Ultrasonic-pest-repeller


Posted on Apr 23, 2012

This circuit is a 555 timer IC connected as a square-wave generator. Its base frequency is approximately 45kHz, as detennined by the values of Rl, R2, and Cl. The 45-kHz carrier is frequency modulated by a modified trapizoidal voltage waveform applied to pin 5 of the 555 timer. That modulating voltage is developed by a network consisting of C2, R3, and R4 connected across one leg of the bridge rectifier. The sweep is approximately 20kHz on each side of the base frequency.


Ultrasonic-pest-repeller
Click here to download the full size of the above Circuit.

The speaker is a 2-inch piezoelectric tweeter.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

LCD Caller ID with AT89C2051
USB sound card with PCM2702
RF-powered sidetone oscillator
Antenna Low Power RF & Wireless Connectivity
ADIADM106610 a power monitors and sequencing control solution
15 kV @ 30 mA Floating-Output AC or DC High-Voltage Power Supply
FM Tracking Transmitter
Motorcycle Alarm No.1 - Construction Guide



Top