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FM reception

  1. Feb 12, 2005 #1
    How to improve FM radio reception? I have this boombox type radio in my room with one meter long telescopic antenna, reception is sometimes really bad. Should I just hook up lenght of wire to the antenna or what ?
    Thanks. :smile:
  2. jcsd
  3. Feb 12, 2005 #2

    well what i do normally....i have just a small antenna but i touch it to some very long metallic container in the open and it becomes clear..i would also love to know what is the processs to catch signals.. :blushing:
  4. Feb 12, 2005 #3
    If I recall FM transmission antennas are elliptically polarized, with a dominant horizontal mode. You might try angling the receiving antenna and adjusting its length.
  5. Feb 12, 2005 #4
    What is feasible to do is dependant on circumstance but one solution would be to purchase a good directional antenna and mount it as high as possible. An 8-element YAGI would go a long way towards improving reception in remote/fringe areas. [digression] Imagine a 5-element nearly 60-feet off the ground using guy wired bamboo for the pole…that one worked well.[/digression]
    FM is a peculiar beast however and sometimes the only thing that works well is to hold the antenna between finger and thumb, lol.
    Ok, you did mention ‘boom box’ and a great many of these are made to be flashy at the expense of a good receiver. If you’re a hand with circuits you can build a booster for the front end and that may very well all you’ll need. One easy way to determine this is to bring in a receiver that is known to have good reception and compare the two. If yours is lacking, I’d break out the soldering iron and spare parts box.
    Good luck.
  6. Feb 12, 2005 #5
    thanks guys for the sugestionss, I just attached 4 meters of wire to the antenna and so far no major problems with reception.
  7. Mar 5, 2005 #6


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    I enjoyed Boulderhead's suggestion of the 5-8 element Yagi, guyed 60 feet off the ground :biggrin:
    That would definately make an improvement.

    Something you could easily try and which ought to work better than a long random length of wire, is to make a 1/2[tex] \lambda [/tex] dipole, cut for the center frequency of the FM band (or if you had a particular station you liked, you could cut the dipole for that frequency). I have used a 1/2 [tex] \lambda [/tex] dipole for FM reception and suspend it horizontally and it works well.

    Here is an example of what I am talking about.

    Today most FM broadcast tranmissions are circularly polarlized, so if you are slightly more ambitious, you might build yourself a circularly polarized FM antenna.

    see this example of what i am referring to:
    http://www.n2.net/k6sti/attic.htm [Broken]

    (this antenna was made using 12 feet of #12 electrical wire and fed with 75[tex] \Omega [/tex] coax).
    Last edited by a moderator: May 1, 2017
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