| 摘要 |
PURPOSE:To change over a main telephone set from a remote distance in a station in which an attendant board is not installed or a station in which a person for a maintenance is not present or the like by disposing a number receiving circuit capable of receiving a dial information in a main telephone switching unit. CONSTITUTION:When a calling subscriber 10 of A station carries out an outgoing dial to B station, the B station receives the dial information by an incoming register 20 and transmits to a central control unit 13. In the control unit 13, when it is judged that the dial information is a main telephone set switching information, a link 2 is closed, and a service set sound is transmitted for a fixed time to a calling subscriber 10 by a service sound transmitting trunk 21. Then, when the calling subscriber 10 dials a password number, a coincidence is compared by a number receiving circuit 19, if the number coincides, a main telephone set switching device 17 is activated, and the switching to the main telephone set is performed by a main telephone set switching circuit 18. |
