Advertisement

Amateur radio

From Academic Kids

Amateur radio, commonly called "ham radio", is a hobby enjoyed by many people throughout the world (as of 2004 about 3 million worldwide, 60,000 in UK, 70,000 in Germany, 5,000 in Norway, 57,000 in Canada, and 700,000 in the USA). A holder of an Amateur Radio license has studied and passed required tests in his or her country and been issued a call sign by its government. This call sign is unique to the operator and is often a source of pride. The holder of a call sign uses it on the air to legally identify all voice and data communications. Amateur Radio should not be confused with CB radio, General Mobile Radio Service or Family Radio Service, which are limited to voice operation only, lower power limits, fewer frequency allocations, and are unlicensed in most countries.

According to the Federal Communications Commission, the agency that regulates radio and telecommunications in the United States, amateur radio serves the following purposes:

  • Promotion and enhancement of the Amateur Radio Service as a voluntary noncommercial public communications service.
  • Continual advancement of the art of radio communication.
  • Expansion of the reservoir of trained radio operators and electronic experts.
  • Enhancement of international goodwill at the grass roots level.

The full regulations from the FCC are found in Part 97 (http://www.access.gpo.gov/nara/cfr/waisidx_04/47cfr97_04.html/) of the FCC regulations

Contents

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. International Amateur Radio Union (IARU) member nations may choose to further limit specific frequency allocations within IARU guidelines.

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 (WIA), formed in 1910; other notable early societies are the Radio Society of Great Britain founded in 1913 the American Radio Relay League created in 1914 and Radio Amateurs of Canada. National societies also cooperate through the IARU.

Band plans and frequency allocations

Through ITU agreement bandwidth has been set aside for amateur transmissions. Amateurs use a variety of transmission modes, including Morse code, radio teletype, data, and voice. Specific frequency allocations are a matter of record and vary from country to country and region to region, but the frequency allocations in the USA are:


The ARRL has a detailed band plan (http://www.arrl.org/FandES/field/regulations/bandplan.html) for US hams on their website. For ITU region 2, RSGB's band plan (PDF) (http://www.rsgb.org/bandplans/bandplans.pdf) will be more definitive. RAC has a chart showing the frequencies available to amateurs in Canada (http://www.rac.ca/regulatory/allband.htm).

An other form of amateur radio in the US is LowFER.

Use and available activities

Licensed 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 this radio service. A good way to get started in Ham Radio is to find a club in your area to answer your questions and provide information on getting licensed and then getting on the air.

Ham Radio offers the licensed operators a variety of radio modes that help to ensure reliable communications during and after disasters. Many of these rely on the "simplex communication" mode, that is direct, radio-to-radio, avoiding the problems associated with networks that might fail. In Ham Radio simplex communications would allow skilled radio operators to talk across town on VHF or UHF frequencies, or across the world on the HF (shortwave) bands of frequencies. Hams also have another powerful tool available, repeaters. Repeaters are radio relay devices usually located on the top of a mountain or tall building. A repeater allows the licensed Ham to have radio coverage for hundreds of miles from just a small handheld or mobile two-way radio.

Within amateur radio, one can pursue interests such as providing communications for a community emergency response team; antenna theory; satellite communication (see AMSAT and OSCAR series satellites); disaster response; Skywarn; packet radio (using data transmission protocols similar to that used on the Internet, but via radio links); DX communication over thousands of miles using the ionosphere to refract radio waves; Internet Radio Linking Project (IRLP) which is a composite network of radio signals and the Internet; Automated Position Reporting System (APRS), which is a radio-to-radio network of amateur radio and the Global Positioning System, radio contests http://www.contesting.com and super low-power or QRP operation.

QSL cards, awards, and contesting

One of the many exciting activities of ham radio is the DX-pedition. Radio amateurs collect QSL cards from other stations, indicating the continents and regions which they have contacted. Certain zones 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. To take advantage of this phenomenon, groups of hams transport radio equipment into a remote country or island (such as normally uninhabited Bouvet Island, which has the rare callsign prefix 3Y). These expeditions can help hams quickly achieve a communication award such as a DXCC. To obtain the DXCC award a ham needs confirming QSL cards from hams in 100 countries around the world.

Missing image
C5Z_dx-pedition.jpg
A group of Amateur Radio operators during DX-pedition to The Gambia in October 2003.

