Tuesday, August 14, 2012

Insect Repellant

Repell those repugnent insects from your Garden this Summer with this insect repellant circuit. Designed by Graham Maynard the circuitry consists of a phase locked loop (CMOS 4047) wired as a 22KHz oscillator. The output is amplified by a pair of complimentary output transistors and drives a Motorola 3.25 inch Piezo. Current drain is around 120mA so an external power supply is recommended.
The piezo used was a standard 85mm square Motorola Horn, В Maplin part number В WF09K or WF55K. These are ratedВ +/-3dB to 28kHz.


Post a Comment

AC-DC-AC Converter for Wind Turbines under Unbalanced Voltage and Frequency Conditions Ch 1:-Introduction: 1.1   Wind Energy ...