PURPOSE: To obtain a wave detecting circuit whose cost is low, by applying the receiving signal to the resonance parallel circuit to extract resonant frequency components and by applying these components to the C-MOS inverter.
CONSTITUTION: The receiving signal is amplified through the front end circuit and the filter circuit by amplifier 5, and this amplified signal is input to detecting circuit through filter circuit 6 consisting of the parallel resonance circuit and so on and is detected, and the output circuit is driven by this detection output. In this detecting circuit 7, C-MOS inverter 11 connected to parallel resonance circuit 6a of filter circuit 6 through resistance R4 and detecting means 10 where the parallel circuit of resistance R3 and capacitor C3 is connected between the power source and the anode of backward diode D1 connected to the output of C-MOS inverter 11 are used.
KATAZUKI KUNIHARU
ISHIMOTO TAKAAKI
| JPS55165005A | 1980-12-23 |