Many other awards are also available. Some, such as working 100 islands, including at least one from every continent, or contacting the 40 radio "zones" that the world is unofficially divided into, are fairly difficult. While working every U.S. state can be done in a few months of casual operation, confirming every county can take a decade or more. Other awards, such as contacting all 10 U.S. radio districts, are quite easy. In addition, every year there are 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 Georgians could use during the 1996 Atlanta Olympics. (Collecting prefixes is another aspect of the hobby.) Many amateurs decorate their radio "shacks" with these certificates. Not surprisingly, they are called "wallpaper."

Contesting is another activity that has garnered interest in the ham community. During a period of time (normally 24 to 48 hours) a ham tries to successfully communicate with as many other hams as possible. In the U.S., one such event is Field Day, held in the fourth full weekend in June. The contesting amateur may concentrate on just DX stations, or only on stations powered by emergency generation equipment or running on batteries, which is meant to simulate hurricane or other emergency disaster conditions. Some contests may or may not be limited in allowable modes of transmission, such as voice or Morse. A number of hams join together to form contest teams. This popular team event, popular in the US, is now gathering further popularity in Europe, with contest teams taking on amusing names such as The Barking Mad Contest Group, or The Northern Lights and even the Gentlemans Contesting Group. Sometimes amusing phonetics are used with the callsigns to get attention and talk to more stations during the contest, such as the DuPage County (IL) Amateur Radio Club's callsign W9DUP - "Whiskey 9 Dirty Under Pants".

Weak-signal and low-power activities

Some radio amateurs (hams) use VHF or UHF frequencies to bounce their signals off the moon. The return signal is heard by many other hams who also do EME (earth-moon-earth). The antennas normally required can range from parabolic dishes of up to 10 metres in diameter to an array of directional (usually yagi type) antennas.

Digital signal processing has revolutionised weak signal communications by radio amateurs. Using freely available software tools and modern computers, radio amateurs can results they would only have dreamed of only 10 years earlier. For example, reflecting signals off the moon, once the realm of only the very best equipped amateur stations, has become feasible for much more modest stations. Instead of a large dish or an array of 8 antennas, it has become possible for stations with 400 to 1000 watts transmit power and a single well designed antenna to make contacts using moonbounce.

Other hams build large antenna arrays simply in order to make contacts over very long distances on upper frequencies like VHF (50 Mhz, and 144 Mhz) and above (microwave) where the average range for these frequencies is line of sight. A VHF signal transmitted from a walkie-talkie (or as hams call it a Handi-talkie or HT for short) will typically travel about 3-5 miles depending on terrain. With a large antenna system like a 12 element directional yagi, and higher power (typically 100 or more watts) contacts over hundreds of miles are common. They are pushing the limit of the frequencies usual characteristics looking to learn and experiment with radio technology.

Hams also build large antenna system to take advantage of "band openings" where due to various natural occurrences, radio emissions can travel well over their normal characteristics. There are numerous causes for these band openings and many hams listen for hours to take advantage of their rare manifestations.

Some openings are caused by intense excitement of the upper atmosphere, known as the ionosphere. These band openings can also be caused by weather phenomenon known as an inversion layer, where cold air traps hot air beneath it, which forces the radio emission to travel over long weather layers. Radio signals can travel hundreds of miles because of these weather layers.

Some hams are fascinated to see how much they can achieve with very low power. Signals on the order of 5 watts or less are heard all over the world by these QRP (low power) operators. Some amateurs never use more than a few watts of transmit power. By setting up efficient antennas and using expert operating techniques, they can make regular international contacts and get immense satisfaction from their achievements.

Maritime mobile, mobile and portable operations

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 static-based hams are very 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. With a phone patch, which connects the transmitter/receiver to the phone line for phone communications, travellers could radio another amateur to speak with someone else over the telephone lines. [1] (http://www.arrl.org/FandES/field/regulations/phone-patch.html)

Missing image
Sm0_4s7ab.jpg
Mr Kamal Edirisinghe from Sri Lanka operating portable Amateur Radio station south of Stockholm, Sweden

Past, present, and future

Despite all these exciting specialties, many hams enjoy the informal contacts, long discussions or "rag-chews", or round table "nets", whether by voice transmission (SSB, AM, or FM), CW (morse telegraphy), or one of the digital modes (RTTY, PSK31, and others).

Even with the advent of the Internet (offering email, music, broadcast audio, video, voice over IP) ham radio is not diminishing in countries with advanced communications infrastructure. Amateur radio remains strong even today, as figures from the American Radio Relay League will prove. This may be partly because Hams enjoy communicating using the most minimalist simple hardware possible, as well as finding the most technically advanced way, advancing the art of radio communication at both ends, frequently beyond what professionals are willing to try and risk.

