| 摘要 |
PURPOSE:To connect an incoming call from a telephone set at the outside of a premisese to a desired extension telephone set even if the operator is absent by requesting the transmission of a desired extension number signal to a caller at incoming and connecting automatically an external line to the extension with the extension number signal from the telephone set at the outside of premises. CONSTITUTION:When the operator is absent and the mode is brought into the automatic state while a key 7 is depressed, a control circuit 26 changes over a switch 3 through a contact 7' so as to connect an external line 11 to a line 13. Moreover, a master telephone set 8 becomes one of extension telephone sets. When an incoming call from a telephone set 1 at the outside of premises exists in this state, a 16Hz reception circuit 22 responds to it, a dial request circuit 23 is activated, the voice stored in advance, e.g., ''please dial the extension number.'' is transmitted to the telephone set 1. When a caller dials the extension number in response to this request, a dial pulse wave signal is transmitted from the telephone set 1, it is discriminated by a discriminating circuit 25 via the external line 11, the switch 3, the line 13, the 16Hz reception circuit 22 and a wave shaping circuit 24, and the connecting circuit 6 is connected to the extension telephone set corresponding to the dial pulse number. |
