FM waves. AM which stands for amplitude modulation, is a broadcasting method in which the carrier waves (carry the sounds of a program) are changed to match changes in the audio frequency waves. These are electric waves that represent the sounds of a radio broadcast. FM stands for frequency modulation and these waves, that go skyward, are not reflected. Instead, they pass through the atmosphere and go into space. AM signals, however, reflect off the atmosphere and travel back down to earth, causing broadcasts to be received at a much greater distance than FM signals. Since FM travels all the way to space and it does not bounce off the ground it does not create as much static as AM does. Radio waves, which travel at the speed of light, cannot be seen, heard, or felt in any way. When you listen to the radio, contrary to what some think, you are hearing the receivers pick up the waves and turn them into sound. Three more types of radio waves are; ground waves, ionospheric waves and tropospheric waves. Ground waves travel from the antenna along the surface of the earth.
Ionospheric waves, otherwise known as sky waves, are made up of radio waves that come from a transmitting antenna and go into the sky.
The ionosphere is the region of the rare field and ionized atmosphere around the earth, from 50 to
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