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Destructive Interference & Cellular Phones Help!

  1. Jul 31, 2007 #1
    Hi All,

    I have a question about the practicability of this theory; now I'm no physicist, so please bear with me.

    A company sells a chip which is said to "harmonize" the effects of the harmful radiation from a cellular phone.*

    *I hope a debate won't ensue :devil:.

    Now, the chip is said to work like this:

    It emits a wave of the exact same wavelength, frequency, pulse, phase and amplitude of the "pathogenic" information wave; as that collides with the incoming wave, they literally cancel each other out (destructive interference)...

    ...However, would that not then make the functionality of the phone ineffective, in that it needs the information wave to translate the signal into audio?

    Is it possible that the information wave could undergo modulation instead, and how would that effect the signal?

    My other concern is, if the chip is emitting, in effect another information wave, then what's to stop that from being absorbed by the body?

    Sorry, it's fairly brief and non-descriptive, but if anyone is familiar with the technology I'd love to hear from you as I'm clueless.


  2. jcsd
  3. Jul 31, 2007 #2
    You are quite right. If the electromagnetic wave emitted by your phone is suppressed by interference, then of course your phone is not sending anything anywhere.

  4. Jul 31, 2007 #3


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    You can get the exact same harmonizing effect if you simply turn around in circles while you talk on your cell phone.

    Please videotape yourself performing this procedure and post it to the forum.
  5. Jul 31, 2007 #4

    Claude Bile

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    Colmodwyer; Your doubts are all well founded - the chip will actually double the amount of energy being emitted by the phone, effectively doing the exact opposite it claims to do, with the unfortunate side-effect of rendering your phone unable to send or receive a signal.

    I think we can throw this one into the crackpot basket. (My mind was made up as soon as I saw the word "harmonize".)

  6. Jul 31, 2007 #5


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    There's no justifiable reason to think cell phones are dangerous in the first place, especially not in reasonably sparing usage patterns. Save your money on crackpot nonsense, and spend your time worrying about choices that are known to directly impact your health -- like your diet and exercise habits.

    - Warren
  7. Jul 31, 2007 #6
    There has existed a small amount of evidence that mobile phones (like other sources of EM radiation) may be dangerous, but compared with the large amount of public concern for the topic, the total evidence just suggests that the risk must be low compared to other everyday risks (especially big ones like lack-of-exercise).

    As for the interference device.. it's theoretically possible but difficult in practice (similar to active noise cancellation), you're better off with a simple reflector (which should have the same effect, of cancelling the wave directed at your head, whilst doubling the wave directed out to the tower).
    Last edited: Jul 31, 2007
  8. Jul 31, 2007 #7


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    Will EM waves cancel each other out like compression waves in air?
  9. Jul 31, 2007 #8
    You've not seen Young's double slit interference pattern experiment?
  10. Jul 31, 2007 #9


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    Well, I at least have to move this thread out of the Quantum Physics forum (?). I'll plunk it in the EE forum for a couple comments about multipath and phased array antennas, and if anybody has any links to reputable cell phone RF exposure studies, I'll let those stand in the thread. Please remember, though, that a big part of HAM radio training has to do with RF safety. But we deal with 100s and 1000s of watts of transmit power. What do cell phones use for max xmit power? (I honestly don't know yet)
  11. Aug 1, 2007 #10


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    Cell phones use between 0.5 and 2 watts or so, depending upon the model and country and network.

    - Warren
  12. Aug 1, 2007 #11
    ==> http://vsg.quasihome.com/interfer.htm

    It appears to be some sort of online I game, and I think I won :biggrin:.

    I'm going to look into that, I'm sure I did such an experiment in high school.

    Thanks for all the replies.

    So what about modulation of a wave, presuambly that would still effect/change entirely the message?

    I'm not looking to buy this chip, but I need to be able to believe that this chip works, and that I would want to buy it, eventually...:rolleyes:

    The problem is, understanding how it works, or even believing that it works.

    Interestingly, I am being swayed by the arguments for more safety measures to be put in place when using cell phones; for every study that denounces the theory, there's another that supports it.

    And, of those that cannot find a link between cell phone use and cancer/tumors, most still suggest... "No, no, the phones are perfectly safe... But, I'd not let my children use them."(See the "Stewart Report")

    What swayed it for me however, was the story of Dr George Carlo, which, if you have an 1hr 40mins spare, you can listen to...

    ==> http://www.artsandopinion.com/2006_v5_n3/goldfarb-cellphone.htm

    Click the "listen here" link right after the article. Compelling to say the least... A cynic would say; "Well, he does have three books to sell."

    I'm waiting on an e-mail back from the inventors, I'll post their reply here as I'm sure some of you would be interested.

    Can we rule out the possibility of magic?

  13. Aug 1, 2007 #12


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    A recent study using subjects who claimed their health was affected by RF exposure, which found no correlation between the actual level of exposure and the reported symptoms:

    News report: http://www.newscientist.com/article/dn12348-no-evidence-for-cellphone-mast-illness.html
    Paper: http://www.ehponline.org/members/2007/10286/10286.pdf [Broken]
    Last edited by a moderator: May 3, 2017
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