Amateur Radio, also called by some "ham radio", is a hobby pass-time 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 licences its operators to use specific power levels or modes of communication.
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.
Frequency bands and modes of operation include:
- High Frequency (short-wave) through to microwave frequencies;
- 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)
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, provice, 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.
- International Amateur Radio Union (IARU)
- Wireless Institute of Australia (WIA) - the first national Amateur Radio society
- Amarican Radio Relay League (ARRL) - hobby society body for USA
- The Radio Amateur Satellite Corporation of North America