basic antenna doubt

Discussion in 'Wireless & RF Design' started by pawankumar, Apr 9, 2011.

  1. pawankumar

    Thread Starter Active Member

    Oct 28, 2009
    hey friends,
    assume i am a kid and bear with me for this question.
    Consider a 555 timer circuit which acts as a short range A.M.Transmitter.Just connect a long (30cm) wire to the output pin and go wireless!!? :eek: How is this possible? I ve done a bitt of google work and seen a few videos.I could not understand many things which surround just one thing..

    How does current flow through an open circuit (as in the case of the above 555 circuit)?

    help me out friends..
  2. bertus


    Apr 5, 2008

    The NE555 will not be a great "transmitter", as it can only generate frequencies upto 2 Mhz, depending on the type and brand.

    Connecting a wire to the output will have the effect that the wire will "radiate" electromagnetic waves.

    Take a look in the links from this page for more info:

    A short wire will not "match" the frequency, as it is much to short.
    See this page for more info on antennas:

    The pages from the Neets, module 10, will have advanced info on both subjects:

  3. pawankumar

    Thread Starter Active Member

    Oct 28, 2009
    thanks bertus.....