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Amateur radio, often called ham radio, is both a hobby and a service that uses various types of radio communications equipment to communicate with other radio amateurs for public service, recreation and self-training. A participant is called an amateur radio operator, or a ham.

Amateur radio operators have personal wireless communications with friends, family members, and even complete strangers, and often support their communities with emergency and disaster communications while increasing their personal knowledge of electronics and radio theory. An estimated six million people throughout the world are regularly involved with amateur radio.

The term "amateur" is not a reflection on the skills of the participants, which are often quite advanced; rather, "amateur" indicates that amateur radio communications are not allowed to be made for commercial or money-making purposes.

History

Though its origins can be traced to at least the late 1800s, amateur radio, as practiced today, began in the 1920s. 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.

Activities and practices

Radio amateurs use various modes of transmission to communicate. Voice transmissions are most common, with some such as frequency modulation (FM) offering high quality audio, and others such as single sideband (SSB) offering more reliable communications when signals are marginal and bandwidth is restricted.

Radiotelegraphy using Morse code remains popular, particularly on the shortwave bands and for experimental work such as Moonbounce, with its inherent signal-to-noise ratio advantages. Morse, using internationally agreed code groups, also facilitates communications between amateurs who speak different languages. It is also popular with homebrewers as CW-only transmitters are simpler to construct. For many years, demonstrating a proficiency in Morse code was a requirement to obtain amateur licenses for the high frequency bands, but following changes in international regulations in 2003, many countries have now dropped this requirement (the United States Federal Communications Commission did so in 2007).

Modern personal computers have led to a boom in digital modes such as radioteletype, which previously required cumbersome mechanical equipment. Hams led the development of packet radio, which has even used protocols such as TCP/IP since the 1970s. This has since been augmented by more specialized modes such as PSK31 to facilitate 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 easy linking together of repeaters. Other modes, such as FSK441 using software such as WSJT, are used for weak signal modes including meteor scatter and moonbounce communications.

Similarly, fast scan amateur television, once considered rather esoteric, has exploded in popularity thanks to cheap camcorders and video cards in home computers. Because of the wide bandwidth and stable signals required, amateur television is typically found in the 70 cm (420—450 MHz) frequency range, though limited usage also exists on 33 cm (902—928 MHz), 23 cm (1240—1300 MHz) and higher. These requirements also effectively limit the signal range to between 20 and 60 miles (30—100 km), however, the use of linked repeater systems can allow transmissions across several states.

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 satellites called OSCARs (Orbiting Satellite Carrying Amateur Radio) can be accessed, some using a handheld transceiver (HT) with a stock "rubber duck" antenna. Hams also use natural satellites such as the moon 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 astronauts 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.

Licensing

In all countries, amateur radio operators are required to pass a licensing exam displaying knowledge and understanding of key concepts. In return, hams are granted operating privileges in larger segments of the radio frequency spectrum using a wide variety of communication techniques with higher power levels permitted. This practice is in contrast to other unlicensed personal radio services such as CB radio, Multi-Use Radio Service, or Family Radio Service / 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 callsigns. Some countries such as Great Britain and Australia have begun requiring a practical training course in addition to the written exams in order to obtain a beginner's license. These beginner's licenses are referred to as Foundation Licenses.

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. Licensees previously needed to demonstrate proficiency in Morse Code to obtain or upgrade a license. These requirements were phased out by the Federal Communications Commission, first from the entry-level Technician license in 1991, and eventually from all license classes on February 23, 2007. This conforms with international law, which no longer mandates Morse code testing, as well as views by the FCC that Morse code should be treated like other communications techniques, and that written testing is sufficient to prove that an applicant is qualified to obtain an amateur radio license. Some portions of the ham bands remain reserved for Morse code use only and the mode remains popular.

Template:Sidebar start While many hams simply enjoy talking to friends, others pursue a wide variety of specialized interests.

