Amateur radio

Amateur radio, also known as Ham radio, is the use of specific bands and frequencies within the radio spectrum for non-commercial communication, technical experimentation, self-training, recreation, radiosport, contesting, and emergency communications.^[1] A surge of popular interest in radio experimentation in the early 20th century necessitated that parts of the radio spectrum be allocated to non-professionals. In 1927 a radio amateur was defined as "a duly authorized person interested in radioelectric practice with a purely personal aim and without pecuniary interest", meaning without monetary or similar reward. The definition distinguished amateur activity from commercial broadcasting, public safety services, and professional two-way radio uses such as maritime, aviation, and taxi communication.^[2]

The amateur radio service (amateur service and amateur-satellite service) is established by the International Telecommunication Union (ITU) through its Radio Regulations. National governments set technical and operational rules for transmissions and issue individual station licences with unique call signs. Call signs must be used in transmissions, at least every ten minutes and at the end of the conversation. Amateur radio operators must hold an amateur radio licence, granted after an examination that tests knowledge of radio theory, electronics, and national regulations.

Operators are authorised to transmit on frequency ranges allocated internationally as the amateur radio bands. Within these bands they may use any frequency, though some are restricted to particular modes of voice, text, image, or data communications. This allows communication locally, nationally, worldwide, and even with stations in space. In many countries, operators may also exchange radio communications between computers or transceivers connected through virtual private networks on the Internet.

Amateur radio is represented by the International Amateur Radio Union (IARU), which has three regions and includes national amateur radio societies in most countries. In 2011 the American Radio Relay League (the U.S. national society) estimated that about 2 million people worldwide were active in amateur radio.^[3] About 830,000 amateur radio stations are in Region 2 (the Americas), about 750,000 in Region 3 (South and East Asia and the Pacific), and about 400,000 in Region 1 (Europe, the Middle East, the CIS and Africa). Radio amateurs have been credited with a number of advancements, notably the discovery of skywave propagation.

History

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 a list of amateur radio stations.^[4] 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, like experimentation with quartz piezoelectric resonators from 1924 until about 1934,^[5] built economies,^[6] empowered nations,^[7] and saved lives in times of emergency.^[8]^[9] Ham radio can also be used in the classroom to teach English, map skills, geography, math, science, and computer skills.^[10]

Ham radio

The term ham was originally a pejorative, used in professional wired telegraphy during the 19th century to mock operators with poor Morse code-sending skills ("ham-fisted").^[11]^[12]^[13]^[14] This term continued to be used after the invention of radio and the subsequent proliferation of amateur experimentation with wireless telegraphy; among both land-based and sea-based professional radio telegraphers, ham amateurs were considered a nuisance. The use of ham to mean amateurish or unskilled survives to this day in another discipline— i.e. ham actor.

The amateur radio community subsequently reclaimed the word as a label of pride,^[15] and by the mid-20th century it had lost its pejorative meaning. Although not an acronym or initialism, it is occasionally written as "HAM" in capital letters.

Activity and practice

Amateur radio combines communication, technical experimentation, and recreation. Operators take part in contests, provide emergency service, build and modify equipment, and use transmission modes ranging from traditional Morse code to modern digital protocols.

Community and social use

Operators often join conversational groups and take part in scheduled on-air meetings called nets, coordinated by a net control station.^[16] Nets may provide training for emergencies, operate as informal discussions, or focus on specialised topics.^[17]

With battery- or generator-powered equipment, operators frequently provide communication during natural disasters when commercial services are unavailable.^[18]

Competitive activities include contests to contact as many stations as possible in a set period, and operating awards such as Summits on the Air, Worked All States, and Jamboree on the Air. Operators also contribute to citizen science by collecting propagation data and supporting atmospheric science research.^[19]

Voice (Radiotelephony) and Morse code (Radiotelegraphy)

Radiotelephony

The principal voice modes are frequency modulation (FM), single sideband (SSB), and amplitude modulation (AM). FM offers high audio quality, SSB is efficient for long-distance use,^[20] and AM continues among users of vintage amateur radio equipment.

Radiotelegraphy

Radiotelegraphy using International Morse code, or continuous wave (CW), is one of the oldest modes in amateur radio. Although largely replaced in professional services, it remains in use on shortwave bands because it functions under weak-signal conditions and employs internationally understood codes such as the Q code. CW is also used by hobbyists who build their own equipment (home construction) and by operators engaged in low-power operation, as CW transmitters are simple to construct and weak signals can often be received by ear.

Until 2003, Morse code proficiency was required under international regulations for access to frequencies below 30 MHz.^[21] The requirement was withdrawn in the United States in 2007.^[22]^[23]^[A]

Digital and computer-assisted modes

Personal computers have enabled new digital transmission modes. Radioteletype (RTTY), once operated by mechanical devices,^[24] is now handled in software. Packet radio, developed in the 1970s, uses protocols such as AX.25 and TCP/IP. Later modes including PSK31 and FT8 allow efficient low-signal communication on shortwave bands.

Radio over IP (RoIP) applies Internet-based telephony techniques to radio. EchoLink and the Internet Radio Linking Project link repeaters and operators worldwide.^[25]

Other specialised modes support weak-signal communication. Automatic link establishment (ALE) maintains networks on high-frequency bands, while the WSJT suite supports meteor scatter and moonbounce.^[26]

Television and repeater systems

Fast-scan amateur television (ATV) adapts consumer video equipment to transmit images. It typically operates on the 70 cm (420–450 MHz) but may also use the 33 cm and higher frequencies. Because of wide bandwidth requirements, ATV usually covers 30–100 km (20–60 mi). Linked repeater systems extend this range to several hundred kilometres.^[27] Repeaters are often located on high ground or towers and may be linked by other amateur bands, landlines, or the Internet.

