Amateur radio
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Image:Andaman dx-pedition.jpg Amateur radio, often called ham radio, is a hobby enjoyed by about 3 million people<ref name=dummies>Template:Cite book</ref> throughout the world. An amateur radio operator, ham, or radio amateur uses two-way radio to communicate with other radio amateurs for public service, recreation and self-improvement.
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History
Throughout its history, amateur radio enthusiasts have made significant contributions to science, engineering, industry, and social services. The economic and social benefit derived from research by amateur radio operators has founded new industries, built economies, empowered nations, and saved lives.
The birth of amateur radio and radio in general has mostly been associated with the original experimenter. Heinrich Rudolf Hertz (1888), and later experimenters. There are many contenders as the inventor of radio, that honor has been disputed between not only Hertz and Marconi, but also Amos Dolbear, Reginald Fessenden, James Clerk Maxwell, Sir Oliver Lodge, Mahlon Loomis, Nathan Stubblefield<ref name="inventr">Template:Cite web</ref> and Alexander Popov<ref name=invent2>Template:Cite web</ref>, and Nikola Tesla<ref name=invent>Template:Cite web</ref>. Guglielmo Marconi, from 1895 to 1899, sent wireless messages across the English Channel and, reportedly, the first transatlantic transmission (1902) <ref name="fcc hist">Template:Cite web</ref>. In the period following Marconi's experiments (1900-1908) many people throughout the world began experimenting with radio. Communications were made in Morse Code by use of spark gap transmitters or high frequency alternators. These first amateur radio operators are the roots of the modern international phenomenon of amateur radio.
In 1912, the United States Congress passed the Radio Act of 1912 <ref name="fcc hist">Template:Cite web</ref> which also restricted private stations to wavelengths of 200 meters or shorter (1500 kHz or higher).<ref name="Wireless Radio">Template:Cite book</ref> These frequencies at the time were generally considered useless and the number of radio hobbyists dropped by as much as an estimated 88%.<ref name="200 Meters">Template:Cite book</ref>) By this time, the term "ham" for an amateur radio operator was well established, the origins of which are obscure.<ref name="ham orig1">Template:Cite web</ref> <ref name="ham orig2">Template:Cite web</ref> <ref name="ham orig3">Template:Cite web</ref>
By 1917, World War I had put a stop to amateur radio. In the United States, the Congress had actually ordered all amateur radio operators to cease operation and even dismantle their equipment.<ref name="beginner">Template:Cite book</ref>
A challenge was issued by American hams to their counterparts in the United Kingdom in 1921 to receive radio contacts from across the Atlantic. Soon, many American stations were beginning to be heard in the UK, shortly followed by a UK amateur being heard in the US by December of 1922. The first two way contact between the UK and USA was in December, 1923. between London and West Hartford, CT.<ref name="trans">Template:Cite web</ref>
The International radiotelegraph conference was held in Washington, DC, USA in 1927-28.<ref name="fcc hist">Template:Cite web</ref> At the conference, the familiar amateur radio bands of 80, 40, 20 & 10 meters were established by treaty and international radio callsign prefixes were devised.
During the Nazi occupation of Poland, Fr. Maximilian Kolbe, SP3RN was arrested by the Nazis as a priest.<ref name=saint>Template:Cite web</ref> The Nazis believed his amateur radio activities were somehow involved in espionage<ref name=hamspy>Template:Cite web</ref> and he was transferred to Auschwitz on the 28th of May, 1941. After some prisoners escaped in 1941, The Nazis ordered that 10 prisoners be killed in retribution. Fr. Kolbe was martyred when he volunteered to take the place of one of the condemned men. On the 10th of October, 1982 he was canonized by Pope John Paul II as Saint Maximilian Kolbe, Apostle of Consecration to Mary and declared a Martyr of charity<ref name=saint>Template:Cite web</ref>. He is considered the Patron saint of Amateur radio operators.<ref name=hamspy />
Again during World War II, as it had done during the first World War, the United States Congress suspended all amateur radio operations<ref name="Wireless Radio">Template:Cite book</ref> . With most of the American amateur radio operators in the armed forces at this time, the US government created the War emergency radio service which would remain active through 1945. After the War the amateur radio service began operating again.
