Test mode :Using IO trigger for high level signal.( Not less that 10us),The Module sends eight 40 kHz automatically and detect whether there is a pulse signal back. The detection zone: 0.78~196 in/ (2cm~500cm); High precision: up to 0.12 in/(0.3 cm) Effectual angle: less than 15° Power supply: 5V DC; Quiescent current: less than 2mA. Test distance = ((Duration of high level)*(Sonic :340m/s))/2 Package included: 8pcs HC-SR04+ 4pcs Mounting Bracket(support HC-SR04 only) HC-SR04 Ultrasonic Sensor is a device that can measure the distance to an object by using sound waves. It measures distance by sending out a sound wave at a specific frequency and listening for that sound wave to bounce back. By recording the elapsed time between the sound wave being generated and the sound wave bouncing back.
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