Now we do our conversions just like above. 121.779 / 5280 = .023 miles .94 / 60 / 60 = .000261 hours .023 / .000261 = 88.12 mph. So there you have it! How to calculate how fast you throw a baseball without a radar gun and only a stop watch.
IR Receiver and Remote. An IR receiver can detect bursts of infrared light sent by a common remote controller (like for a television), and then output a pattern of high/low signals to a Propeller I/O pin. This quick tutorial will first show you how to wire up the infrared receiver.
How does sonar work? Sonar is simply making use of an echo. When an animal or machine makes a noise, it sends sound waves into the environment around it. Those waves bounce off nearby objects, and some of them reflect back to the object that made the noise. It's those reflected sound waves that you hear when your voice echoes back to you from a canyon.