| 摘要 |
PURPOSE:To avoid the interference with another terminal station which uses a normal wave which has the same frequency as an urgency wave, by returning terminal stations, which use the urgency wave, to terminal stations, which use the normal wave, to broadcast a command from a control station with the normal wave. CONSTITUTION:When a control station 6, a repeating station 7, and a terminal block 1 constitute a normal wave circuit, the control station side makes a signal converting device 13 for urgency wave operatable after transmitting an urgency wave switching signal from a radio equipment 9 for normal wave. When receiving this urgency wave switching signal with the normal wave, the terminal station 1 switches a radio equipment 18 to the urgency wave. In case of broadcasting of a command, the control station side transmits broadcasting command information with the normal wave after transmitting an urgency wave switching release signal with the urgency wave. The terminal station 1 receives the urgency wave switching release signal to return the radio equipment to the normal wave and receives the broadcasting command. |