Space and atmospheric propagation

Operators can use amateur radio satellites, sometimes with only a hand-held transceiver.^[28] Natural reflectors such as the Moon, the aurora borealis, and meteor trails are also used.^[29] Licensed astronauts have also made contacts from the International Space Station through the ARISS programme.^[30]^[31]

Licensing

Because radio signals can propagate across national borders, amateur radio is regulated by governments under international frameworks.^[32] National requirements generally follow standards set by the International Telecommunication Union (ITU)^[33] and World Radiocommunication Conferences.

Most countries require candidates to pass an examination that tests electronics, radio propagation, operating practices, and regulations.^[34] Licensing grants access to a broader portion of the spectrum, additional communication modes, and higher transmitter power than unlicensed personal radio services such as CB, FRS, or PMR446.^[35]

Examination systems often include several levels, each granting wider frequency access and higher power limits.^[36]^[37] In the United Kingdom and Australia, entry-level candidates must also complete a practical skills test to obtain the Foundation Licence, the first of three licensing stages.^[38]

Each licensee is normally assigned a unique call sign.^[39] Some countries issue additional station licences, or recognise club and organisational licences.^[40]

Licences are generally valid only in the issuing country or in states with reciprocal agreements.^[41]^[42] In some jurisdictions, a licence is also required to purchase or possess amateur radio equipment.^[43]

In the United States, the Federal Communications Commission (FCC) issues three licence classes: Technician, General, and Amateur Extra.^[44] Examinations are administered by accredited Volunteer Examiners through the FCC's Volunteer Examiner Coordinator system. Higher licence classes provide access to more frequency bands and higher transmitter power. The tests cover regulations, operating practices, electronics theory, equipment design, and safety. Morse code is no longer tested. Licences are valid for ten years, and the national question pools are published in advance and updated every four years.^[44]

Licensing requirements

Prospective amateur radio operators are examined on understanding of the key concepts of electronics, radio equipment, antennas, radio propagation, RF safety, and the radio regulations of the government granting the license.^[1] 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.^[1]

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). Currently, only Yemen and North Korea do not issue amateur radio licenses to their citizens.^[45]^[46] 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, Thailand, Canada, and most of the countries in Europe, there are frequent license examinations opportunities in major cities.

Granting 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.^[47] 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 a club or organization for a period of time before a higher class of license can be acquired.^[1]

Reciprocal licensing

A reciprocal licensing agreement between two countries allows licensed amateur radio operators from one country to operate stations in the other without obtaining a new licence. In some cases, visiting operators may be issued a temporary local licence and call sign.

Requirements vary by jurisdiction. Some countries have bilateral or multilateral agreements that harmonise conditions, while others have no reciprocal arrangements. Regional organisations, such as the Organization of American States, facilitate reciprocity through treaties, including the Inter-American Amateur Radio Service Convention.^[48]

Newcomers

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 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),^[49] within the ham community.^[50]^[51] 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 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)

Call signs

An amateur radio operator uses a call sign on the air to legally identify the operator or station.^[52] 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.^[53] 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.^[54] Some jurisdictions require a fee to obtain 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 reinstated it at $35 in 2022.^[55]

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	The first part may be one or two letters (or a single digit followed by a single letter); it shows the country from which the call sign originates and may also indicate the license class. (This call sign is licensed in South Africa.)
1	The second part is always a single digit that appears as the second or third character, and always follows a letter; it normally gives the subdivision of the country or territory indicated in the first part (this one refers to the Western Cape).
NAT	The third part is a set of one, two, or three letters that immediately follows the digit in the second part (the digit in the second or third character); it uniquely identifies the holder of the license. (In the examples below, the third part is represented by " $xxx$ ".)

The combination of the three parts identifies the specific transmitting station, and the station's identification (its call sign) is determined by the license held by its operator. In the case of commercial stations and amateur club stations, the operator is a corporation; in the case of amateur radio operators, the license-holder is a resident of the country identified by the first part of the call sign.

Many countries do not follow the ITU convention for the second-part digit. In the United Kingdom the original calls G0 $xxx$ , G2 $xxx$ , G3 $xxx$ , G4 $xxx$ , were Full (A) License holders along with the last M0 $xxx$ full call signs issued by the City & Guilds examination authority in December 2003. Additional Full Licenses were originally granted to (B) Licenses with G1 $xxx$ , G6 $xxx$ , G7 $xxx$ , G8 $xxx$ and 1991 onward with M1 $xxx$ call signs. The newer three-level Intermediate License holders are assigned 2E0 $xxx$ and 2E1 $xxx$ , and the basic Foundation License holders are granted call signs M3 $xxx$ , M6 $xxx$ or M7 $xxx$ .^[56]

Instead of using numbers, in the U.K. 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 the license holder is operating their station in Scotland. Prefix GM & MM are Scotland, GW & MW are Wales, GI & MI are Northern Ireland, GD & MD are the Isle of Man, GJ & MJ are Jersey and GU & MU are Guernsey. Intermediate licence call signs are slightly different. They begin 2 $z$ 0 and 2 $z$ 1 where the $z$ is replaced with one of 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, whose letter would be 'E'; however, letter 'E' is used, but only in intermediate-level call signs, and perplexingly never by the advanced licenses. For example 2E0 & 2E1 are used whereas the call signs beginning 'G' or 'M' for foundation and full licenses never use the 'E'.^[57]

