| 摘要 |
PURPOSE:To allow a subscriber to use various voice encoding means properly upon occasion for communication, by providing a subscriber terminal with a composite CODEC. CONSTITUTION:When the subscriber lifts a handset 5, a signal control circuit 11 detects that and a dial tone from a signal generator 14 is sent out to the handset 5 through a synthesizing circuit 15. Once the subscriber operates one desired voice CODEC selection button 7 and inputs a called-subscriber's number with dial buttons 6, the control circuit 11 sets the composite CODEC 10 to a prescribed function to send out information on an encoding system and dial information to a digital subscriber line 3 through a multiplexing circuit 12 and a circuit terminating circuit 13. Althrough a switchboard which is not shown in a figure performs switching processing to start a call, but when an opposite subscriber terminal does not match with the encoding system, a signal showing that is sent back. In this case, the control circuit 11 lights on the mismatching lamp 8 of a display part 17 and the originating subscriber is informed of the mismatching by a sound. |