Voice over IP (VoIP) is also finding its way into Amateur Radio. Programs like Echolink tie hams with computers into ham radio repeaters across the globe. The Internet Radio Linking Project (IRLP) (http://www.irlp.net/) utilizes VoIP to tie repeaters together directly by user command. This nascent use is finding applications in emergency services as well, as an alternative to expensive (and sometime fallible) trunking systems.

In times of crisis and natural disasters, ham radio may be the only surviving means of communication. It has been found all too often that both wire and cellular telephone systems either fail or are overloaded in times of crisis and radios dedicated to emergency services fare little better. In the United States, two organizations of amateur radio operators exist nationally for disaster communications. They are the Amateur Radio Emergency Service (ARES) and the Radio Amateur Civil Emergency Service (RACES). Typically a local radio club will have information on joining either or both. In areas where known disaster problems exist, amateur radio has a long-standing tradition of cooperation with local emergency services. Los Angeles County and the Disaster Communications Service (http://www.lacdcs.org/) exists as an example and a model.

On March 18, 1909, Einar Dessau used a short-wave radio transmitter which made him the first to broadcast as a ham radio operator.

More recently, on September 2, 2004, ham radio was used to inform weather forcasters with information on hurricane Frances live from the Bahamas. On December 26, 2004 a great tsunami across the Indian Ocean wiped out all communications with the Andaman Islands, except for a DXpedition that provided a critical link with the outside world to coordinate relief efforts.

Missing image
Andaman_dx-pedition.jpg
Mrs Bharathi Prasad using her call sign VU4RBI demonstrates Amateur Radio to local students in Port Blair, Andaman Islands, a couple of days before the 2004 Indian Ocean earthquake.

Amateur radio and innovation in telecommunications technology

Throughout its history, amateur radio has made significant contributions to science, industry, and the social services. The economic and social benefit derived from amateur radio research has founded new industries, built economies, empowered nations, and saved lives.

Amateur radio represents a unique research and development (R&D) environment that cannot be duplicated in the labs or research parks of either industry or the government. Existing at the intersection of the social, economic, cultural and scientific spheres, amateur radio leverages this position to invent and innovate from a unique perspective. Many now-commonplace communication technologies have their genesis in amateur radio.

However, the amateur radio service, or more specifically, the portion of the electromagnetic spectrum allocated to the activity, is under extreme pressure from the telecommunications industry. Recent exponential growth in commercial wireless communication systems has taxed existing commercial spectrum allocations, and industry is eager for expansion. Amateur radio spectrum is threatened. Ironically, many of the communication technologies used by these firms were initially developed within the field of amateur radio.

A new problem is the attempt by some companies to transmit the Internet over powerlines. Known as BPL, this technology can create significant radio static. While the U.S. Federal Communications Commission appears to be sympathetic to the industry, amateurs have been battling it. To date (2005) field trials by the industry have generally been unsuccessful in meeting radio pollution standards, and often discontinued after brief attempts to attract customers. The technology has also been under severe criticism in Europe. Given other transmission modes, the future of BPL appears very questionable.

To justify their quest for additional spectrum, industry lobbyists portray amateur radio as an anachronism, and characterize amateur bands, particularly in the UHF and microwave region, as underutilized. On the contrary, innovative communications research within the hobby is alive and well, and many of these new amateur projects utilize the higher-frequency bands sought after by industry. There is commercial interest in some of the new technologies currently under development within amateur radio, and amateur radio continues to contribute to the state of the radio art.

See http://highgate.comm.sfu.ca/thesis for a comprehensive discussion of this topic.

Operating Abroad

When traveling abroad, you must hold a reciprocal license with the country in which you wish 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.

CEPT

Member Nations of the European Conference of Postal and Telecommunications Administrations (CEPT) all have the same radio-amateur reciprocal licensing requirements. This allows Amateurs to travel to and operate from most European countries without obtaining an additional licensee or permit for each country visited.

IARP

The International Amateur Radio Permit (IARP) allows For operation in certain countries of the Americas. The IARP allows hams to operate without the need to obtain a license or permit to operate from a country. To operate a station in a Inter-American Telecommunication Commission (CITEL) member nation you must obtain an IARP. The CITEL agreement allows an IARP to be issued by a member-society of the International Amateur Radio Union (IARU). The permit describes its authority in four different languages.

