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RF frequency

  1. Jan 23, 2016 #1
    My question is about RF frequency..... The RFs are electromegnetics waves...That means they are one type of Light waves.... right??

    The other question is about perticular frequency of RF signals.....When we want to transmit or receive some perticular frequency..... we tune our radio at that perticular frequncy..... is that mean we set parameters of filter inside the radio???
  2. jcsd
  3. Jan 23, 2016 #2


    Staff: Mentor

    Yes, a photon is a photon. Different photons may have different frequencies, but they are all photons.

    That's overly simplified. You should study modulation/demodulation. You can start at https://en.wikipedia.org/wiki/Demodulation
  4. Jan 23, 2016 #3


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    This is a massive subject to deal with in one thread. Look at this wiki link, which discusses the basics behind RF receivers. The essence of an Radio Receiver is that it amplifies the band of frequencies (the carrier wave with its sidebands) that carry the wanted information by filtering and amplification and then it detects / demodulates the signal to 'extract the information' from the modulated carrier wave. The resulting signal is usually amplified further, before being fed to a loudspeaker (or the display circuits, if it's a TV signal).
  5. Jan 23, 2016 #4


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    There are numerous ways to access energy at specific frequencies, and they all involve filtering in some way. Generally an antenna converts EM waves to currents which are amplified and filtered, perhaps mixed to different frequencies.
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