Ultrasonic Beam Barrier Circuit
by D Mohankumar in Alarms |
This circuit generates inaudible ultrasound to make a barrier across the entry. At the moment the circuit detects a break in the sound barrier, it generates a loud alarm indicating the entry of a person. This can be used to protects the entry passages and helps to detect unauthorized entry of persons in protected areas. The...
Electronic Dog Repellent Circuit
by P. Marian in 555 | DIY |
The electronic dog repeller circuit produces a discomforting but not harmful, high frequency sound, audible to dogs but not to humans. Help stop the approach of unwanted dogs at up to 15 feet. It uses 555 circuit at is easy to build, this is a dog chaser schematic that you can do it yourself. From R3 adjust the resonance...
Ultrasonic Sensor Circuit
by P. Marian in Measure |
This Ultrasonic Sensor Circuit consists of a set of ultrasonic receiver and transmitter which operate at the same frequency. When something moves in the area covered the circuit’s fine balance is disturbed and the alarm is triggered. The ultrasonic circuit is very sensitive and can be adjusted to reset itself automatically or...
Electronic Siren with Multitone
by P. Marian in Audio |
This multitone electronic siren is useful for burglar alarms, reverse horns, etc. It produces five different audio tones and is much more earcatching than a single-tone siren. The circuit is built around popular CMOS oscillator-cum-divider IC 4060 and small audio amplifier LM386. IC 4060 is used as the multitone generator. A...
Electronic Pest Repellent Circuit
by P. Marian in Audio |
There are many ultrasonic pest repellent devices available on the market but a major drawback is that their power output is low and their effectiveness suffers. This electronic pest repellent generates powerful ultrasonic signals to repel pests. In addition to the ultrasonic frequency oscillator built with the CD4047 IC,...
Dog Repellent Project Circuit
by P. Marian in 555 | Audio | DIY |
The electronic dog repellent circuit diagram below is a high output ultrasonic transmitter which is primarily intended to act as a dog and cat repeller, which can be used individuals to act as a deterrent against some animals. It should NOT be relied upon as a defence against aggressive dogs but it may help distract them or...