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Apple QuickTime movie  |  2003-04-17  |  3.8 MB  |  256x192  |  10fps  |  55 seconds
Transcription: Unlike ordinary phones, which connect to the network by wire, a cellular telephone connects with the network by radio waves. A cellular telephone is actually a radio transmitter and receiver. These phones work with a network of low-powered radio antennas and transmitters. Each station serves a geographical area called a cell. When an antenna receives radio signals, signals from a cellular telephone, it sends them to a switching office, which in turn sends them by cable into the ordinary telephone network. The call is then routed to its destination. When a person in a moving car uses a cellular ...