• Emergency communications
• Hand building homebrew amateur radio gear
• Designing new antennas
• Communicating via amateur satellites
• Severe weather spotting
• DX communication to far away countries
• DX-peditions
• Using the Internet Radio Linking Project (IRLP) to connect radio repeaters via the Internet
• Tracking vehicles using the Automatic Position Reporting System (APRS), which integrates with the GPS
• Engaging in the sport of contesting, earning awards, and collecting QSL cards
• Amateur Radio Direction Finding
• High Speed Telegraphy
• Low-power operation (QRP).
• Vintage amateur radios, such as those using vacuum tube technology
• Hamfests, club meetings and swap meets
• Portable, fixed, mobile and handheld operation
• VHF, UHF and microwave operation on amateur radio high bands

Template:Sidebar end

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. 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, the New Zealand Association of Radio Transmitters and South African Radio League. ( See Category:Amateur radio organizations)

Callsigns

Upon licensing, a radio amateur's national government issues a unique callsign to the radio amateur. The holder of a callsign uses it on the air to legally identify the operator or station during any and all radio communication. In certain jurisdictions, an operator may also select a "vanity" callsign. Some jurisdictions, such as the U.S., require that a fee be paid to obtain such a vanity callsign; in others, such as the UK, a fee is not required and the vanity callsign may be selected when the license is applied for.

Privileges

In contrast to most commercial and personal radio services, radio amateurs are not restricted to using type-approved equipment, and radio amateurs may home-construct or modify equipment in any way so long as they meet spurious emission standards.

As noted, radio amateurs have access to frequency allocations throughout the RF spectrum, enabling choice of frequency to enable effective communication whether across a city, a region, a country, a continent or the whole world regardless of season or time day or night. The shortwave bands, or HF, can facilitate worldwide communication, the VHF and UHF bands offer excellent regional communication, and the broad microwave bands have enough space, or bandwidth, for television (known as SSTV and FSTV) transmissions and high-speed data networks.

A distinguishing privilege of an amateur radio license is the ability to make relatively free use of variable frequency oscillators to control transmitter frequencies. The only other service allowed this privilege is the military. All other radio services must use 'type approved' transmitters that transmit on fixed frequencies.

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 power limits for the highest available license classes in a few selected countries are: 2.25 kilowatts in Canada, 2 kilowatts in most countries of the former Yugoslavia, 1.5 kilowatts in the United States, 1 kilowatt in Belgium and Switzerland, 750 watts in Germany, 500 watts in Italy, 400 watts in Australia and the United Kingdom, 150 watts in Oman and 100 watts in India. Lower license classes usually have lower power limits; for example, the lowest license class in the UK has a limit of just 10 watts.

When traveling abroad, the visiting ham must follow the rules of the country in which she or he wishes to operate. Some countries have reciprocal operating agreements to facilitate international operation, 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.

Band plans and frequency allocations

The International Telecommunication Union (ITU) governs the allocation of communications frequencies world-wide, with participation by each nation's communications regulation authority. National communications regulators have some liberty to restrict access to these 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 148.80 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 may use any frequency including those of other radio services such as police and fire communications and the Alaska statewide emergency frequency of 5165.7 kHz.

Similarly, amateurs in the United States may apply to be registered with the Military Affiliate 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.

Popular culture

Amateur radio can be found throughout popular culture as a plot device. A classic example would be the "Radio Ham" episode of 1960s British comedy series Hancock's Half Hour.

There are also famous Amateur radio operators, such as King Juan Carlos I of Spain, the late Prime Minister of India Rajiv Gandhi, radio and TV host Walter Cronkite, and Coast To Coast AM host Art Bell. Others include Gen. Curtis LeMay, Joe Walsh, Lance Bass, Barry Goldwater, Chet Atkins, Marlon Brando, King Hussein of Jordan, Patty Loveless, Ronnie Milsap, Bill "Bubba" Bussey from the nationally syndicated Rick and Bubba Show, Maine Governor John Baldacci, and Jean Shepherd, as well as most of the launched astronauts and cosmonauts.

