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Cell phone charging

  1. May 3, 2007 #1
    i read about a month ago that cell phone charging is about to be 'revolutionized.' Apparently, cell phones of the near future will have a wireless charging system where you plug a radio transmitter into the wall, and the cell phone recieves the signal and uses it to charge it's batteries.

    My question is, why can't you just take pre-existing radio freq/cell freq/etc freq signals out of the air and use them? Sure they're not very powerful signals but how many times have you been in a store when someone next to you makes a phone call. there's got to be some power there! no?
     
  2. jcsd
  3. May 3, 2007 #2

    russ_watters

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    Do you have a link? Sounds like an interference-causing waste of energy.

    Anyway, no, the amount of power in normal radio stations is pretty small.
     
  4. May 3, 2007 #3
  5. May 12, 2007 #4
    I cant see how this is possible, at least with RF.
     
  6. May 12, 2007 #5

    chroot

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    Sounds like hocus-pocus to me. And no, there's not a chance that you could use the energy used in RF communication to charge your batteries. There are so many problems with that idea that it's almost hard to begin listing them.

    - Warren
     
  7. May 12, 2007 #6
    I heard that some South Americans filled their back yard with a mass of bent wire from which they were able to extract from the atmosphere enough electricity, originating from RF broadcasts, to power their household appliances.

    I have no link to offer to support this, but feel free to Google.
     
  8. May 12, 2007 #7
    The south american thing sounds like a myth. The voltage present in the air due to RF is in the microvolts. To get any usable voltage from this, expecially to power appliances isn't possible.
     
  9. May 12, 2007 #8
    I did hear it was a very large space filled with a mountain of bent wire. If I remember correctly there was a powerful transmitter(s) located nearby.

    I will run a little search on this and post back if I find anything interesting.
     
  10. May 12, 2007 #9
    The only way I can think that something can charge "wirelessly" would be to inductively couple it, but that's nothing new... just maybe to cell phones. To use RF in a house would be quite dangerous, the power levels necessary to charge anything will give you an RF burn if you got too close to it, ie entered your house.
     
  11. May 12, 2007 #10
    If anyone is interested in the subject of wireless electrical energy transmission, then I suggest looking at the work of Tesla and more recently the HAARP project. Former HAARP scientist Dr. Nick Begich has produced a lot of material on this and related issues. He also has a weekday radio show.

    His website:

    Admin note: links to crackpot material are not permitted
     
    Last edited by a moderator: May 12, 2007
  12. May 12, 2007 #11

    Danger

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    Until I read the link, I assumed that it was a misinterpretation of an inductive coupling charger as used in electric toothbrushes, but apparently that's not the case. I don't know enough about RF to comment upon how much of it can be transmitted within close range, but it seems to me that it would be dangerous or maybe even illegal as regarding FCC regulations in the US and equivalent agencies in other countries.
    As a side note, isn't that the same magazine that reported on some sort of perpetual motion device in Ireland a few months ago?
     
  13. May 12, 2007 #12
    I guess you mean the steorn free energy project:

    Admin note: links to crackpot material are not permitted

    If Nick Begich has disscussed that particular project, then it is no somthing I have any memory of. I am not sure what magazine you mean? I have not heard Dr. Begich mention any magazine.

    The video presentation, linked to below on Google Video, was made by Nick Begich about 11-years ago. It is called Angels Don't Play This HAARP, and it is based on his book of the same title. It contains information on the HAARP project and some of the issues discussed in this thread, such as transmitting electrical energy by beaming it:

    Admin note: links to crackpot material are not permitted
     
    Last edited by a moderator: May 12, 2007
  14. May 12, 2007 #13

    chroot

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    Since this thread is unequivocally BS, I'm closing it.

    - Warren
     
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