| 摘要 |
PURPOSE:To prevent a transmitter receiver for a slave station from being disconnected from a line by outputting a signal for variation control over the origination and termination frequency of the slave station by a master station in response to the alarm signal from the slave station which indicates a drop in solar battery electric power, and controlling the origination and termination frequency by the slave station. CONSTITUTION:An electric power drop detecting circuit 108 outputs an electric power drop detection signal 82 corresponding to the extent of the electric power drop from a battery 110 to an alarm signal generating circuit 109. Then information on the electric power drop of the slave station is sent as a forward radio frequency signal 21 to the master station through a sent signal processing circuit 105 and a radio transmitting circuit 106. The master station sends control information, showing how much the origination and termination frequency of the slave station is controlled, as a downward ratio frequency signal 11 to the slave station. A slave station origination and termination frequency control circuit 107 recognizes how much the origination and termination frequency from the slave station control signal 62 is limited. A control signal 72 corresponding to that is outputted to an interface circuit 104, which variably limits origination and termination frequencies of respective terminals connected to the circuit 104. |