In 1961 the first orbital satellite carrying amateur radio (OSCAR) was launched. Oscar I would be the first of a series of amateur radio satellites created throughout the world. <ref name=amsat>Template:Cite web</ref>
The World administrative radio conference met in Geneva, Switzerland in 1979. Among the many topics covered at this meeting was the creation of three new amateur radio bands: 30 meters, 17 meters and 12 meters<ref name=warc>Template:Cite web</ref>. Today, these three bands are referred to collectively as the WARC bands by amateur radio operators.
During the Falklands War in 1982, Argentine forces seized control of the phones and radio network on the islands and had cut off communications with London. Scottish amateur radio operator Les Hamilton, GM3ITN<ref name="GM3ITN">Template:Cite web</ref><ref name="VP8ITN">Template:Cite web</ref> was able to relay crucial information from fellow hams Bob McLeod and Tony Pole-Evans on the islands to British military intelligence in London the details of troop deployment, bombing raids, radar bases and military activities.<ref name="Falk">Template:Cite web</ref>
Major contributions to communications in the fields of automated message systems and packet radio were made by amateur radio operators throughout the 1980s. These computer controlled systems were used for the first time to distribute communications during and after disasters.<ref name="fcc hist">Template:Cite web</ref>
By international agreement in the past, amateur radio operators were required to have a qualification endorsement of Morse Code proficiency to use frequencies below 30 MHz. In 2003 the World radiocommunications conference (WRC) met in Geneva, Switzerland, and Morse code is no longer an internationally required qualification for an amateur radio license.<ref name=nocode>Template:Cite web</ref> This does not preclude any licensing authority from requiring the proficiency of Morse code to obtain an amateur radio license, however countries are no longer obliged by international treaty to require Morse code proficiency. Current rules in the United States<ref name="fcc rules">Template:Cite book</ref> require some Morse code proficiency to allow operation on frequencies below 30 MHz. Proceedings by the FCC are currently underway regarding whether the requirement will be kept. Discussions regarding whether it should engender lively debate among amateur radio operators.
Amateur radio activities and practices
Amateur radio operators enjoy personal two-way communications with friends, family members, and complete strangers, all of whom must also be licensed. They support the larger public community with emergency and disaster communications. Increasing a person's knowledge of electronics and radio theory as well as radio contesting are also popular aspects of amateur radio.
Radio amateurs use a variety of modes of transmission to communicate with one another. Voice transmissions are the most common way hams communicate with one another, with some types of emission such as frequency modulation (FM) offering high quality audio for local operation where signals are strong, and others such as single side band (SSB) offering more reliable communications when signals are marginal and using smaller amounts of bandwidth.
Radiotelegraphy using Morse code remains surprisingly popular, particularly on the shortwave bands and for experimental work on the microwave bands, with its inherent signal-to-noise ratio advantages. Morse, using internationally agreed code groups, can also facilitate communications between amateurs who do not share a common language. Radiotelegraphy is also popular with home constructors as CW-only transmitters are simple to construct when compared to voice transmitters.
The explosion in personal computing power has led to a boom in digital modes such as radio teletype, which a generation ago required cumbersome and expensive specialist equipment. Hams led in the development of packet radio, which has since been augmented by more specialized modes such as PSK31 which is designed to facilitate real-time, low-power communications on the shortwave bands. Other modes, such as the WSJT suite, are aimed at extremely marginal propagation modes including meteor scatter and moonbounce or Earth-Moon-Earth (EME).
Similarly, fast scan amateur television, once considered rather esoteric, has exploded in popularity thanks to cheap camcorders and good quality video cards in home computers. Because of the wide bandwidth and stable signals required, it is limited in range to at most 100 km (about 62 miles) in normal conditions.
The modes noted above are typically used in direct, radio-to-radio communication. On VHF and higher frequencies, automated relay stations, or repeaters, are used to increase range. Repeaters are usually located on the top of a mountain or tall building. A repeater allows the radio amateur to communicate over hundreds of square miles using only a relatively low power hand-held transceiver. Repeaters can also be linked together, either by use of other amateur radio bands, by wireline, or, increasingly via the Internet.
