Amateur radio
Non-commercial use of the radio spectrum
Amateur radio, also known as Ham radio, is the use of specific bands and frequencies within the radio spectrum for non-commercial communication, technical experimentation, self-training, recreation, radiosport, contesting, and emergency communications. A surge of popular interest in radio experimentation in the early 20th century necessitated that parts of the radio spectrum be allocated to non-professionals. In 1927 a radio amateur was defined as "a duly authorized person interested in radioelectric practice with a purely personal aim and without pecuniary interest", meaning without monetary or similar reward.
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