This tutorial will guide you through the process of building a tachometer around an Arduino. Tachometers ... this version uses an Infrared beam to measure fan speed. As with last year’s PIC ...

An IR sensor determines how far the ping-pong ball is from the edge of the beam. With everything wired to the Arduino, you have a pretty good testbed for a controller. If is common to “tune” a ...

An IR sensor is located near the TV and wired to the receiver, which can be many feet away in the equipment rack. The receiver has an amplifier and an "IR blaster" that showers IR signals to all ...