officially called the Sultanate of Oman , is an Arab state in southwest Asia on the southeast coast of the Arabian Peninsula. It is bordered by the United Arab Emirates to the northwest, Saudi Arabia to the west, and Yemen to the southwest. The coast is formed by the Arabian Sea on the...
. Lower license classes usually have lower power limits; for example, the lowest license class in the UK has a limit of 10 W. Amateur radio operators are encouraged both by regulations and tradition of respectful use of the spectrum to use as little power as possible to accomplish the communication.
Output power may also depend on the mode of transmission. In Australia, for example, although 400w Peak Envelope Power may be used for SSB transmissions, FM and other modes are limited to 120 watts.
Band plans and frequency allocations
The International Telecommunication UnionInternational Telecommunication Union
The International Telecommunication Union is the specialized agency of the United Nations which is responsible for information and communication technologies...
(ITU) governs the allocation of communications frequencies worldwide, with participation by each nation's communications regulation authority. National communications regulators have some liberty to restrict access to these bandplan
Bandplan
A bandplan or band plan is a plan for using a particular band of radio frequencies, that are a portion of the electromagnetic spectrum . Each bandplan defines the frequency range to be included, how channels are to be defined, and what will be carried on those channels...
frequencies or to award additional allocations as long as radio services in other countries do not suffer interference. In some countries, specific emission types
Types of radio emissions
The International Telecommunication Union uses an internationally agreed system for classifying radio frequency signals. Each type of radio emission is classified according to its bandwidth, method of modulation, nature of the modulating signal, and type of information transmitted on the carrier...
are restricted to certain parts of the radio spectrum, and in most other countries, International Amateur Radio Union
International Amateur Radio Union
The International Amateur Radio Union is an international confederation of national amateur radio organisations that allows a forum for common matters of concern and collectively represents matters to the International Telecommunication Union...
(IARU) member societies adopt voluntary plans to ensure the most effective use of spectrum.
In a few cases, a national telecommunication agency may also allow hams to use frequencies outside of the internationally allocated amateur radio bands. In Trinidad and Tobago
Trinidad and Tobago
Trinidad and Tobago officially the Republic of Trinidad and Tobago is an archipelagic state in the southern Caribbean, lying just off the coast of northeastern Venezuela and south of Grenada in the Lesser Antilles...
, hams are allowed to use a repeater which is located on 148.800 MHz. This repeater is used and maintained by the National Emergency Management Agency (NEMA), but may be used by radio amateurs in times of emergency or during normal times to test their capability and conduct emergency drills. This repeater can also be used by non-ham NEMA staff and REACT members. In Australia and New Zealand ham operators are authorized to use one of the UHF TV channels. In the U.S., in cases of emergency, amateur radio operators providing essential communication needs in connection with the immediate safety of human life and immediate protection of property when normal communication systems are not available may use any frequency including those of other radio services such as police and fire communications and the Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
statewide emergency frequency of 5167.5 kHz.
Similarly, amateurs in the United States may apply to be registered with the Military Auxiliary Radio System (MARS). Once approved and trained, these amateurs also operate on US government military frequencies to provide contingency communications and morale message traffic support to the military services.
Modes of communication
Amateurs use a variety of voice, text, image and data communications modes over radio. Generally new modes can be tested in the amateur radio service, although national regulations may require disclosure of a new mode to permit radio licensing authorities to monitor the transmissions. EncryptionEncryption
In cryptography, encryption is the process of transforming information using an algorithm to make it unreadable to anyone except those possessing special knowledge, usually referred to as a key. The result of the process is encrypted information...
, for example, is not generally permitted in the Amateur Radio service except for the special purpose of satellite vehicle control uplinks. The following is a partial list of the modes of communication used, where the mode includes both modulation
Modulation
In electronics and telecommunications, modulation is the process of varying one or more properties of a high-frequency periodic waveform, called the carrier signal, with a modulating signal which typically contains information to be transmitted...
types and operating protocols.
Voice
- Amplitude ModulationAmplitude modulationAmplitude modulation is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. AM works by varying the strength of the transmitted signal in relation to the information being sent...
(AM) - Double Sideband Suppressed CarrierSidebandIn radio communications, a sideband is a band of frequencies higher than or lower than the carrier frequency, containing power as a result of the modulation process. The sidebands consist of all the Fourier components of the modulated signal except the carrier...
