04593389 is referenced by 83 patents and cites 5 patents.

A telephone which can receive and transmit voice and asynchronous data simultaneously is provided. A signalling circuit provides signals indicating the request for a communication link or requesting a communication link to a predetermined location. A transceiver circuit synchronously receives and transmits frames of digital data bits representing data, voice and signalling information. A voice digitizer circuit converts the received frames of digital bits to an analog output and converts a received voice signal to a digital voice output. An interface circuit is used to interface between an asynchronous data source and the synchronous transceiver circuit. The telephone is line powered by utilizing D.C. isolating transformers to power both voice and data circuitry.

Title
Simultaneous voice and asynchronous data telephone
Application Number
6/625871
Publication Number
4593389
Application Date
June 28, 1984
Publication Date
June 3, 1986
Inventor
Stephen H Kelley
9226 Knoll Crest Loop, Austin, 78759
TX, US
Henry Wurzburg
12506 Wistful Cove, Round Rock, 78664
TX, US
IPC
H04J 3/12
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