| 摘要 |
<p>PROBLEM TO BE SOLVED: To detect a concealed microphone from display results of search without requiring constant monitoring of receiving state by searching an electromagnetic wave of preset frequency and storing an electromagnetic wave containing a voice band signal in a voice file upon receiving along with time information. SOLUTION: A searcher sets a receiver 1 in an objective area to be searched where a microphone is concealed possibly and arranges a controller 2 such that it causes no hindrance of daily action in the objective area to be searched. The receiver 1 and the controller 2 are connected through a voice signal line 3 and a communication signal line 4 and then power is turned on. Subsequently, the working frequency, demodulation system, recording time, measurement start/end time of the object to be searched, i.e., the concealed microphone, are inputted, along with a reference receiving level for determining presence of a voice band signal, by an operating means 24 according to a display on the display means 23 in the controller 2. More specifically, working frequencies of the concealed microphone are searched and set and then electromagnetic wave generated from the concealed microphone is received while scanning electromagnetic wave of set frequencies sequentially.</p> |
