| 摘要 |
PURPOSE:To confirm sequence operation and to prevent duplicated control by detecting the electric field strength of a radio wave at a specific time interval at a subordinate station in a radio alarm device and returning an end signal when the output is a specific level or below. CONSTITUTION:An electric field strength detecting receiver 116 detecting the electric field strength of the radio wave at a specific time interval is provided to a subordinate station 10 performing remote control from a master station by the radio wave, the radio wave is branched from an input terminal of the receiver 11 and inputted to the electric field strength detecting receiver 116. The electric field strength at the transmission frequency of the own station is sampled at a preset time interval from the arrival of a preparation end signal so as to detect the electric field strength of the same frequency. When the detected level is at the detected time zone and at a specific level or below, a data of logical value 1 is inputted to an AND gate 119. When the preparation end signal of the end signal and the condition of the detected level of the electric field strength are coincident, the end signal is returned to the master station via a transmitter 14. |
