Amateur radio

[1] The term "amateur" is used to specify "a duly authorized person interested in radioelectric practice with a purely personal aim and without pecuniary interest"[2] (either direct monetary or other similar reward); and to differentiate it from commercial broadcasting, public safety (such as police and fire), or professional two-way radio services (such as maritime, aviation, taxis, etc.).

Research by amateur operators has founded new industries,[5] built economies,[6] empowered nations,[7] and saved lives in times of emergency.

The amateur radio community subsequently began to reclaim the word as a label of pride,[15] and by the mid-20th century it had lost its pejorative meaning.

Many amateurs begin with a fascination with radio communication and then combine other personal interests to make pursuit of the hobby rewarding.

FM is recognized for its superior audio quality, whereas SSB is more efficient for long-range communication under limited bandwidth conditions.

Morse, using internationally agreed message encodings such as the Q code, enables communication between amateurs who speak different languages.

A similar "legacy" mode popular with home constructors is amplitude modulation (AM), pursued by many vintage amateur radio enthusiasts and aficionados of vacuum tube technology.

Demonstrating a proficiency in Morse code was for many years a requirement to obtain an amateur license to transmit on frequencies below 30 MHz.

[18][19] Modern personal computers have encouraged the use of digital modes such as radioteletype (RTTY) which previously required cumbersome mechanical equipment.

Automatic link establishment (ALE) has enabled continuous amateur radio networks to operate on the high frequency bands with global coverage.

[23] Repeaters are usually located on heights of land or on tall structures, and allow operators to communicate over hundreds of miles using hand-held or mobile transceivers.

Amateur radio satellites can be accessed, some using a hand-held transceiver (HT), even, at times, using the factory "rubber duck" antenna.

[28] Nets can allow operators to learn procedures for emergencies, be an informal round table, or cover specific interests shared by a group.

[29] Amateur radio operators, using battery- or generator-powered equipment, often provide essential communications services when regular channels are unavailable due to natural disaster or other disruptive events .

All countries that license citizens to use amateur radio require operators to display knowledge and understanding of key concepts, usually by passing an exam.

[45] The tests cover regulations, customs, and technical knowledge, such as FCC provisions, operating practices, advanced electronics theory, radio equipment design, and safety.

Morse Code is no longer tested in the U.S. Once the exam is passed, the FCC issues an Amateur Radio license which is valid for ten years.

In some countries, examinations may be offered only once or twice a year in the national capital and can be inordinately bureaucratic (for example in India) or challenging because some amateurs must undergo difficult security approval (as in Iran).

[46][47] Some developing countries, especially those in Africa, Asia, and Latin America, require the payment of annual license fees that can be prohibitively expensive for most of their citizens.

In North America, established amateurs who help newcomers are often referred to as "Elmers", as coined by Rodney Newkirk, W9BRD,[49] within the ham community.

Prefix "GM" & "MM" are Scotland, "GW" & "MW" are Wales, "GI" & "MI" are Northern Ireland, "GD" & "MD" are the Isle of Man, "GJ" & "MJ" are Jersey and "GU" & "MU" are Guernsey.

Prefix VA1 or VE1 is Nova Scotia, VA2 / VE2 is Quebec, VA3 / VE3 is Ontario, VA4 / VE4 is Manitoba, VA5 / VE5 is Saskatchewan, VA6 / VE6 is Alberta, VA7 / VE7 is British Columbia, VE8 is the Northwest Territories, VE9 is New Brunswick, VY0 is Nunavut, VY1 is Yukon, VY2 is Prince Edward Island, VO1 is Newfoundland, and VO2 is Labrador.

The last two or three letters of the call signs are typically the operator's choice (upon completing the licensing test, the ham writes three most-preferred options).

Non-exhaustive lists of famous people who hold or have held amateur radio call signs have also been compiled and published.

[59] Many jurisdictions (but not in the UK & Europe) may issue specialty vehicle registration plates to licensed amateur radio operators.

Amateur radio operators are encouraged both by regulations and tradition of respectful use of the spectrum to use as little power as possible to accomplish the communication.

National communications regulators have some liberty to restrict access to these bandplan frequencies or to award additional allocations as long as radio services in other countries do not suffer interference.

In a few cases, a national telecommunication agency may also allow hams to use frequencies outside of the internationally allocated amateur radio bands.

In the U.S., amateur radio operators providing essential communication needs in connection with the immediate safety of human life and immediate protection of property when normal communication systems are not available may use any frequency including those of other radio services such as police and fire and in cases of disaster in Alaska may use the statewide emergency frequency of 5.1675 MHz with restrictions upon emissions.

Encryption, for example, is not generally permitted in the Amateur Radio service except for the special purpose of satellite vehicle control uplinks.