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Satellite Dish for FM Radio?

  1. Jun 2, 2006 #1
    Is there any way that I could rig an FM radio antenna to a satellite dish and pull in FM stations that are one or two hundred miles away?
     
  2. jcsd
  3. Jun 2, 2006 #2

    Danger

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    Only if the broadcast is coming from a satellite. FM is pretty much line-of-sight. It doesn't bounce off of the ionosphere like many other radio signals.
     
  4. Jun 2, 2006 #3
    It wouldn't improve my reception?
     
  5. Jun 2, 2006 #4

    Danger

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    It might even hinder it. Different types of EM radiation require antennae that are specifically designed for them. Having a dish connected to your FM antenna might just throw it out of adjustment.
     
  6. Jun 2, 2006 #5
    The higher the frequency the less it tends to bend around the horizon. Also, the higher the frequency the less it tends to be reflected back to earth by the ionosphere. It isn't the fact that it is frequency modulated, it is the fact that it is around 100 Mhz. If I recall correctly, FM broadcast is horizontally polarized and transmitted with as low of a radiation angle as possible. In other words, the antenna is designed to concentrate the radiation straight out away from the antenna with as little going up into the sky as possible. Rare propagation conditions can yield pulling in an FM station from several hundred miles away. I wouldn't waste my time with a satellite dish. It's not going to throw anything out of adjustment permanently, but it is the equivalent of dragging 500 pounds of cement blocks around on a rope tied to the bumper of your car to improve the 0 to 60 time.
     
  7. Jun 2, 2006 #6

    dav2008

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    So would you be able to pick up AM with a satellite dish?
     
  8. Jun 3, 2006 #7
    My computer is on a 2.4GHz wireless network and has an external dipole antenna. I have a simple parabolic reflector behind my antenna. I made it out of a Coke can, and it boosts my signal 8-10 dB.

    I would think that I could do the same thing with an FM antenna. I could probably make the reflector a lot better too (assuming I can't buy one).
     
  9. Jun 3, 2006 #8

    Danger

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    You still can't overlook the fact that the transmission tower has to be above the horizon. It doesn't matter what kind of antenna you have if there's no signal for it to pick up.
     
  10. Jun 3, 2006 #9
    I did the calculations. For an antenna that is 244 meters above sea level the line of sight is 35 miles :grumpy: . I suppose spherical wavefronts and gravity might extend that a little bit, but I don't expect it to be much. Looks like I might have try an AM dish or something like that.
     
  11. Jun 3, 2006 #10

    Danger

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    Gravity of the Earth-type doesn't affect EM to any measureable degree. You need something on the order of a solar mass for that. You can extend your range by putting your normal FM antenna on top of a tower, but it might not be worth your while (and there are zoning bylaw issues). If you have satellite reception already, might I suggest that you save yourself a pile of hassle and just subscribe to satellite radio?
     
  12. Jun 4, 2006 #11

    NoTime

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    A high gain yagi antenna cut for FM can pull in a station 100 miles away with decent signal strength, providing there isn't a mountain in the way.
    200 miles might be a push.
    Used to get both Boston and NY FM and TV stations that way.
     
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