Thursday, February 14, 2013

AM vs. FM

AM waves vs FM waves


FM Waves

FM stands for Frequency Modulation. This means that the frequency of the waves are varied. FM waves have higher frequencies than AM waves. For radios to catch these waves the antennas need to be higher because the waves are higher. These waves go in a straight line, so there can be some interference in them. These waves can also leave the Earth because they go in a straight line, and the Earth is round not square. FM radio has better quality. The stations, for example 93.7, are the frequencies. 93.7 means that there is an FM signal at a frequency of 93.7 MHz. Mega Hertz is millions of cycles per second.

AM Waves

AM stands for Amplitude Modulation which means that the amplitude, which is the highest or lowest point of the wave, is varied. The frequencies of these waves are much lower than FM waves. AM waves were discovered sooner than FM waves. This doesn't mean that the sound is greater, though, because it's not. AM waves are closer to the ground, unlike FM waves, so there are more interferences. AM radio doesn't have as great a quality as FM radio. AM radio goes by kilohertz. Kilohertz is thousands of cycles per second.

1 comment:

  1. What do you mean by FM waves go in a straight line? What happens to these waves when they leave the Earth? Do AM waves not leave the earth? This is all so interesting!

    I like the mention of what radio stations imply when it comes to frequency. 93.7 MHZ. Wow. Just think what the graph of that would look like.This world of waves would be so crazy to see, but millions of cycles in one second. Too bad we can't see.

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