(DSB-SC) - Independent SidebandIndependent sidebandIndependent sideband is an AM single sideband mode which is used with some AM radio transmissions. Normally each sideband carries identical information, but ISB modulates two different input signals — one on the upper sideband, the other on the lower sideband...
(ISB) - Single Sideband (SSB)
- Amplitude Modulation Equivalent (AME)
- Frequency ModulationFrequency modulationIn telecommunications and signal processing, frequency modulation conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant...
(FM) - Phase ModulationPhase modulationPhase modulation is a form of modulation that represents information as variations in the instantaneous phase of a carrier wave.Unlike its more popular counterpart, frequency modulation , PM is not very widely used for radio transmissions...
(PM)
Image
- Amateur TelevisionAmateur televisionAmateur television is the transmission of Broadcast quality video and audio over the wide range of frequencies of allocated for Radio amateur use. ATV is used for non-commercial experimentation, pleasure and public service events...
, also known as Fast Scan television (ATV) - Slow Scan TelevisionSlow-scan televisionSlow-scan television is a picture transmission method used mainly by amateur radio operators, to transmit and receive static pictures via radio in monochrome or color.A technical term for SSTV is narrowband television...
(SSTV) - FacsimileFaxFax , sometimes called telecopying, is the telephonic transmission of scanned printed material , normally to a telephone number connected to a printer or other output device...
Text and data
Most amateur digital modes are transmitted by inserting audio into the microphone input of a radio and using an analog scheme, such as amplitude modulationAmplitude modulation
Amplitude modulation is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. AM works by varying the strength of the transmitted signal in relation to the information being sent...
(AM), frequency modulation
Frequency modulation
In telecommunications and signal processing, frequency modulation conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant...
(FM), or single-sideband modulation
Single-sideband modulation
Single-sideband modulation or Single-sideband suppressed-carrier is a refinement of amplitude modulation that more efficiently uses electrical power and bandwidth....
(SSB).
- Continuous WaveContinuous waveA continuous wave or continuous waveform is an electromagnetic wave of constant amplitude and frequency; and in mathematical analysis, of infinite duration. Continuous wave is also the name given to an early method of radio transmission, in which a carrier wave is switched on and off...
(CW) - ALEAutomatic link establishmentAutomatic Link Establishment, commonly known as ALE, is the worldwide de facto standard for digitally initiating and sustaining HF radio communications. ALE is a feature in an HF communications radio transceiver system, that enables the radio station to make contact, or initiate a circuit, between...
Automatic Link Establishment - AMateur Teleprinting Over RadioAMTORAMTOR is a type of telecommunications system that consists of two or more electromechanical teleprinters in different locations that send and receive messages to one another. AMTOR is a specialized form of RTTY protocol...
(AMTOR) - D-StarD-STARD-STAR is a digital voice and data protocol specification developed as the result of research by the Japan Amateur Radio League to investigate digital technologies for amateur radio...
- EcholinkEcholinkEchoLink is a free computer-based Amateur Radio system that allows radio amateurs to communicate with other amateur radio operators using Voice over IP technology on the Internet for at least part of the path between them...
- HellschreiberHellschreiberThe Hellschreiber or Feldhellschreiber is a facsimile-based teleprinter invented by Rudolf Hell. Compared to contemporary teleprinters that were based on typewriter systems, the Hellschreiber was much simpler and more robust, with only two moving parts...
, also referred to as either Feld-Hell, or Hell - Discrete multi-tone modulation modes such as Multi Tone 63MT63MT63 is a digital radio modulation mode for transmission in high-noise situations developed by Pawel Jalocha SP9VRC. MT63 is designed for keyboard-to-keyboard conversation modes, on HF HAM bands.- Features and Attributes :...
(MT63) - Multiple Frequency-Shift KeyingMultiple frequency-shift keyingMultiple frequency-shift keying is a variation of frequency-shift keying that uses more than two frequencies. MFSK is a form of M-ary orthogonal modulation, where each symbol consists of one element from an alphabet of orthogonal waveforms...
(MFSK) modes such as- FSK441, JT6M, JT65WSJT (Amateur radio software)WSJT is a computer program used for weak-signal radio communication between amateur radio operators. The program was initially written by Joe Taylor, K1JT, but is now open source and is developed by a small team...
, and - Olivia MFSKOlivia MFSKOlivia MFSK is an amateur radioteletype protocol designed to work in difficult conditions on shortwave bands. The signal can still be properly copied when it is buried 10 dB below the noise floor...
