Build an Ultrasonic Proximity Detector - Detect objects through ultrasonic sound waves. __ Contact Jameco Electronics Cheap Ultrasonic Range Finder based on PIC16F877A with a 8MHz crystal - Everybody knows the speed of the sound in the dry air is around 340 m/s. Send a short ultrasonic pulse at 40 Khz in the air, and try to listen to the echo. Of course you won't hear anything, but with an ultrasonic sensor the back pulse can be detected. if you know the time of the forth & back travel of the ultrasonic wave, you know the distance, divide the distance by two and you know the range from the ultrasonic sensor to the first obstacle in front of it. __ Designed by Bruno Gavand
Dog Whistle - it's well known that many animals are particularly sensitive to high-frequency sounds that humans can't hear. Many commercial pest repellers based on this principle are available, most of them operating in the range of 30 to 50 kHz. __ Designed by Tomaz Lazar-Ljubljana, Slovenia
Introduction to acoustic thermometry - 04/21/11 EDN Technical Article: Use an ultrasonic transducer to measure air temperature in an olive jar. __ Circuit Design by Jim Williams, EDN's most revered contributor, passed away in June 2011 after a stroke. He was 63.
IR Detector/Emitter - This is a very basic infrared detector/emitter circuit. One major downside of this circuit, is that ambient infrared light will interfere with its detecting obstacles __ Designed by Andy Wilson
Medium Power 40Khz Ultrasound Transducer Driver - This crystal controlled circuit drives a 40KHz piezo transducer with a 30v peak to peak signal. . . Circuit by Dave Johnson P.E.-January, 2006
PIC16F873 Ultrasonic Range Meter - On these pages, I will introduce the Ultrasonic Range Meter with PIC 16F873. As for the range meter which doesn't use PIC , refer to "Ultrasonic Range Meter". I created the PCB pattern for this circuit using EAGLE CAD. With this circuit, the following features of PIC 16F873 are used. __ Designed by Seiichi Inoue
Receiver-Ultrasonic Switch - The circuit described generates (transmits) ultrasonic sound of frequency between 40 and 50 kHz. As with any other remote control system this cirucit comprises of a minI transmitter and a receiver circuit. Transmitter generates ultrasonic sound and the receiver senses ultrasonic sound from the transmitter and switches on a relay __ Designed by Andy Wilson |