Amateur Radio, also called "ham radio", is a hobby followed by people in most countries of the world, using internationally coordinated, specifically designated, frequency bands. Each country or jurisdiction separately allocates the frequencies and licenses its operators to use specific power levels or modes of communication. They are issued a personal callsign that has letters reflecting their country's international callsign area, a number reflecting the state or region, and letters that particularize the callsign to them. See examples below.
Operators set up their stations normally in their homes, and use antenna systems suitable for their domestic situation. This may limit the frequency bands on which they can operate, as longer wavelength transmissions normally require larger antenna. Also, larger aerial arrays are needed to achieve higher transmission gain on higher frequencies. Vehicle mounted radios and antennas can also be used.
The portable and "can-do" nature of Amateur Radio has meant that Amateurs have often been first-responders during or just after major disasters, establishing links using procedures tested during regular "field days" or emergency exercises.
The International Space Station has an extensive suite of Amateur Radio equipment, as did the Russian MIR spacecraft. Most cosmonauts and astronauts are licensed operators.
Frequency bands and modes of operation include:
- High Frequency (short-wave) through to microwave frequencies;
- voice (referred to by ham operators as "phone")
- CW (Morse code)
- facsimile (fax over radio)
- television - slow-scan (similar to fax) and fast-scan (as for broadcast TV)
- satellites (over 20 operational in orbit)
- digital communications (various formats, the most common being PSK31)
Amateur Radio and Christianity
Until the widespread advent of telephone systems and the Internet in under-developed countries, Amateur Radio was widely used by missionary groups to communicate with people across the world. The missionaries operated their radios to talk to their home organsations and pass information to family members.
Additionally, they operated their radios to make contact with 'ordinary' Amateurs and give them highly prized "QSL contact card" with a country, state, province, or area where there were very few operators. Among Amateur Radio operators in developed countries the missionaries were, and still are, a very welcome and highly prized group of people, often supported with donations to support their ability to provide the much sought after QSL card, or through having someone manage their QSL card distribution. The usual form of exchange is for the Amateur to send a "green stamp" (a US$1 bill) in exchange for the QSL card. This pays for the mailing of the card, and normally left a little besides as a donation for the missionary.
Famous Amateur Radio operators and callsigns
- Walter Cronkite, CBS news anchorman - KB2GSD
- Hussein, King of Jordan - JY1
- Bhumiphol Adulayadej, King of Thailand - HS1A
- George Pataki, Governor of New York - K2ZCZ
- Barry Goldwater, Senator (US) (ret) - K7UGA/K3UIG
- Burl Ives, singer - KA6HVA
- Dr. Alex Comfort, author of "The Joy of Sex" - KA6UXR
- Donnie Osmond, entertainer - KA7EVD (lapsed)
- Marlon Brando aka Martin Brandeaux, actor - FO5GJ
- Chet Atkins, guitar player - WA4CZD
- Cliff Richard (Harry Webb), singer - W2JOF
- Joe Walsh, guitarist for The Eagles - WB6ACU
- Leon Schlesinger, creator of Porky Pig
- Radio: Radio waves, Electromagnetic wave, Radio frequency, AM/FM, modulation, amplitude, amplitude modulation (AM), frequency modulation (FM), or single-sideband modulation (SSB), Shortwave, Two-way radio, Portable radio, Walkie-talkie, Citizens band radio, Family Radio Service (FMS), General Mobile Radio Service (GMRS), Multi-Use Radio Service (MRS), Motorola, Marine VHF radio, History of radio
- Amateur Radio: Emergency communications, Amateur radio operator, Call sign, Selecting a radio, Amateur radio glossary, Amateur radio repeater, Base station, Amateur radio frequency allocations, Amateur bands, Amateur radio station, UHF (70-centimeter band), VHF (2-meter band), HF, Morse code, Telegraph, Mobile rig, Radio codes and alphabets, QSL card
- Antenna (radio): Antenna theory, Portable operation (amateur radio), Dipole antenna, Antenna tuner, Homebrew antennas, Coaxial cable, Balun, Packet radio, Propagation, Protecting your HT Antenna
- Radio Standards Organization: Radio legalities, Amateur radio license, Federal Communications Commission (FCC), American Radio Relay League, International Telecommunication Union (ITU)
- Cellular telephone: Mobile devices: Smartphones and tablets
Links: General Organizations
- International Amateur Radio Union (IARU)
- American Radio Relay League (ARRL) - hobby society body for USA, also involved in lobbying and emergency work
- Wireless Institute of Australia (WIA) - the first national Amateur Radio society
- The Radio Amateur Satellite Corporation of North America
- Quarter Century Wireless Association Organization of hams who have been licensed for 25+ years
- Christian Amateur Radio Fellowship
Links: Morse Code
- FISTS: International Morse Code Preservation Society
- Straight Key Century Club promotes manually-sent Morse code
Links: Emergency/Military Communications
- ARES Amateur Radio Emergency Services (branch of ARRL)
- RACES Radio Amateur Civil Emergency Services (branch of FEMA, activated by the President under War Powers Act)
- MARS Military Auxiliary Radio System (branch of US military)
- Skywarn (branch of NOAA/NWS, assists during weather disasters)