| 摘要 |
PURPOSE:To enable small size and economy, by enabling the exchange connection while multiplexing audio signal and video signal. CONSTITUTION:The television telephone terminal 1 consists of the telephone set 1a, television 1b, and multiplex unit 1c which multiplexes and separates the audio and video signals. The television telephone exchanger 20 consists of the switch matrix 29 which exchange-connects the multiplex signal of audio and video signals, intra-office trunk 27 used for the connection of television telephone terminals, detection circuit 21 to extract only the monitor control component included in the multiplex signal, transmission circuit 22 for the monitor control signal to the television telephone terminal, dial tone trunk 23, and common control unit 28. Further, the television telephone terminal 1 and the telephone exchanger 20 are linked with the transmission line 2. |
