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WikepediaAmateur radio, often called Ham radio, is a hobby and public service enjoyed by about 3 million people[1] throughout the world. An amateur radio operator, also known as a ham or radio amateur, uses advanced radio equipment to communicate with other radio amateurs for public service, recreation and self-training.
Amateur radio operators enjoy personal wireless communications with friends, family members, and even complete strangers. They support the community with emergency and disaster communications. Increasing a person's knowledge of electronics and radio theory and radio contesting are also popular.
As used in this case, the legal term "Amateur" does not connote lack of skill, but simply indicates that the frequencies involved cannot be used for commercial purposes. In fact, a person usually has to pass an examination proving their skill before being licensed as an Amateur Radio Operator by their nation's government.
Radio amateurs use various modes of transmission to communicate. Voice transmissions are most common, with some such as frequency modulation (FM) offering high quality audio, and others such as single sideband (SSB) offering more reliable communications when signals are marginal and bandwidth is restricted.
Radiotelegraphy using Morse code remains popular, particularly on the shortwave bands and for experimental work such as Moonbounce, with its inherent signal-to-noise ratio advantages. Morse, using internationally agreed code groups, also allows communications between amateurs who speak different languages. It is also popular with homebrewers as CW-only transmitters are simpler to construct. For many years, demonstrating a proficiency in Morse code was a requirement to obtain amateur licenses for the high frequency bands, but following changes in international regulations in 2003, many countries have now dropped this requirement