| 摘要 |
PROBLEM TO BE SOLVED: To prevent a telephone nuisance caused by a portable telephone set or PHS by providing a weak radio oscillator suppressing the receiving sensitivity of the portable telephone set or PHS to prevent polling to disable the telephone set to communicate. SOLUTION: When a person enters an area prohibiting the use of a telephone set, a human body detector 2 operates and outputs a detection signal to a controller 10. The controller 10 automatically starts a receiver 7 and a sensitivity setting circuit 8 at the time of detecting a human body. The receiver 7 includes an automatic receiving frequency sweeping circuit receiving radio wave radiated during waiting the reception of the terminal telephone set or PHS. When the receiver 7 receives radio wave, the controller 10 stops the receiver 7 and the circuit 8. Then the oscillator 9 is automatically started to suppress the receiving sensitivity of the portable telephone set and PHS to prevent polling with a base station to disable communication. |