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 a number after to indicate the political region; whereas the prefix CY indicates geographic islands. Prefixes VA1 and VE1 are used for Nova Scotia; VA2 & VE2 for Quebec; VA3 & VE3 for Ontario; VA4 & VE4 for Manitoba; VA5 & VE5 for Saskatchewan; VA6 & VE6 for Alberta; VA7 & VE7 for British Columbia; VE8 for the Northwest Territories; VE9 for New Brunswick; VY0 for Nunavut; VY1 for the Yukon; VY2 for Prince Edward Island; VO1 for Newfoundland; and VO2 for Labrador. CY is for amateurs operating from Sable Island (CY0) or St. Paul Island (CY9). Special permission is required to visit 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 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 digit at the second or third character might be part of the country identification. For example, VP2 $xxx$ is in the British West Indies, which is subdivided into VP2E $xx$ Anguilla, VP2M $xx$ Montserrat, and VP2V $xx$ British Virgin Islands. VP5 $xxx$ is in the Turks and Caicos Islands, VP6 $xxx$ is on Pitcairn Island, VP8 $xxx$ is in the Falklands, and VP9 $xxx$ is in Bermuda.

Online callbooks or call sign databases can be browsed or searched to find out who holds a specific call sign.^[58] An example of an online callbook is QRZ.com. Various partial lists of famous people who hold or held amateur radio call signs have been compiled and published.^[59]

Many jurisdictions (but not in the U.K. nor Europe) may issue specialty vehicle registration plates to licensed amateur radio operators.^[60]^[61] The fees for application and renewal are usually less than the standard rate for specialty plates.^[60]^[62]

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.^[63]^[a]^[64]^[b] 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^[65] 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 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 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 the spectrum to use as little power as possible to accomplish the communication.^[66] This is to minimise interference or electromagnetic compatibility (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 25 W.^[67]

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;^[68] 1.5 kW in the United States; 1.0 kW in Belgium, Luxembourg, Switzerland, South Africa, the United Kingdom, and New Zealand; 750 W in Germany; 500 W in Italy; 400 W in Australia and India; and 150 W in Oman.

Output power limits may also depend on the mode of transmission. In Australia, for example, 400 W may be used for SSB transmissions, but FM and other modes are limited to 120 W.

The point at which power output is measured may also affect transmissions: The United Kingdom measures at the point the antenna is connected to the signal feed cable, which means the radio system may transmit more than 400 W to overcome signal loss in the cable; conversely, the U.S. and Germany measure power at the output of the final amplification stage, which results in a loss in radiated power with longer cable feeds.^[69]

Certain countries permit amateur radio licence holders to hold a Notice of Variation that allows higher power to be used than normally allowed for certain specific purposes. E.g. in the UK some amateur radio licence holders are allowed to transmit using (33 dBw) 2.0 kW for experiments entailing using the moon as a passive radio reflector (known as Earth–Moon–Earth communication) (EME).

Band plans and frequency allocations

The International Telecommunication Union (ITU) governs the allocation of communications frequencies worldwide, with participation of each nation's communications regulation authority. National communications regulators have some liberty to restrict access to these band plan 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., 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 and in cases of disaster in Alaska may use the statewide emergency frequency of 5.1675 MHz with restrictions upon emissions.^[70]

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.

International amateur radio frequency allocations^[t1]

Range	Band	ITU Region 1	ITU Region 2	ITU Region 3
LF	2200 m	135.7–137.8 kHz
MF	630 m	472–479 kHz
MF	160 m	1.810–1.850 MHz	1.800–2.000 MHz
HF	80 / 75 m	3.500–3.800 MHz	3.500–4.000 MHz	3.500–3.900 MHz
	60 m	5.3515–5.3665 MHz
	40 m	7.000–7.200 MHz	7.000–7.300 MHz	7.000–7.200 MHz
	30 m^[t2]	10.100–10.150 MHz
	20 m	14.000–14.350 MHz
	17 m^[t2]	18.068–18.168 MHz
	15 m	21.000–21.450 MHz
	12 m^[t2]	24.890–24.990 MHz
	10 m	28.000–29.700 MHz
VHF	8 m^[t3]	40.000–40.700 MHz	N/a
	6 m	50.000–52.000 MHz (50.000–54.000 MHz)^[t4]	50.000–54.000 MHz
	5 m^[t3]	58.000–60.100 MHz	N/a
	4 m^[t3]	70.000–70.500 MHz	N/a
	2 m	144.000–146.000 MHz	144.000–148.000 MHz
	1.25 m	N/a	220.000–225.000 MHz	N/a
UHF	70 cm	430.000–440.000 MHz	430.000–440.000 MHz (420.000–450.000 MHz)^[t4]
	33 cm	N/a	902.000–928.000 MHz	N/a
	23 cm	1.240–1.300 GHz
	13 cm	2.300–2.450 GHz
SHF	9 cm	3.400–3.475 GHz^[t4]	3.300–3.500 GHz
	5 cm	5.650–5.850 GHz	5.650–5.925 GHz	5.650–5.850 GHz
	3 cm	10.000–10.500 GHz
	1.2 cm	24.000–24.250 GHz
EHF	6 mm	47.000–47.200 GHz
	4 mm^[t4]	75.500 GHz^[t3] – 81.500 GHz	76.000–81.500 GHz
	2.5 mm	122.250–123.000 GHz
	2 mm	134.000–141.000 GHz
	1 mm	241.000–250.000 GHz
THF	Sub-mm	Some administrations have authorized spectrum for amateur use in this region; others have declined to regulate frequencies above 300 GHz.
[t1]	All allocations are subject to variation by country. For simplicity, only common allocations found internationally are listed. See a band's article for specifics.
[t2]	HF allocation created at the 1979 World Administrative Radio Conference. These are commonly called the "WARC bands".
[t3]	This is not mentioned in the ITU's Table of Frequency Allocations, but many individual administrations have commonly adopted this allocation under "Article 4.4".
[t4]	This includes a currently active footnote allocation mentioned in the ITU's Table of Frequency Allocations. These allocations may only apply to a group of countries.
See also: Radio spectrum, Electromagnetic spectrum

Modes of communication

Amateurs use a variety of voice, text, image, and data communication 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. Encryption, for example, is not generally permitted in the amateur radio service except for the special purpose of satellite vehicle control uplinks.^[71] The following is a partial list of the modes of communication used, where the mode includes both modulation types and operating protocols.

