| 摘要 |
PURPOSE:To apply the titled set to a subscriber line and an interphone line by providing a control means connecting an interphone set to a recorder when a call from the interphone set in detected in the automatic answering mode. CONSTITUTION:Call detection circuits 5, 6 detect respectively a call signal to an outdoor interphone set 1 and a telephone set 4. Switches 10, 11 connect the set 1 and an indoor interphone set 2 when a signal (a) is at H level, connects the set 1 and the recorder 12 when L, connect a trunk line terminal 3 and the telephone set 4 when the signal (b) is at H level and connects the terminal 3 and the set 12 when L. A mode designation switch 9 designates the automatic answering mode with ON state. A control circuit 7 discriminates the automatic answering mode depending on the state of the switch 9 and when a detection signal is obtained from the circuits 5, 6 during the automatic answering mode period, a holding tone transmission circuit 8 and the recorder 12 are driven, the signals a, b are transmitted to control the switching of the switches 10, 11. |
