| 摘要 |
PURPOSE:To detect easily the fault of a broadcast line and to simplify the constitution of a group-based general broadcasting device by dividing the broadcasting devices of the slave side into plural groups and performing the general broadcasting, the detection of the fault of the broadcast line, the monitoring of a loudspeaker device, etc. for each group of broadcasting devices. CONSTITUTION:A general broadcasting device includes a broadcasting device of the master side and plural broadcasting devices of the slave side. The control signal for start of general broadcast is supplied to a bidirectional branched amplifier 18 of a repeating device 30-1 via a control circuit 13. Then the control signal is applied to a transmitting circuit 32-1 for connection information of loudspeaker device coupled to a broadcasting device 31-1 of the slave side of corresponding plural divided broadcasting devices and to a repeating device 30-2 connected to the next broadcasting device of the slave side via a repeater 31-1. At the same time, a broadcast terminal 22 of the device 31-1 is connected to a broadcast circuit 12 via a broadcast signal amplifier 14 of the device 30-1. Then a connection switch 23 for the loudspeaker device is switched in response to the device 33-1. Then a folding fault of the circuit 12 is detected by a DC detecting circuit 16 of the repeater 30-1. In such a way, the constitution is simplified for a group-based general broadcasting device. |
