Chapter 6. Potentiometer Sensors

A potentiometer, or pot for short, doesn't change in resistance with temperature like a thermistor, or light level like a CdS light-dependent resistor. It changes with the rotation of a mechanical shaft. You're probably already familiar with the device because it's commonly used as the volume control on audio equipment. Rotating the shaft changes the resistance between the center and outer two terminals. It's a kind of self-contained voltage divider. Usually the shaft can rotate only 270 degrees, but multiturn versions are available. Figure 6-1 shows several examples of potentiometers.

Examples of potentiometers

Figure 6-1. Examples of potentiometers ...

Get Extreme NXT: Extending the LEGO MINDSTORMS NXT to the Next Level, Second Edition now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.