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.
Using Passive Infrared Detection. Passive infrared sensors detect the proximity of humans and animals. These systems, popular in both indoor and outdoor security systems, work by detecting the change in infrared thermal heat patterns in front of a sensor. This sensor uses a pair of pyroelectric elements that react to changes in temperature.