Voice

Amplitude modulation (AM)
Amplitude modulation equivalent (AME)
Double sideband, suppressed carrier (DSB-SC)
Frequency modulation (FM)
Independent sideband (ISB)
Single sideband (SSB)
Phase modulation (PM)

Image

Amateur television (ATV), also known as fast scan television^[72]
Radiofax
Slow-scan television (SSTV)^[73]

Text and data

In former times, most amateur digital modes were transmitted by inserting audio into the microphone input of a radio and using an analog scheme, such as amplitude modulation (AM), frequency modulation (FM), or single-sideband modulation (SSB). Beginning in 2017, increased use of several digital modes, particularly FT8, became popular within the amateur radio community.^[74]

Text-modes

Continuous wave (CW), usually used for Morse code
Automatic link establishment (ALE)
Amateur teleprinting over radio (AMTOR)^[75]
PACTOR^[76]^[77]
Radioteletype (RTTY)
Hellschreiber, a.k.a. Feld-Hell or Hell

Digital modes

CLOVER^[78]
D-STAR^[79]
Digital mobile radio(DMR)^[80]
Fusion (Yaesu proprietary mode)^[81]
G-TOR^[82]
Discrete multi-tone modulation modes such as Multi Tone 63 (MT63)^[83]
Multiple frequency-shift keying (MFSK)^[84] modes:
- JS8Call
- Olivia MFSK^[85]^[86]
- WSJT^[87] software modes:
  - FSK441, JT6M, JT65, JT9, FT8, FT4
- WSPR
NXDN (Open public safety standard, used in amateur radio)
Packet radio^[88] (AX.25)
- Automatic Packet Reporting System (APRS)^[89]
Phase-Shift Keying
- 31-baud BPSK (binary phase shift keying) PSK31^[90]
- 31-baud QPSK (quadrature phase shift keying) QPSK31
- 63-baud BPSK (binary phase shift keying) PSK63
- 63-baud QPSK (quadrature phase shift keying) QPSK63

Modes by activity

The following "modes" use no one specific modulation scheme but rather are classified by the activity of the communication.

AllStarLink (AllStar / ASL)^[91]
Earth-Moon-Earth (EME)
EchoLink^[92]
Internet Radio Linking Project (IRLP)^[93]
Low transmit power (QRP)^[94]
Satellite (OSCAR – orbiting satellite carrying amateur radio)^[95]

Footnotes

↑ Hong Kong OFTA description of "radio amateur" privileges:
Radio amateurs are free to choose any radio equipment designed for the amateur service. Radio amateurs may also design and build their own equipment provided that the requirements and limitations specified in the Amateur Station Licence and Schedules thereto are complied with.^[63]
↑ FCC expectations of "radio amateurs":
They design, construct, modify, and repair their [own] stations. The FCC equipment authorization program does not generally apply to amateur station transmitters.^[64]

References

Notes

↑ The Federal Communications Commission (FCC) officially ended the Morse code proficiency test for all amateur radio license classes on February 23, 2007. The transition occurred in several stages over the preceding decades: 1991: The FCC first introduced a "no-code" Technician Class license, though code proficiency was still required to access frequencies below 30 MHz. 2000: The requirement for higher-level licenses (General and Amateur Extra) was standardized and reduced to a single speed of 5 words per minute (WPM). 2003: The International Telecommunication Union (ITU) modified international regulations, leaving it to individual countries to decide if Morse code should remain a requirement. December 15, 2006: The FCC released the official Report and Order announcing the total elimination of the Morse code exam. February 23, 2007: The new rules became effective, allowing applicants to earn any class of license by passing only the written theory examinations.