Other Parts of the World

In other parts of the world where CEPT nor IARP apply and the country you are visiting has not entered bilateral or multilateral reciprocal operating agreement with your licensing government, you must follow that country's guidelines to obtain a reciprocal license. For most countries, you will need to file an application several months before you plan on operating. Along with your application, you will usually need to send a copy of your original Amateur Radio License, a copy of your passport and an itinerary of where and when you will operate your station. Some countries may also require a processing fee. In some rare cases you may have to obtain a full amateur raio license and callsign from the country you will be visiting.


Tools and appliances

See also

Morse code, electromagnetism, Electromagnetic radiation, Q Code, SSTV, country codes, callsigns, PSK31, ARISS, APRS, TV/FM DX

Major clubs, societies, and associations

External links

Finding a club and governmental licensing links

  • Locate a club (http://www.dxzone.com/catalog/Ham_Radio/Clubs) in your country or in your state.
  • Contact information (http://www.iaru.org/iaru-soc.html) for on the Amateur Radio society of your country. They will provide all information on licensing terms and put you in touch with radio amateurs in your own town.

Club links

Amateur radio on the screen

Hollywood movies have also used Amateur Radio as a convenient and often fanciful part of their plot:

  • ALF (TV, 1986-1990) An Alien Life Form -- ALF -- crash lands at the Los Angeles home of Willie Tanner, an Amateur Radio Operator.
  • Bob the Builder: A Christmas to remember (2001) Bob and his brother, Tom, use ham radio to communicate. Bob has an antenna on the side of his yard's office, which is not seen in the series. Tom lives in the Arctic.
  • Contact (1997) starring Jodie Foster playing Dr. Eleanor Ann 'Ellie' Arroway, opens with the heroine operating a ham radio transceiver as a child. She later becomes a researcher working in SETI.
  • Fleksnes A Norwegian TV series from 1970's about a radio amateur spending much time at his station.
  • The French Atlantic Affair (1979) A 3-part ABC miniseries from the Ernest Lehman novel (1977). A hijacked cruise ship story where a smuggled-aboard ham radio is the only independent contact with the outside world.
  • Frequency (2000) starring Jim Caviezel playing 'John Sullivan', and Dennis Quaid playing 'Frank Sullivan', has the fanciful plot of a father ('Frank') and son ('John') using Amateur Radio to communicate after the father has died.
  • If All the Guys in the World (original title Si tous les gars du monde... (http://fr.wikipedia.org/wiki/Si_tous_les_gars_du_monde_(film))) (1957), is a French film largely devoted to the Art of Amateur Radio. Jean Louis, a young radio enthusiast who lives in Paris, receives an SOS message sent from a ship in the high seas. Through his modest radio station, and with the help of fellow radio amateurs around the world he tries to prevent a major catastrophe from happening. This is the first movie appearance of the celebrated French actor Jean Louis Trintignant.
  • Men of Boys Town (1941), is the sequel of Boys Town (1938), starring Spencer Tracy and Mickey Rooney. In this movie Whitey Marsh (Mickey Rooney) has frequent conversations with his friend Pee Wee (Bobs Watson) over the amateur radio waves. Whitey transmits from the home of his adoptive parents, while Pee Wee is at the amateur radio club in Boys Town.
  • Qualcuno in Ascolto (1988) (released in the U.S. in 1989 as High Frequency), in which a young ham and a satellite-relay operator become witnesses to a murder and must find a way to warn the murderer's next target.
  • Tony Hancock's 1960 BBC TV episode The Radio Ham, in which he plays an incompetent ham radio operator, has remained popular in the U.K. and has played a small part in keeping the memory of ham radio's heyday alive.
  • The Sweet Hereafter (1997) starring Ian Holm playing 'Mitchel Stephens', features a scene where a man is sitting at a table, holding a pair of communication headphones up to one ear. On the wall is a plastic QSL card holder full of cards.

Honorable Mention:

  • Star Wars (1977) during the battle of the death star, the pilots communicate with each other over the radio using what sounds like SSB modulation, which is frequently used in the Amateur HF band. This is particularly obvious if you listen for the voice distortion characteristic of SSB when flipping between one character speaking and a character listening in another location over the radio.
  • THX-1138 (1971) In the directors commentary on the DVD release of this movie, George Lucas and his sound engineer Walter Murch speak of how they used the voice distortion characteristics of SSB modulation specifically to achieve a means of clearly distinguishing different voices. To produce the effect they used coupled an SSB transmitter to a receiver and varied the receiver tuning to modulate and distort the audio.cs:Radioamatrstv

da:Radioamatr de:Amateurfunkdienst eo:Amatora radio fr:Radioamateur it:Radioamatore nl:Radio-amateur ja:アマチュア無線 no:Amatrradio pl:Krtkofalarstwo pt:Radioamadorismo sr:Радио-аматеризам fi:Radioamatri th:วิทยุสมัครเล่น zh:业余无线电