- FSK441, JT6M, JT65
- Packet RadioPacket radioPacket radio is a form of packet switching technology used to transmit digital data via radio or wireless communications links. It uses the same concepts of data transmission via Datagram that are fundamental to communications via the Internet, as opposed to the older techniques used by dedicated...
(AX25) - Automatic Packet Reporting System (APRS)
- PACTORPACTORPACTOR is a radio modulation mode used by amateur radio operators, marine radio stations, and radio stations in isolated areas to send and receive digital information via radio. A robust network of PACTOR stations has been established to relay data between radio stations and the Internet,...
- Phase Shift Keying
- 31 baudBaudIn telecommunications and electronics, baud is synonymous to symbols per second or pulses per second. It is the unit of symbol rate, also known as baud rate or modulation rate; the number of distinct symbol changes made to the transmission medium per second in a digitally modulated signal or a...
binary phase shift keying: PSK31PSK31PSK31 or "Phase Shift Keying, 31 Baud" is a digital radio modulation mode, used primarily in the amateur radio field to conduct real-time keyboard-to-keyboard informal text chat between amateur radio operators.- History :... - 31 baudBaudIn telecommunications and electronics, baud is synonymous to symbols per second or pulses per second. It is the unit of symbol rate, also known as baud rate or modulation rate; the number of distinct symbol changes made to the transmission medium per second in a digitally modulated signal or a...
quadrature phase shift keying: QPSK31 - 63 baudBaudIn telecommunications and electronics, baud is synonymous to symbols per second or pulses per second. It is the unit of symbol rate, also known as baud rate or modulation rate; the number of distinct symbol changes made to the transmission medium per second in a digitally modulated signal or a...
binary phase shift keying: PSK63PSK63PSK63 or Phase Shift Keying, 63 Baud, is a digital radio modulation mode used primarily in the amateur radio field to conduct real-time keyboard-to-keyboard informal text chat between amateur radio operators.- History :... - 63 baudBaudIn telecommunications and electronics, baud is synonymous to symbols per second or pulses per second. It is the unit of symbol rate, also known as baud rate or modulation rate; the number of distinct symbol changes made to the transmission medium per second in a digitally modulated signal or a...
quadrature phase shift keying: QPSK63
- 31 baud
- Spread spectrumSpread spectrumSpread-spectrum techniques are methods by which a signal generated in a particular bandwidth is deliberately spread in the frequency domain, resulting in a signal with a wider bandwidth...
- Simplex Teletype Over RadioSITORSITOR is a system for transmitting text messages. Although it uses the same frequency-shift keying modulation used by regular radioteletype , SITOR uses error detection, redundancy, and/or retransmission to improve reliability.There are two SITOR modes:* SITOR-A is used for point to point links...
(SITOR) - Radio Teletype (RTTY)
- 8FSKAutomatic link establishmentAutomatic Link Establishment, commonly known as ALE, is the worldwide de facto standard for digitally initiating and sustaining HF radio communications. ALE is a feature in an HF communications radio transceiver system, that enables the radio station to make contact, or initiate a circuit, between...
8ary Frequency Shift Keying
Modes by activity
The following 'modes' use no one specific modulation scheme but rather are classified by the activity of the communication.- Earth-Moon-EarthEME (communications)Earth-Moon-Earth, also known as moon bounce, is a radio communications technique which relies on the propagation of radio waves from an Earth-based transmitter directed via reflection from the surface of the Moon back to an Earth-based receiver....
(EME) - Internet Radio Linking Project (IRLP)
- Low Transmitter PowerQRP operationIn amateur radio, QRP operation means transmitting at reduced power levels while aiming to maximize one's effective range while doing so. The term QRP derives from the standard Q code used in radio communications, where "QRP" and "QRP?" are used to request, "Reduce power," and ask "Should I reduce...
(QRP) - SatelliteOSCAROSCAR is an acronym for Orbiting Satellite Carrying Amateur Radio. OSCAR series satellites use amateur radio frequencies to facilitate communication between amateur radio stations. These satellites can be used for free by licensed amateur radio operators for voice and data communications...
(OSCAR)
See also
- List of amateur radio magazines
- List of amateur radio organizations
- Maritime mobile amateur radioMaritime mobile amateur radioMost countries' amateur radio licences allow licensed operators to install and use radio transmission equipment while at sea. Such operation is known as maritime mobile amateur radio...