AM vs. FM

AM vs. FM Modulation

There are two types of radio broadcasting: AM and FM. The difference between them isn't how the radio works. That is the exact same in both FM and AM radios. (See How Radios Work) The difference is how the carrier wave is altered. AM radios use the amplitude or strength of the waves are varied to carry the sound information. With the FM radios, the frequency, the number of times that the current changes direction each second, of the carrier wave is altered. Most people use FM stations because both AM and FM are susceptible to slight changes in amplitude. When this happens in an AM radio, the listener hears static. With an FM signal, the changes don't alter the sound because the amplitude does not effect the frequency. The receiver of the FM waves just look over the changes in amplitude, so this results in no static at all.