Day 21 Arduino Advent Calendar
First published at Thursday, December 21 2017

Arduino Advent Calendar Day 21 - Ultrasonic Range Finder!
Today we're going to look at the Ultrasonic Range Finder.
With the Ultrasonic Range Finder, we can detect the presence of an object. The rangefinder works a bit like sonar in that an ultrasonic sound wave is sent out towards an object and the time it takes for the echo to return to the sensor is used to calculate the distance from the object.
Yup, enough talking about it let's go and build up the circuit over at guides.littlebird.com.au !
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