| 摘要 |
PURPOSE:To enhance the safety and the stability by extracting at the reception side the specified frequency component of the FS modulation signal sent from the transmission side and then cutting off all operation command output when the level of the specified frequency component becomes lower than the fixed level continuously more than a fixed time. CONSTITUTION:The specified frequency component of the FS modulation signal transmitted from the transmission part is extracted by band pass filter 23, and the output is supplied to level comparator 24 to be compared with the fixed level. Comparator 24 features a fixed response time a little longer than the normal comparator, and thus main power source cut-off signal C is generated in the form of the output when the output level of filter 23 is kept under the fixed level more than the fixed time of comparator 24, power source 22, when receiving signal C, is cut off forcedly even though the main power source making switch of the transmission side is turned on. |