Citations

1 2 3 4 Silver, H. Ward (2021). Ham Radio For Dummies (4th ed.). Hoboken, NJ: Wiley. ISBN 978-1-119-69576-9. OCLC 1245417767.
↑ "General Regulations Annexed to the International Radiotelegraph Convention" (PDF). International Radiotelegraph Convention of Washington, 1927. London, UK: His Majesty's Stationery Office. 1928. pp. 29–172. Archived from the original (PDF) on 28 July 2017. Retrieved 4 June 2017.
↑ Sumner, David (August 2011). "How Many Hams?". QST. American Radio Relay League. p. 9.
↑ Gernsback, H (May 1909). First Annual Official Wireless Blue Book of the Wireless Association of America (PDF). New York: Modern Electrics Publication. Archived (PDF) from the original on 6 July 2010. Retrieved 19 June 2009.
↑ Brown, Patrick R.J. (5–7 June 1996). "The influence of amateur radio on the development of the commercial market for quartz piezoelectric resonators in the United States". Proceedings of 1996 IEEE International Frequency Control Symposium. 1996 IEEE International Frequency Control Symposium. Honolulu, HI: Institute of Electrical and Electronics Engineers (IEEE) (published 1996). pp. 58–65. doi:10.1109/FREQ.1996.559819. ISBN 0-7803-3309-8. Archived from the original on 13 January 2013. Retrieved 22 December 2008.
↑ "Inventor of IC 'chip', Nobel Prize winner Jack S. Kilby credits amateur radio for his start in electronics". 20 June 2005. Archived from the original on 5 November 2012. Retrieved 22 November 2012 – via Nobelprize.org.
↑ Rahman, Bazlur (19 July 2004). Role of amateur radio in development communication of Bangladesh (PDF). Information & Communication Technology for Development (ICT4D) (Report). Bangladesh NGOs Network for Radio & Communication (BNNRC). Blacksburg, VA: Virginia Tech. Archived from the original (PDF) on 18 May 2015. Retrieved 11 May 2015 – via cimap.vt.edu.
↑ Taylor, Jim (29 December 2004). "Amateur radio "saved lives" in south Asia". Canadian Amateur Radio Bulletin. Radio Amateurs of Canada. Archived from the original on 6 March 2012. Retrieved 22 November 2012 – via Hfradio.net.
↑ "What is ham radio?". American Radio Relay League. Archived from the original on 4 May 2010. Retrieved 1 June 2010.
↑ Weaver, Bruce D. (January 2003). "On the Air Learning". Teaching Pre K-8. 33 (4): 50–51. ISSN 0891-4508.
↑ "Ham fisted". QST magazine. ARRL. August 1972. p. 83.
↑ Brady, Jasper Ewing (1899). Tales of the Telegraph. Doubleday & McClure. OCLC 3421513.
↑ "Ham radio history". American Radio Relay League. Archived from the original on 10 May 2015. Retrieved 17 April 2015.
↑ Hall, L.C. (January 1902). "Telegraph talk and talkers: The slang of the wire". McClure's Magazine. Vol. 18, no. 3. p. 231.
↑ Warner, Kenneth B., ed. (January 1920). "QST subscription contest". QST magazine. Vol. 3, no. 6. American Radio Relay League. pp. 32–33.
↑ Haag, Jerry. "Principles of Amateur Radio Net Control". SCC-AREA-RACES.org. Archived from the original on 7 May 2006. Retrieved 10 January 2007.
↑ Kinsner, Witold (2014). Enhanced crowdsourcing for disasters through ham-radio operators. 2014 IEEE Canada International Humanitarian Technology Conference (IHTC). Montreal: IEEE. pp. 1–6. doi:10.1109/IHTC.2014.7147544. ISBN 978-1-4799-3996-1. S2CID 20132820.
↑ Edwards, Lynn Ellen (1994). The Utilization of Amateur Radio in Disaster Communications. Working paper. Vol. 86. University of Colorado, Boulder. Natural Hazards Research and Applications Information Center / DIANE Publishing. ISBN 0-7881-1097-7.
↑ "Radio Blackout! Ham Radio as an Operational and Scientific Instrument". EOS. 16 February 2015. Retrieved 10 January 2025.
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↑ Deacon, Chris; Mitchell, Cathryn; Watson, Robert (2 June 2022). "Consolidated amateur radio signal reports as indicators of intense sporadic E layers". Atmosphere. 13 (6): 906. Bibcode:2022Atmos..13..906D. doi:10.3390/atmos13060906. ISSN 2073-4433.
↑ Taggart, Ralph E. (April 1993). "An introduction to amateur television" (PDF). QST. ARRL: 19–23. Archived from the original (PDF) on 5 June 2007. Retrieved 10 January 2025.
↑ Holmstead, Stephen (30 December 1994). "Amateur Satellite FAQ". The Radio Amateur Satellite Corporation. Archived from the original on 6 January 2010. Retrieved 14 March 2010.
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↑ "ARISS: Amateur radio on the International Space Station". ARRL.org. American Radio Relay League. Archived from the original on 11 January 2007. Retrieved 10 January 2007.
↑ Jurrens, Gerald. "Astronaut (and Former Astronaut) Hams". Tellurian.com. Archived from the original on 30 December 2006. Retrieved 10 January 2007.
↑ Hendy, David (2000). Radio in the Global Age. Cambridge; Malden, MA: Polity Press; Blackwell Publishers. ISBN 978-0-7456-2068-8.
↑ "Amateur and Amateur-satellite service". International Telecommunication Union. Archived from the original on 22 August 2010. Retrieved 16 August 2010.
↑ "Minimum Qualifications For Radio Amateurs". International Telecommunication Union. 1 May 2000. Archived from the original on 12 October 2012. Retrieved 22 November 2012.
↑ Kasser, J. E. (1995). Amateur radio: Past, present and future. International Conference on 100 Years of Radio. IEE. pp. 120–127. doi:10.1049/cp:19950801. ISBN 978-0-85296-649-5.
↑ Segal, Paul M. (1931). "The Regulation of Amateur Radio Communication". Air Law Review. 2: 153–170.
↑ Rappaport, Theodore S. (2022). "Crucible of Communications: How Amateur Radio Launched the Information Age and Brought High Tech to Life. Part 1: The Birth and Breadth of the Ham Radio Hobby". IEEE Communications Magazine. 60 (10): 6–10. Bibcode:2022IComM..60j...6R. doi:10.1109/MCOM.2022.9928087. ISSN 0163-6804.
↑ Wait, Phil (2015). "Not your grandfather's HAM radio". Journal of Telecommunications and the Digital Economy. 3 (4): 155–165. doi:10.18080/jtde.v3n4.41.
↑ Bogdan, Cristian; Bowers, John (2007). "Tuning In: Challenging Design for Communities through a Field Study of Radio Amateurs". In Steinfield, Charles; Pentland, Brian T.; Ackerman, Mark; Contractor, Noshir (eds.). Communities and Technologies 2007. London: Springer. pp. 439–461. Bibcode:2007cat..book..439B. doi:10.1007/978-1-84628-905-7_22. ISBN 978-1-84628-904-0.
↑ "见证共和国业余无线电发展的人：专访童晓勇/BA1AA" [Interview with Tong Xiaoyong (BA1AA), a witness to the development of amateur radio in the PRC]. CQ现代通信 (in Chinese). No. 2017–2. 北京博趣出版有限责任公司. p. 65. ISSN 1000-6559.