While many hams just enjoy talking to friends, others pursue interests such as providing communications for a community emergency response team; antenna theory; communication via amateur satellites ; disaster response; severe weather spotting; DX communication over thousands of miles using the ionosphere to refract radio waves; the Internet Radio Linking Project (IRLP) which is a composite network of radio and the Internet; Automatic Position Reporting System (APRS), which is a system of remote positioning that uses GPS; Contesting; the sport of Amateur Radio Direction Finding; High Speed Telegraphy; or low-power operation.
Most hams have a room or area in their home which is dedicated to their radio and ancillary test equipment, known as the "shack" in ham slang.
Many hams enjoy meeting each other in person at events held in various locations. These annual events are generally known as a hamfest with the largest being held in Dayton Ohio.
QSL cards
Traditionally radio amateurs exchange QSL cards with other stations, to provide written confirmation of a conversaton (QSO). These are required for many amateur operating awards, and many amateurs also enjoy collecting them simply for the pleasure of doing so.
DXing
Template:See Many amateurs enjoy trying to contact stations in as many different parts of the world as they can on shortwave bands, or over as great a range as possible on the higher bands, a pursuit which is generally known as DXing.
Awards
The number of operating awards available is literally in the thousands. The most popular awards are the Worked All States award, usually the first award amateurs in the United States aim for, the Worked All Continents award, also an entry level award on the shortwave bands, and the more challenging Worked All Zones and DX Century Club (DXCC) awards. DXCC is the most popular awards programme, with the entry level requiring amateurs to contact 100 of the (as of 2005) 335 recognized countries and territories in the world, which leads on to a series of operating challenges of increasing difficulty. Many awards are available for contacting amateurs in a particular country, region or city.
DX-peditions
Image:C5Z dx-pedition.jpg Certain parts of the world have very few radio amateurs. As a result, when a station with a rare ID comes on the air, radio amateurs flock to communicate with it. Often amateurs will travel specifically to a country or island, in what is known as a DX-pedition, to activate it. Big DX-peditions can make as many as 100,000 individual contacts in a few weeks.
Special event stations
Many amateurs also enjoy contacting the many special event stations on the air. Set up to commemorate special occurrences, they often issue distinctive QSLs or certificates. Some use unusual prefixes, such as the call signs with "96" that amateurs in the US State of Georgia could use during the 1996 Atlanta Olympics, or the OO prefix used by Belgian amateurs in 2005 to commemorate their nation's 175th anniversary. Some events are held annually such as Guides on the Air and Jamboree on the Air. Many amateurs decorate their radio "shacks" with these certificates.
Contesting
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Contesting (also known as radiosport) is a competitive activity pursued by amateur radio operators. In a contest, an amateur radio station, which may be operated by an individual or a team, seeks to contact as many other amateur radio stations as possible in a given period of time and exchange information. Rules for each competition define the amateur radio bands that may be used and the kind of information that must be exchanged in each contact. These contacts contribute to a score by which stations are ranked. Each competition is sponsored separately and has its own set of rules. Contest sponsors publish the results in magazines and on web sites. Over time, the number and variety of radio contests has increased, and many amateur radio operators today pursue the sport as their primary amateur radio activity.
Round table discussion groups
Many Amateur radio operators enjoy participating in round table discussion groups or "Rag Chew Sessions" on the air. These discussion groups have been a mainstay of Amateur radio since its inception.
Round table discussion groups are often configured where the conversation passes from one participant to another. The participants spend time developing and presenting their thoughts as the conversation passes from one person to another much as conversation would flow at a dinner table after a good meal. The conversation usually revolves around do-it-yourself experimentation; repairs; and topics related to radio, computers and electronics; however there is no limit to their scope.
Portable operations
Image:Sm0 4s7ab.jpg Licensed amateurs often take portable equipment with them when travelling, whether in their luggage or fitted into their cruising yachts, caravans or other vehicles. On long-distance expeditions and adventures such equipment allows them to stay in touch with other amateurs, reporting progress, arrival and sometimes exchanging safety messages along the way.
Many hams at fixed locations are pleased to hear directly from such travellers. From in a yacht in mid-ocean or a 4x4 inside the Arctic Circle, a friendly voice and the chance of a kind fellow-enthusiast sending an e-mail home is very well received.
