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Audio to infrared converter

  1. Jun 20, 2008 #1
    Although it "sounds" weird... it is possible:
    http://www.freepatentsonline.com/6931231.html

    Application:

    http://jumpjack.wordpress.com/2008/06/10/turn-your-phone-into-an-universal-remote-control/


    You can convert an audio file into an infrared signal which can control your TV set!

    But I've a couple of questions, don't know if this is the best place to ask them:
    - why can a phone with "symetrical audio output" (???) reproduce a 38000 HZ signal, knowing that any audio device can usually reproduce only up to 20000?
    - is it possibile to reproduce a 38000 Hz signal using a MONO audio output rather than a stereo one?
    I did some studies, and the result is "yes"... but when I do it, I don't ger results I waited!
    http://www.planetmobile.it/jumpjack/ir2audio.xls" [Broken]
    http://www.planetmobile.it/jumpjack/immagini/ledrem.JPG" [Broken]

    I think that the opposite parts of the audio wave get "summed up" when they're converted into light, thus doubling the output frequency. But actually I see only ONE led transimitting light. Why?!?
     
    Last edited by a moderator: May 3, 2017
  2. jcsd
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