| 摘要 |
PURPOSE:To urge a holder to make a response by connecting a channel of a held line to a telephone receiving amplifier upon reception of a voice signal from a caller to be held at a voice signal reception part. CONSTITUTION:When a central control part 4 detects a hold key press down signal of a key telephone 2-1, a system activates a voice source selection switch group 9 and a timer circuit 18. The control part 4 activates the switch group 9 by a count up signal from the circuit 18 and sends out a meassage to a station line. An input switch group 19 is turned on after sending said message, and the controller 4 is activated when a voice signal receiving part 20 receives the voice signal from a caller to be held and a held line channel connected to a receiving amplifier 12 of the telephone 2-1. |
