this is a very simple alarm circuit is sure to have the police to beat a path to your door alarm circuit much - but the tracks advantage While entering the entrance, and I think I did before.
MW (medium wave) and sends the alarm circuit (small problem with the police at present) a. (Try 20 cm x 20 cm sheet of aluminum foil) with sensors IC1A only swing together 1 MHz This is modulated by audio frequency (tone) of 4093 CMOS IC1B generated. Hands and feet nears the sensor, the transmitter frequency (CMOS IC1A) significantly reduced.
It is now likely that the alarm circuit refer to 1 MHz radio, and also assume that you are tuned to the frequency of the rare. Was heard on radio for transmission of 1 MHz However, you can take your foot close to the sensors and hand, will reduce the frequency of the transmitter and heard on the radio beeps.
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