Microphone

A microphone (or mike) is an electric auditory pickup device. It has a sensor that detects the vibrations (sound) in the air and converts them into an analog or digital signal. Microphones are used in numerous devices such as telephones, cellular phone, amateur radio, and two-way radios. A microphone is very similar to an audio speaker. Although microphones and speakers are designed for their specific purposes, the technology used is the same either way. By simply reversing the direction of power (cross-connect positive to negative and negative to positive) one device can technically be used for the opposite purpose.