See maritime mobile amateur radio for further details about operation in this way at sea.
Some countries' amateur radio licences allow for phone patching, or the direct connection of amateur transceivers to telephone lines. Thus a traveller may be able to call another amateur station and, via a phone patch, speak directly with someone else by telephone.
Emergency communications
Template:See In times of crisis and natural disasters, ham radio is often used as a means of emergency communication when wireline and other conventional means of communications fail. Recent examples include the 2001 attacks on the World Trade Center in Manhattan, the 2003 North America blackout and Hurricane Katrina in September, 2005, where amateur radio was used to coordinate disaster relief activities when other systems failed. Amateur radio operators who are involved in emergency communications often belong to a national or local emergency club, such as ARES and RACES in the United States, AREC in New Zealand, and RAYNET in the United Kingdom.
Low power operations
Template:See There is a sub-culture of amateur radio operators who concentrate on building and operating radios that operate at low power. This activity goes by the name QRP which is an international Q code for "reduce power". QRP operators use less than 5 watts output on Morse Code and 10 watts on voice.
VHF, UHF and microwave operation
The Amateur radio high bands are the VHF, UHF and microwave frequencies above 30 MHz. While many radio amateurs use VHF or UHF frequencies primarily for local communications, other amateurs build up more sophisticated systems to communicate over as wide a distance as possible. One technique some amateur radio operators use to communicate over long distances is to use the surface of the moon as a passive reflector. Earth-Moon-Earth operation, or EME, allows communications between any two places on the earth which can see the moon at the same time.
Amateur radio licensing
In most countries, amateur radio operators are required to pass an exam displaying knowledge and understanding of key concepts. This is in contrast to other personal radio services such as CB radio, General Mobile Radio Service, Multi-Use Radio Service, or Family Radio Service / PMR446 that are unlicensed and more heavily restricted. In return, hams are granted operating privileges in larger segments of the radio frequency spectrum using a wide variety of communication techniques that would otherwise be unavailable to them.
Getting started
Many people get started in amateur radio by finding a local club. Clubs can provide information about licensing in their respective area, local operating practices and technical advice. (See Category: Amateur radio organizations)
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. In the majority of countries, there are a series of exams available, progressively more challenging and granting progressively more privileges in terms of frequency availability, power output, and permitted experimentation.
In some countries, however, amateur licensing is either inordinately bureaucratic (e.g. India), or amateurs must undergo difficult security approval (e.g. Iran). A handful of countries, currently only Yemen and North Korea, simply do not permit their citizens to operate amateur radio stations, although in both cases a limited number of foreign visitors have been permitted to obtain amateur licenses in the past decade.
A further difficulty occurs in developing countries, where licensing structures are often copied from European countries and annual license fees can be prohibitive in terms of local incomes. This is a particular problem in Africa and to a lesser extent in poorer parts of Asia and Latin America. Small countries or those with weak administrative structures may not have a national licensing scheme and may require amateurs to take the licensing exams of a foreign country in lieu.
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 knowledge and telegraphy skill.
When licensed
After licensing, a radio amateur is typically issued a callsign by their local government. This callsign is unique to the operator and is often a source of pride. The holder of a callsign uses it on the air to legally identify the operator or station during any and all radio communication<ref>Template:Cite web</ref>
Privileges of the amateur
In contrast to most commercial and personal radio services, most radio amateurs are not restricted to using type-approved equipment, allowing them to home-construct or modify equipment in any way so long as they meet national and international standards on spurious emissions.
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.
Although permitted power levels are moderate by commercial standards, they are sufficient to enable cross-continental communication even with the least effective antenna systems, and world-wide communications at least occasionally even with moderate antennas. Power limits vary from country to country, for the highest license classes for example, 2 kilowatts in most countries of the former Yugoslavia, 1.5 kilowatts in the United States, 1 kilowatt in Belgium, 750 watts in Germany, 400 watts in the United Kingdom, 300 watts in Italy and 150 watts in Oman. Lower license classes are usually restricted to lower power limits; for example the lowest license class in the UK has a limit of just 10 watts.
