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Powerless radio

  1. Sep 16, 2009 #1
    Hi

    Just have a quick question, for audio input (AUX) into speakers would it be possible to make a powerless radio receiver plug in, or would it require power?

    Thanks
     
  2. jcsd
  3. Sep 16, 2009 #2

    chroot

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    Well, a crystal radio is unpowered, but I doubt you'd be happy with the results. And it'll only work for AM.

    - Warren
     
  4. Sep 16, 2009 #3

    jambaugh

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    If you want a quick answer you need to give more detail. By "powerless radio" do you mean e.g. a crystal radio?

    If so then yes its possible but you'd need to match impedances with an audio transformer and I wouldn't bet on you getting a very good quality signal.

    Are you talking about a regular radio but with say no batteries? If so then No! The whole receiver circuit needs power before you even get to the audio amplification stage.
     
  5. Sep 16, 2009 #4

    vk6kro

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    Sounds like you mean the powered speakers that are used on computers.
    These have an AUX (line out from computer sound card) connection, but there is no DC power available there.
    A radio would require DC power, but you could borrow power from the speaker power input.

    These seem to always have an external DC power source from a wall wart or similar. You could get DC power from there if you get advice first on how to do it.


    You keep asking basically the same question. Why not just say what you want to do?

    AUX In/Out Power?
    Hi

    Sorry i was just wondering how if any how much power is provider by aux in and out audio ports?

    Thanks

    Power from headphone socket?
    Hi
    I was wondering if there is power from the headphone socket on appliances? if so how much? also is there power from a line in 3.5mm port? again how much?

    Thanks for your help

    Now this one:
    Hi

    Just have a quick question, for audio input (AUX) into speakers would it be possible to make a powerless radio receiver plug in, or would it require power?

    Thanks
     
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