↑ de la Cruz Silveira Zavala, J. (1995). "A new CITEL fosters telecommunications in the Americas". IEEE Communications Magazine. 33 (9): 128–131. Bibcode:1995IComM..33i.128D. doi:10.1109/35.408437.
↑ Lin, Chun Hung (2002). "Regionalism or Globalism: The Process of Telecommunication Cooperation within the OAS and NAFTA". Currents: International Trade Law Journal. 11: 30–46.
↑ "Amateur radio licensing in Thailand: The equipment licence". Radio Amateur Society of Thailand. 7 August 2010. Archived from the original on 26 February 2011. Retrieved 13 February 2011.
1 2 "Amateur Licensing Examinations". Federal Communications Commission. Archived from the original on 29 May 2016. Retrieved 23 May 2016.
↑ Bovitz, J. S. (2017). Travels and Adventures in Ham Radio with Hon. John T. Laney III. American Bankruptcy Institute Journal, 36(4), 54.
↑ Ward, John (29 June 2021). "Bouncing signals off the moon: Amateur Radio Club draws young and experienced 'ham' operators". The Dispatch. Retrieved 21 July 2024.
↑ Rappaport, Theodore S. (2022). "Crucible of Communications: How Amateur Radio Launched the Information Age and Brought High Tech to Life: Part 1: The Birth and Breadth of the Ham Radio Hobby Invited Article". IEEE Communications Magazine. 60 (10): 6–10. Bibcode:2022IComM..60j...6R. doi:10.1109/MCOM.2022.9928087. ISSN 0163-6804.
↑ "Inter-American Amateur Radio Service Convention". OAS.org. Organization of American States. Retrieved 23 August 2022.
↑ Edwards, Mark W., ed. (c. 2013). "Technical find an 'Elmer'". 285 TechConnect Radio Club. Archived from the original on 15 March 2015. Retrieved 22 November 2012. which cites Rick Lindquist (N1RL) and
Newkirk, Rod (March 1971). "How's DX". QST magazine (regular column). ARRL.
↑ "ARRL mentor program". American Radio Relay League. Archived from the original on 14 October 2007.
↑ Wilson, Mark J; Reed, Dana G (2006). The ARRL Handbook for Radio Communications 2007 (84th ed.). Newington, CT: American Radio Relay League. ISBN 0-87259-976-0.
↑ Terms, Provisions, and Limitations (Report). Amateur Radio (Intermediate) License (A) or (B). London, UK: U.K. Radio & Media Licensing Authority. Booklet BR68/I. Archived from the original on 30 September 2007. Retrieved 18 April 2006.
↑ Terms, Provisions, and Limitations (pamphlet). Amateur Radio (Intermediate) License (A) or (B). London, UK: U.K. Radio & Media Licensing Authority. Booklet BR68/I. Archived from the original on 30 September 2007. Retrieved 2 June 2007.
↑ "Obtaining vanity call sign". U.S. Federal Communications Commission. Common Filing Task. Archived from the original on 27 August 2007. Retrieved 2 June 2007 – via FCC.gov.
↑ "Vanity call sign fees". arrl.org. American Radio Relay League. Archived from the original on 29 September 2015. Retrieved 28 September 2015.
↑ "U.K. amateur radio call signs (callsigns)". Electronics Notes. 2016. Archived from the original on 17 October 2016. Retrieved 17 October 2016 – via electronics-notes.com.
↑ More information is available from the Ofcom website:
"U.K. Radio & Media Licensing Authority". U.K. Radio & Media Licensing Authority. Archived from the original on 27 June 2004.
↑ "License search". FCC Universal Licensing System. U.S. Federal Communications Commission. Archived from the original on 22 August 2010. Retrieved 29 August 2010 – via wireless2.fcc.gov.
↑ "Famous radio amateurs 'hams' & [their] call signs". Bedworth Lions Club. Archived from the original on 31 August 2010. Retrieved 29 August 2010.
1 2 "Amateur radio license plate fees". ARRL.org. American Radio Relay League. Archived from the original on 4 August 2007.
↑ "Ham radio call sign license plates". Radio Amateurs of Canada. Archived from the original on 7 December 2008. Retrieved 4 December 2008.
↑ "HAM radio plates". Insurance Corporation of British Columbia. Archived from the original on 19 October 2008. Retrieved 3 December 2008.
1 2 "Annex F: Equipment for Amateur Station" (PDF). Office of the Telecommunications Authority. Archived from the original (PDF) on 27 September 2011. Retrieved 23 May 2010.
1 2 "Amateur Radio Service". Wireless Telecommunications. U.S. Federal Communications Commission. 6 July 2017. Archived from the original on 13 October 2019. Retrieved 20 November 2019.
↑ "Australian radio amateur FAQ". AMPR.org. 24 June 2006. Archived from the original on 18 July 2008.
↑ "§97.313—Transmitter power standards". Amateur Radio Service (regulations). Code of Federal Regulations. Government Printing Office. 2019. Title 47, Part 97, Section 97.313.
↑ Amateur Radio Wireless Telegraphy Licence Conditions (PDF). Ofcom (booklet). London, UK: U.K. Radio & Media Licensing Authority. 12 March 2025.
↑ "Standards for the Operation of Radio Stations in the Amateur Radio Service". Industry Canada. Government of Canada. September 2007. RBR-4 – s. 10.2. Archived from the original on 13 January 2013. Retrieved 21 January 2013.
↑ "47 CFR 97.3 -- Definitions". www.ecfr.gov. Retrieved 8 July 2026.
↑ "Providing Emergency Communications". Amateur Radio Service (regulation). Code of Federal Regulations. Government Printing Office. 2019. Title 47, Part 97, Subpart E.
↑ "§97.313—Prohibited transmissions". Amateur Radio Service (regulations). Code of Federal Regulations. Government Printing Office. 1998. Title 47, Chapter 1, Subchaper D, Part 97, Subpart B.
↑ "ATV - Fast-Scan Amateur Television". www.arrl.org. Retrieved 22 May 2025.
↑ "SSTV - Slow Scan Television". www.arrl.org. Retrieved 22 May 2025.
↑ "2017 was the year when digital modes changed forever". Mode usage evaluation. American Radio Relay League (analysis). Newington, CT. 22 January 2018. Retrieved 9 May 2022.
↑ "AmTOR: Amateur Telex Over Radio » Electronics Notes". www.electronics-notes.com. Retrieved 22 May 2025.
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↑ "Clover". www.arrl.org. Retrieved 22 May 2025.
↑ "Home - D-STAR Info". www.dstarinfo.com. Retrieved 22 May 2025.
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↑ "WHAT IS SYSTEM FUSION? | SystemFusion". Retrieved 22 May 2025.
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↑ "MT-63". www.arrl.org. Retrieved 22 May 2025.
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↑ "Orbiting Satellites Carrying Amateur Radio – AMSAT". Retrieved 22 May 2025.

