Thread: Cellphones and Speakers

  1. #1
    Devil's Advocate SlyMaelstrom's Avatar
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    Cellphones and Speakers

    I don't know if anyone else has had this problem, but it's real common for me. Whenever my cellphone is accepting data, whether receiving a call or getting some update from the service provider, if it's near my TV or computer or anything else with speakers, the speakers start whining like crazy. I don't know if it's damaging the speakers or the phone, so if anyone knows about this like why it happens or if it's bad for anything, can anyone give me some input?
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    From a quick scan of Google, I would say that GSM mobile phones emit short pulses at 217Hz, which is around about where human speech occurs. At first this is a very low background emission, which non-shielded (i.e. most) speakers then pick up and amplify, hence the "dud dud dud-dud dud dud-dud dud dud" before a call starts/while pinging a network.

    This doesn't happen on CDMA (wacky American phones).

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    (?<!re)tired Mario F.'s Avatar
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    GSM capable cellphones are indeed the culprits. Well, GSM is. Not the cellphones. The frequencies get picked up very easily by most devices which aren't shielded. My Motorolla E1000 interferes with my laptop speakers and my CRT monitor when it's connected to the laptop. But doesn't interfere with my laptop LCD.
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    Registered User mrafcho001's Avatar
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    My phone only interferes with my CRT monitor, my headphones are not affected nor are my speakers, but then again i havent used my speakers since i got this cellular phone.
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    The superhaterodyne twomers's Avatar
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    I did a module of Telecommunications in University in first year, and my professor said that (and I don't know how), but the speakers and the very high frequencies from the phones somehow mingle, and a primitave form of AM radio receiver is made and the noises are due to that, it's got something to do with HPF and LPF I think. I don't think it's damaging though. You can also 'see' it, if you put your phone near a computer monitor, or a television screen, it should fluctuate when info is coming in, almost like the image doesn't want to stay in the screen ... damn, just read mrafcho001's post ... well, I'm not deleting what I wrote.

  6. #6
    Supermassive black hole cboard_member's Avatar
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    Mine seems to interfere with is my monitor (CRT). The image shakes and jumps about.
    Oh and my speakers sort of make a weird clicking sound.
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