T-carrier
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The T-carrier system is a member of the series of data-multiplexing carrier systems developed by AT&T Bell Laboratories for digital transmission of multiplexed telephone calls.
Left: A 66 block; center and right: Cabinets containing Smartjack network interface devices for T1 circuits
Telephone call
Videos
A telephone call, phone call, voice call, or simply a call, is the use of a connection over a telephone network between two parties for audio communication. To start a call, the calling party, the cal
An early 20th century candlestick telephone used for a phone call
An early 21st century mobile phone being used for a phone call
A modern Smartphone being used for a phone call
U.S. President Gerald Ford on the phone