This is the design circuit diagram of an ultrasonic mosquito repeller. The circuit is work with based on the theory that insects like mosquito can be repelled by using sound frequencies in the ultrasonic (above 20KHz) range. This is the figure of the circuit.
This circuit is operated using CMOS IC CD4047. The circuit is nothing but a PLL IC CMOS 4047 wired as an oscillator working at 22KHz. A complementary symmetry amplifier consisting of four transistor is used to amplify the sound. The piezo buzzer converts the output of amplifier to ultrasonic sound that can be heard by the insects. The circuit can be powered from 12V DC. The IC1 must be mounted on a holder. The buzzer can be any general purpose piezo buzzer.
This circuit is operated using CMOS IC CD4047. The circuit is nothing but a PLL IC CMOS 4047 wired as an oscillator working at 22KHz. A complementary symmetry amplifier consisting of four transistor is used to amplify the sound. The piezo buzzer converts the output of amplifier to ultrasonic sound that can be heard by the insects. The circuit can be powered from 12V DC. The IC1 must be mounted on a holder. The buzzer can be any general purpose piezo buzzer.
