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Amateur radio (also called ham radio) describes the use of radio frequency spectra for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation and emergency communication. The term "amateur" is used to specify "a duly authorised person interested in radioelectric practice with a purely personal aim and without pecuniary interest;"〔(【引用サイトリンク】url=http://www.itu.int/dms_pub/itu-s/oth/02/02/S02020000204501PDFE.pdf )〕 (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.). The amateur radio service (''amateur service'' and ''amateur satellite service'') is established by the International Telecommunication Union (ITU) through the International Telecommunication Regulations. National governments regulate technical and operational characteristics of transmissions and issue individual stations licenses with an identifying call sign. Prospective amateur operators are tested for their understanding of key concepts in electronics and the host government's radio regulations. Radio amateurs use a variety of voice, text, image, and data communications modes and have access to frequency allocations throughout the RF spectrum to enable communication across a city, region, country, continent, the world, or even into space. Amateur radio is officially represented and coordinated by the International Amateur Radio Union (IARU), which is organized in three regions and has as its members the national amateur radio societies which exist in most countries. According to an estimate made in 2011 by the American Radio Relay League, two million people throughout the world are regularly involved with amateur radio. About 830,000 amateur radio stations are located in IARU Region 2 (the Americas) followed by IARU Region 3 (South and East Asia and the Pacific Ocean) with about 750,000 stations. A significantly smaller number, about 400,000, are located in IARU Region 1 (Europe, Middle East, CIS, Africa). ==History== (詳細は The origins of amateur radio can be traced to the late 19th century, but amateur radio as practiced today began in the early 20th century. The ''First Annual Official Wireless Blue Book of the Wireless Association of America'', produced in 1909, contains a list of amateur radio stations. This radio callbook lists wireless telegraph stations in Canada and the United States, including 89 amateur radio stations. As with radio in general, amateur radio was associated with various amateur experimenters and hobbyists. Amateur radio enthusiasts have significantly contributed to science, engineering, industry, and social services. Research by amateur operators has founded new industries, built economies, empowered nations,〔(''Role of Amateur Radio in Development Communication of Bangladesh.'' Information & Communication Technology for Development. By Bazlur Rahman )〕 and saved lives in times of emergency. Ham radio can also be used in the classroom to teach English, map skills, geography, math, science and computer skills. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Amateur radio」の詳細全文を読む スポンサード リンク
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