Navigation

Academic Kids Menu

  • Art and Cultures
    • Art (http://www.academickids.com/encyclopedia/index.php/Art)
    • Architecture (http://www.academickids.com/encyclopedia/index.php/Architecture)
    • Cultures (http://www.academickids.com/encyclopedia/index.php/Cultures)
    • Music (http://www.academickids.com/encyclopedia/index.php/Music)
    • Musical Instruments (http://academickids.com/encyclopedia/index.php/List_of_musical_instruments)
  • Biographies (http://www.academickids.com/encyclopedia/index.php/Biographies)
  • Clipart (http://www.academickids.com/encyclopedia/index.php/Clipart)
  • Geography (http://www.academickids.com/encyclopedia/index.php/Geography)
    • Countries of the World (http://www.academickids.com/encyclopedia/index.php/Countries)
    • Maps (http://www.academickids.com/encyclopedia/index.php/Maps)
    • Flags (http://www.academickids.com/encyclopedia/index.php/Flags)
    • Continents (http://www.academickids.com/encyclopedia/index.php/Continents)
  • History (http://www.academickids.com/encyclopedia/index.php/History)
    • Ancient Civilizations (http://www.academickids.com/encyclopedia/index.php/Ancient_Civilizations)
    • Industrial Revolution (http://www.academickids.com/encyclopedia/index.php/Industrial_Revolution)
    • Middle Ages (http://www.academickids.com/encyclopedia/index.php/Middle_Ages)
    • Prehistory (http://www.academickids.com/encyclopedia/index.php/Prehistory)
    • Renaissance (http://www.academickids.com/encyclopedia/index.php/Renaissance)
    • Timelines (http://www.academickids.com/encyclopedia/index.php/Timelines)
    • United States (http://www.academickids.com/encyclopedia/index.php/United_States)
    • Wars (http://www.academickids.com/encyclopedia/index.php/Wars)
    • World History (http://www.academickids.com/encyclopedia/index.php/History_of_the_world)
  • Human Body (http://www.academickids.com/encyclopedia/index.php/Human_Body)
  • Mathematics (http://www.academickids.com/encyclopedia/index.php/Mathematics)
  • Reference (http://www.academickids.com/encyclopedia/index.php/Reference)
  • Science (http://www.academickids.com/encyclopedia/index.php/Science)
    • Animals (http://www.academickids.com/encyclopedia/index.php/Animals)
    • Aviation (http://www.academickids.com/encyclopedia/index.php/Aviation)
    • Dinosaurs (http://www.academickids.com/encyclopedia/index.php/Dinosaurs)
    • Earth (http://www.academickids.com/encyclopedia/index.php/Earth)
    • Inventions (http://www.academickids.com/encyclopedia/index.php/Inventions)
    • Physical Science (http://www.academickids.com/encyclopedia/index.php/Physical_Science)
    • Plants (http://www.academickids.com/encyclopedia/index.php/Plants)
    • Scientists (http://www.academickids.com/encyclopedia/index.php/Scientists)
  • Social Studies (http://www.academickids.com/encyclopedia/index.php/Social_Studies)
    • Anthropology (http://www.academickids.com/encyclopedia/index.php/Anthropology)
    • Economics (http://www.academickids.com/encyclopedia/index.php/Economics)
    • Government (http://www.academickids.com/encyclopedia/index.php/Government)
    • Religion (http://www.academickids.com/encyclopedia/index.php/Religion)
    • Holidays (http://www.academickids.com/encyclopedia/index.php/Holidays)
  • Space and Astronomy
    • Solar System (http://www.academickids.com/encyclopedia/index.php/Solar_System)
    • Planets (http://www.academickids.com/encyclopedia/index.php/Planets)
  • Sports (http://www.academickids.com/encyclopedia/index.php/Sports)
  • Timelines (http://www.academickids.com/encyclopedia/index.php/Timelines)
  • Weather (http://www.academickids.com/encyclopedia/index.php/Weather)
  • US States (http://www.academickids.com/encyclopedia/index.php/US_States)

Information

  • Home Page (http://academickids.com/encyclopedia/index.php)
  • Contact Us (http://www.academickids.com/encyclopedia/index.php/Contactus)

  • Clip Art (http://classroomclipart.com)
Toolbox
Personal tools