References

Cited References

1. Lau, Mary E (2006-05-23). "Ham Radio Frequently Asked Questions". ARRL.org. Retrieved 2007-08-25. {{cite web}}: Check date values in: |date= (help)
2. Silver, H Ward (2004-04-23). Amateur Radio for Dummies. Indianapolis: Wiley Publishing. ISBN 0764559877. OCLC 55092631. {{cite book}}: Check date values in: |date= (help)
3. International Code of Signals (PDF). Bethesda, MD: National Imagery and Mapping Agency. 2003 . Pub. 102. Retrieved 2007-01-10.
4. Galbraith, E Art (2003-08-23). "KH6BB and "Mighty Mo," the Battleship Missouri". ARRL.org. Retrieved 2007-01-10. {{cite news}}: Check date values in: |date= (help)
5. Taggart, Ralph E (1993). "An Introduction to Amateur Television" (PDF). QST via ARRL.org: pp. 19—23. Retrieved 2007-06-02. {{cite journal}}: |pages= has extra text (help); Italic or bold markup not allowed in: |journal= (help); Unknown parameter |month= ignored (help)
6. Taylor, Joe (2001). "WSJT: New Software for VHF Meteor-Scatter Communication" (PDF). QST via ARRL.org. pp. 36–41. Retrieved 2007-01-11. {{cite news}}: Italic or bold markup not allowed in: |work= (help); Unknown parameter |month= ignored (help)
7. "ARISS: Amateur Radio on the International Space Station". ARRL.org. Retrieved 2007-01-10.
8. Jurrens, Gerald. "Astronaut (and Former Astronaut) Hams". gjurrens at Tellurian.com. Retrieved 2007-01-10. {{cite web}}: Italic or bold markup not allowed in: |work= (help)
9. Haag, Jerry. "Principles of Amateur Radio Net Control". SCC-AREA-RACES.org. Retrieved 2007-01-10.
10. "FCC to Drop Morse Testing for All Amateur License Classes". ARRL.org. 2006-12-19. Retrieved 2007-05-16. {{cite web}}: Check date values in: |date= (help)
11. "FCC Report and Order 06-178A1" (PDF). Federal Communications Commission. 2006-12-19. pp. p. 7. Retrieved 2007-05-16. {{cite web}}: |pages= has extra text (help); Check date values in: |date= (help)
12. "Amateur Radio (Intermediate) Licence (A) or (B) Terms, Provisions and Limitations Booklet BR68/I". Ofcom.org.uk. Retrieved 2007-06-02.
13. "Common Filing Task: Obtaining Vanity Call Sign". FCC.gov. Retrieved 2007-06-02.

General References

• Straw, R Dean (ed.) (2005). The ARRL Handbook for Radio Communications 2006 (83rd edition ed.). Newington, CT: American Radio Relay League. ISBN 0-87259-949-3. OCLC 62026192. {{cite book}}: |author= has generic name (help); |edition= has extra text (help); Unknown parameter |month= ignored (help)
• Bergquist, Carl J (2001-05-01). Ham Radio Operator's Guide (2nd edition ed.). Indianapolis: Prompt Publications. ISBN 0-7906-1238-0. OCLC 47051066. {{cite book}}: |edition= has extra text (help); Check date values in: |date= (help)
• Dennison, Mike and Chris Lorek (eds.) (2005). Radio Communication Handbook (8th edition ed.). Potters Bar, Hertfordshire, England: Radio Society of Great Britain. ISBN 1-90508608-3. OCLC 123027893. {{cite book}}: |author= has generic name (help); |edition= has extra text (help); Unknown parameter |month= ignored (help)
• Poole, Ian D (2001-10-31). HF Amateur Radio. Potters Bar, Hertfordshire, England: Radio Society of Great Britain. ISBN 1-872309-75-5. OCLC 47823876. {{cite book}}: Check date values in: |date= (help)

See also

• List of amateur radio organizations
• List of amateur radio operating modes

George Sweigert, inventor of the cordless phone, is one example of a famous "ham operator".

External links

• Template:Dmoz

• Amateur radio
• Radio hobbies