What is amateur radio | Amateur Radio In China
Amateur radio , also known as ham radio, is the use of radio frequency .Spectrum for purposes of non_commerical exchange of messages, wireless experimentation, self-training, private recreation, radio sprots, 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;" to differentiate it from commerical 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 radio regulations. National governments regulate technical and operational characteristics of transmissions and issue individual station licenses with a unique identifying call sign, which must be use...