Telephony class in the US Army, 1917

The use of devices for voice communication, for example, cellular and digital telephone systems.

See the Telephone article for a history of the telephone.


  • Cellular telephone systems - a system of telephone communications organized around a series of fixed site radio transceivers which each operate over a base area
  • Centrex telephone systems - an abbreviation of Central Exchange, a telephone switching system where the switching equipment is provided at a central exchange instead of at the customer's premises (such as in a private branch exchange)
  • Digital telephone systems - a telephone system which relies on digital, instead of analog, equipment for its switching and monitoring functions
  • Telephone switching systems - the different systems used by telephone operators to connect calls from one user to another


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Pages in category "Telephony"

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Media in category "Telephony"

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