| 摘要 |
PURPOSE: To prevent a radio wave from being suddenly broken by sending a warning signal at the time of not detecting a radio signal and stopping sending the radio signal thereafter. CONSTITUTION: A control circuit 15 of a master set monitors the carrier of a speech channel during speaking; but when the carrier from a slave set is not detected by a tuner 12, the circuit 15 sends a warning command 1 to the slave set at intervals of, for example, 5 seconds to report the break of the carrier. This warning command is put on the radio wave of the speech channel and is sent and is received by the slave set. If detecting the break of the carrier continuously for one minute, the control circuit 15 of the master set sends a warning command 2 to the slave set to give notice that the speech channel will be disconnected and performs the disconnection processing of the speech channel (radio channel) and stops sending the radio wave and performs the disconnection processing of a speech path to a telephone exchange 3. |
