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FM radio waves and radio stations

  1. Mar 28, 2013 #1
    Hi there. I have a (hopefully) quick question here.

    FM radio stations transmit their information by manipulating the frequency of radio waves, but each radio station is assigned to a specific frequency. If the frequency broadcasted by a radio station is constantly changing (to transmit info), how is it that you stay locked in to a single station?

    I hope that makes sense, and thanks!
  2. jcsd
  3. Mar 28, 2013 #2


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    To modulate the signal FM radio station only use a deviation of 75 kHz from center frequency.
  4. Mar 28, 2013 #3
  5. Mar 28, 2013 #4
    Each FM broadcast station is given a channel width of 200 kHz. As sas3 said the signal varies by up to 75 kHz from the center of the channel resulting in a occupied bandwidth of approximately 150 MHz with a guard band of 25 kHz on each side. Even with the guard band, stations on adjacent frequencies are spaced far apart geographically.
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