Australia

Bertrand, Ron; Wait, Phil (2005). Your Entry Into Amateur Radio: The foundation license manual (1st ed.). Wireless Institute of Australia. ISBN 0-9758342-0-7.

Canada

Cleveland-Iliffe, John; Smith, Geoffrey Read (1995). The Canadian Amateur Study Guide for the Basic Qualification (5th ed.). Radio Amateurs of Canada. ISBN 1-895400-08-2.

India

Shaji, P.B. (2013). "Introduction to Amateur Radio". HamRadioIndia.

United Kingdom

Betts, Alan (2004). Foundation License Now! (3rd ed.). Radio Society of Great Britain. ISBN 1-872309-80-1.

United States

Wolfgang, Larry D., ed. (2003). Now You're Talking! All you need for your first amateur radio license (5th ed.). American Radio Relay League. ISBN 0-87259-881-0 – via Internet Archive (archive.org).
Hennessee, John, ed. (2003). The ARRL FCC Rule Book (13th ed.). American Radio Relay League. ISBN 0-87259-900-0.
Silver, H. Ward (2004). Ham Radio for Dummies. John Wiley & Sons. ISBN 0-7645-5987-7.

External links

Wikimedia Commons has media related to Amateur radio.

Amateur Radio (Ham) Glossary

Wikiversity has learning resources about Amateur radio

Wikibooks has a book on the topic of: Amateur Radio Manual

Amateur radio

General

Activities

Radiosport

ARDF	Fox Oring ROCA
DXing	MW DX Shortwave DX TV and FM DX
Contesting	Field Day SO2R WRTC Logging software technology Controversies HamSphere

Culture

Governance

Organizations	IARU ITU SRRC ARRL
Licensing	Call signs USA India Frequencies Licence categories Australia China UK Japan Europe Africa Korea Russia Mexico Canada

Modes

Voice	AM DSB-SC ISB SSB AME FM PM
Television	ATV SSTV
Data/digital	CW ALE AMTOR D-STAR DAPNET EchoLink FT8 Hellschreiber DMT FSK MFSK M17 Packet radio APRS AMPRNet KA9Q PACTOR PSK RTTY Spread spectrum WIRES-X DMR

Technologies

Emergency

Space & stratosphere

BEAR
Space Shuttle
ISS
Satellite
- OSCAR 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 16, 17, 18, 22, 38, 40, 44, 45, 50, 51, 53, 56, 60, 61, 62, 63, 65, 66, 67, 69, 71, 73, 75, 76, 77, 78, 83, 84, 85, 87, 91, 92, 95, 100, 101, 103, 104, 107, 109, 115, 116, 122
- ANUSAT
- ASUSat
- BugSat 1
- CAPE-1
- CAPE-2
- Delfi-C3
- Eyesat-1
- FalconSAT
- FITSAT-1
- HAMSAT
- INVADER
- ITF-1
- JAWSAT
- Kedr
- KITSAT-1
- KITSAT-2
- KITSAT-3
- KiwiSAT
- OSSI-1
- PANSAT
- PICS
- PCSat2
- PoSAT-1
- SEDSAT-1
- SRMSAT
- STARSHINE
- Starshine 3
- SuitSat
- SUNSAT
- TiungSAT-1
- UoSAT-2
- UoSAT-3
- UoSAT-4
- UoSAT-12

v t e Amateur radio digital modes
Frequency-shift keying (FSK)	RTTY AMTOR / SITOR PACTOR CLOVER2000 Packet radio (Bell 103 Bell 202) M17
Multiple frequency-shift keying (MFSK)	Olivia MFSK Contestia JT65 FSK441 JT6M WSPR FT8
Phase-shift keying (PSK)	PSK31 PSK63 Q15X25
COFDM	MT63 (based on PSK)
Non-traditional digital modes	Hellschreiber (Feld-Hell) On–off keying Continuous wave Modulated continuous wave Pulse modulation Frequency-hopping spread spectrum (FHSS) Direct-sequence spread spectrum (DSSS) AMPRNet DAPNET

