PURPOSE: To connect automatically a subscriber line and a subscriber circuit by providing an incoming call detection circuit and a switch connecting a subscriber line and a subscriber circuit to a faulty subscriber supervisory when an incoming call is detected during fault supervising.
CONSTITUTION: A fault subscriber line monitor 5' is connected to a distributor 4 in a subscriber line 3 being an object of fault supervising. Thus, a contact 4a of the distributor 4 is opened at fault monitor to disconnect the subscriber line 3 and the subscriber circuit 2 and to connect the subscriber line 3 and the equipment 5'. In this state, a measuring circuit 5a supervises a fault of the subscriber line 3. When the subscriber line 3 and the monitor 5' are connected and a fault is being supervised, if an incoming call (ringer) comes from the subscriber circuit 2, the ringer enters an incoming detection circuit 5b, which detects an incoming call. In detecting the incoming call, the circuit 5b turns on a switch 5c. As a result the fault monitor is interrupted, the subscriber line 3 and the circuit 2 are connected to attain the talking with the subscriber terminal equipment 1.
HIKITA KOJI
KOMINAMI MITSURU
YAMAMOTO KUNIO
FUJITSU KYUSHU TSUSHIN SYST KK