Some suggest that the amateur portion of the radio spectrum is like a national park: something like the Yosemite of natural phenomenon. Through the licensing requirement, radio amateurs become like trained national park guides and backpackers. Where the backpackers and guides know about the beauty of the parks as well as the rules of engagement with wildlife in the park system, radio amateurs learn to appreciate and respect the beauty of the very limited electromagnetic space and the rules of engagement of human interaction within that space. In contrast, all of humanity benefits from the radio spectrum's existence, although it can not actually be seen.
In the United States, the Federal Communications Commission licenses operators in the Amateur Service as part of a mission that includes radio experimentation, public service, and the maintaining of a trained pool of technically-oriented operators. In exchange for learning the information needed to pass the federal test, licensed operators are allowed to use some 1300 distinct modes of communications, at power levels ranging from microwatts to thousands of watts, effective radiated power.
A distinguishing privilege of amateur radio is the ability to use a Variable-frequency oscillator (VFO) for controlling the frequencies of communications. Usually, the only other radio services granted the use of a VFO are military. All others, (aircraft; police; fire; Citizens' band; and business radio services,) are restricted to designated channelized frequencies. The privilege to use a VFO is granted to Amateur radio operator only after he or she has demonstrated the understanding of the frequency ranges under which the license is granted by taking an examination at the time of licensing. Amateur radio operators also are allowed to operate "out of band" in certain situations. For example, facilitating emergency communications or participation in the Military Affiliate Radio System (MARS) to exchange radio telegrams on military frequencies.
International licensing and operation
Template:See When traveling abroad, the visitor must hold a reciprocal license with the country in which she or he wishes to operate. 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.
Governance and amateur radio societies
The International Telecommunication Union (ITU) governs the allocation of communications frequencies world-wide, with participation by each nation by representation from their 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 concentrate modes of transmission in specific frequency allocations within IARU guidelines, to ensure most effective use of available spectrum.
Many countries have their own national (non-government) amateur radio society that coordinates with the communications regulation authority for the benefit of all 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, and Radio Amateurs of Canada.
Band plans and frequency allocations
Template:See Through ITU agreement, frequencies have been set aside for amateur radio. From there, national telecommunication agencies decide which of the international allocations can be used within their borders. National amateur radio societies often have band plans to further divide those allocations, often by use.
Amateur radio in popular culture
Template:See Amateur radio can be found throughout popular culture as a plot device. An example from Hollywood is the 2000 film Frequency. In it, the two main characters, a father and son (played by Dennis Quaid and Jim Caviezel respectively), communicate via amateur radio after the father has died. This is, of course, impossible, but makes a fine plot device. A wealth of additional information may be found at the main article link shown above.
See also
- Organizations
- Technology
- Antenna (radio) all of types and sizes
- Transceivers (integrated receiver and transmitter), the centerpiece of most modern stations.
- Vibroplex - semi-automatic telegraph key
- APRS - Automatic Position Reporting System, a very popular digital mode that transmits your current position.
Publications
- The ARRL Handbook for Radio Communications 2006 - ISBN: 0-87259-949-3
- RSGB Radio Communication Handbook - 8th Edition - ISBN: 0-90508-609-1
- Ham Radio Operator's Guide - ISBN: 0-79061-238-0
- 200 Meters & Down, The Story of Amateur Radio - ISBN: 0-87259-001-1
- Hello World : A Life in Ham Radio - ISBN: 1-56898-281-X
- Moran of Kathmandu: Pioneer Priest, Educator and Ham Radio Voice of the Himalaya - ISBN: 9-74829-972-4
- YASME--The Danny Weil and Colvin Radio Expeditions - ISBN: 0-87259-893-4
- HF Amateur Radio - ISBN: 1-87230-975-5
Country specific
Australia
- Foundation License Manual, The: Your Entry into Amateur Radio - ISBN: 0-97583-420-7
Canada
- Canadian Amateur Study Guide for the Basic Qualification, The - Fifth Edition, Second Printing - ISBN: 1-89540-008-2
Great Britain
- Foundation Licence - Now ! - ISBN: 1-87230-980-1
United States
- Now You're Talking!, 5th Edition - ISBN: 0-87259-881-0
- FCC Rule Book, Tenth Edition - ISBN: 0-87259-510-2
- Ham Radio For Dummies - ISBN: 0-76455-987-7
References
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