v t e Antenna types
Isotropic	Isotropic radiator
Omnidirectional	Batwing antenna Biconical antenna Cage aerial Coaxial antenna Crossed field antenna Dielectric resonator antenna Dipole antenna Discone antenna Folded unipole antenna Franklin antenna Ground-plane antenna G5RV antenna Halo antenna Helical antenna Inverted-F antenna Inverted vee antenna J-pole antenna Mast radiator Monopole antenna Random wire antenna Rubber ducky antenna Sloper antenna Turnstile antenna T2FD antenna T-antenna Umbrella antenna Whip antenna
Directional	Adcock antenna AS-2259 Antenna AWX antenna Beverage antenna Cantenna Cassegrain antenna Choke ring antenna Collinear antenna array Conformal antenna Controlled reception pattern antenna Corner reflector antenna Curtain array Folded inverted conformal antenna Fractal antenna Gizmotchy Helical antenna Horn antenna Log-periodic antenna Loop antenna Microstrip antenna Moxon antenna Offset dish antenna Patch antenna Phased array Planar array Parabolic antenna Plasma antenna Quad antenna Reflective array antenna Regenerative loop antenna Rhombic antenna Sector antenna Short backfire antenna Slot antenna Sterba antenna Vivaldi antenna WokFi Yagi–Uda antenna
Application-specific	ALLISS Corner reflector (passive) Evolved antenna Ground dipole Reconfigurable antenna Rectenna Reference antenna Spiral antenna Circularly disposed antenna array Television antenna

v t e Two-way radio
Amateur and hobbyist	Amateur radio Amateur radio repeater Citizens band radio Family Radio Service Public Radio Service General Mobile Radio Service KDR 444 LPD433 Mobile rig Multi-Use Radio Service PMR446 UHF CB (Australia)
Aviation (aeronautical mobile)	Air traffic control Aircraft emergency frequency Airband Common traffic advisory frequency Mandatory frequency airport MULTICOM Single Frequency Approach UNICOM
Land-based commercial and government mobile	Base station Business band Mobile radio Professional mobile radio Radio repeater Specialized Mobile Radio Trunked radio system Walkie-talkie
Marine (shipboard)	2182 kHz 500 kHz Coast radio station Marine VHF radio Maritime mobile amateur radio
Signaling / Selective calling	CTCSS D-STAR Dual-tone multi-frequency MDC-1200 Push-to-talk Quik-Call I Quik-Call II Selcall SELCAL
System elements and principles	Antenna APRS Automatic vehicle location Call sign CAD DC remote Dispatch Dynamic range compression Fade margin Link budget Rayleigh fading Tone remote Radiotelephony procedure Voting (diversity combining)

v t e International Morse code
Transmission methods	Continuous wave Electrical telegraph Heliograph Modulated continuous wave On–off keying Paraset Signal lamp
Notable signals	SOS CQD Morse code mnemonics Prosigns for Morse code Morse code abbreviations Q code Z code
Other writing systems in Morse code	American Morse code Greek alphabet Cyrillic script Russian Hebrew script Arabic script Wabun code Chinese telegraph code

v t e Telecommunications
History	Beacon Broadcasting Cable protection system Cable TV Communications satellite Computer network Data compression audio DCT image video Digital media Internet video online video platform social media streaming Drums Edholm's law Electrical telegraph Fax Heliographs Hydraulic telegraph Information Age Information revolution Internet Mass media Mobile phone Smartphone Optical telecommunication Optical telegraphy Pager Photophone Prepaid mobile phone Radio Radiotelephone Satellite communications Semaphore Phryctoria Semiconductor device MOSFET transistor Smoke signals Telecommunications history Telautograph Telegraphy Teleprinter (teletype) Telephone history The Telephone Cases Television digital streaming Undersea telegraph line Videotelephony Whistled language Wireless revolution
Pioneers	Nasir Ahmed Edwin Howard Armstrong Mohamed M. Atalla John Logie Baird Paul Baran John Bardeen Alexander Graham Bell Emile Berliner Tim Berners-Lee Francis Blake Jagadish Chandra Bose Charles Bourseul Walter Houser Brattain Vint Cerf Claude Chappe Yogen Dalal Donald Davies Daniel Davis Jr. Amos Dolbear Thomas Edison Philo Farnsworth Reginald Fessenden Lee de Forest Elisha Gray Oliver Heaviside Robert Hooke Erna Schneider Hoover Harold Hopkins Gardiner Greene Hubbard Bob Kahn Dawon Kahng Charles K. Kao Narinder Singh Kapany Hedy Lamarr Roberto Landell Innocenzo Manzetti Guglielmo Marconi Robert Metcalfe Antonio Meucci Samuel Morse Jun-ichi Nishizawa Charles Grafton Page Radia Perlman Alexander Stepanovich Popov Tivadar Puskás Johann Philipp Reis Claude Shannon Almon Brown Strowger Henry Sutton Charles Sumner Tainter Nikola Tesla Camille Tissot Alfred Vail Thomas A. Watson Charles Wheatstone Vladimir K. Zworykin Internet pioneers
Transmission media	Coaxial cable Fiber-optic communication optical fiber Free-space optical communication Molecular communication Radio waves wireless Transmission line telecommunication circuit
Network topology and switching	Bandwidth Links Network switching circuit packet Nodes terminal Telephone exchange
Multiplexing	Space-division Frequency-division Time-division Polarization-division Orbital angular-momentum Code-division
Concepts	Communication protocol Computer network Data transmission Store and forward Telecommunications equipment
Types of network	Cellular network Ethernet ISDN LAN Mobile NGN Public Switched Telephone Radio Television Telex UUCP WAN Wireless network
Notable networks	ARPANET BITNET CYCLADES FidoNet Internet Internet2 JANET NPL network TANet Toasternet Usenet
Locations	Africa Americas North South Antarctica Asia Europe Oceania Global telecommunications regulation bodies
Telecommunication portal Category Outline Commons

Authority control databases
International	GND
National	United States Japan Israel
Other	Yale LUX