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Why Your Clock Radio Is All Abuzz About iPhones

Posted by CmdrTaco on from the i-hate-that-sound-so-much dept.

blackbearnh wrote in with a story that's not really about the iPhone, but if your office speakerphones beep like mine does, read on: "If you own an iPhone, you may have noticed that it has a distinct and very annoying effect on clock radios, computer speakers, car radios, and just about anything else with a speaker. The folks at O'Reilly Media aren't immune, so they set out to discover just what is it about iPhones that makes them such bad RF citizens. The iPhones aren't the only bad apples in the cell phone basket and there's not much you can do about the problem. We're really in an interesting time in that there has never been so many high-powered personal transmitters just wandering loose in the world."

13 of 397 comments (clear)

  1. Nothing to see here. by HeavyD14 · · Score: 5, Insightful

    It just looks like someone has never had a GSM phone before.

    1. Re:Nothing to see here. by tripdizzle · · Score: 2, Insightful

      I have never known a cell phone not to have this issue. Perfect example of non-news.

      --
      "A claim for equality of material position can be met only by a government with totalitarian powers." Hayek
    2. Re:Nothing to see here. by JWSmythe · · Score: 3, Insightful

          I don't know how this ever made it to any news source. I'm trying to remember how long ago the first time I noticed it. It's been at least 10 years. My first phone that did it was an old Nextel.

         

      --
      Serious? Seriousness is well above my pay grade.
    3. Re:Nothing to see here. by lysergic.acid · · Score: 2, Insightful

      no, don't mod parent up, because he clearly didn't RTFA, which is quite informative and provides a lot of insight into this issue, actually:

      To be fair, the iPhone isn't the first phone that's been reported to have interference issues.
      [...]
      Rodman: We've seen it, well heard it really, quite a bit with GSM and TDMA phones. The source of this is the phone's transmitter, and what it's doing is sending its digital data broken up into very brief packets. Even when it's live, it's only transmitting about 10% of the time. But it's about 200 times a second. So what we're hearing is not so much the data itself, but the envelope, the shape of the packets as they turn on and off. And because we hear the higher frequencies much more clearly and they can interfere more easily than that basic frequency, while we wouldn't hear a 200 cycle tone, that's pretty low, when you interrupt something at that rate, it's kind of like putting a card into a bicycle wheel, you turn it from a gentle waving into a buzz, and it's the edges of that buzz we're so sensitive to.
      [...]
      Rodman believes that the iPhone may be getting singled out because it has such visibility in the marketplace right now.

      so TFA isn't picking on the iPhone here, and in fact the article even defends the iPhone, putting the blame of this phenomenon on other devices:

      At the end of the day, however, Rodman believes that the problem may lie, not in your iPhone dear Brutus, but in your clock radio.

      Rodman: There is confusion about what is responsible for this. Is it that there's one really bad model of cell phone out there that's causing the problems? Or is it that things are receiving it that shouldn't? I'm strongly of the believe that things are receiving it that shouldn't. Devices should be designed in a way that they're more resilient to stray transmitters that come along.

      TFA then goes on to explain that the reason we get these noises in so many electronic devices is because of "Part 15" of the FCC rules, which was put in place to produce cheap consumer electronics, with the trade-off being that consumers have to live with any interference that comes into their electronic devices.

      lastly, it should be pointed out that advanced smartphones like the iPhone put out much more of this noise than a regular cellphone (which usually does this only when a call is received) because of the smartphone's regular high bandwidth data transfers. so that is part of the reason the issue is being brought up in conjunction with the iPhone.

    4. Re:Nothing to see here. by mi · · Score: 2, Insightful

      everyone's CrackBerry going off

      Yep... I'm relying on the subtle noise, that my *berry makes on the computer-speakers as a mail-notifier... It is, actually kind-convenient — quiet enough not to wake-up the baby, but noticeable enough not to miss an e-mail.

      --
      In Soviet Washington the swamp drains you.
    5. Re:Nothing to see here. by OrangeTide · · Score: 3, Insightful

      Indeed. It is a well known phenomenon. I end up turning my blackberry off or leaving it in the kitchen on game/movie night because it makes all sorts of funny beeps on the surround system. I don't think people realize how powerful the transmitter in a cell phone is, and that it is not unique to iPhone.

      Apple customers tend to be rather picky and vocal about any possible defect with Jobs' perfect little products.

      --
      “Common sense is not so common.” — Voltaire
    6. Re:Nothing to see here. by Anonymous Coward · · Score: 1, Insightful

      If cellphone signals could take down an airplane, dont you think the terrorists would have figured that out by now?

  2. Re:GSM Buzz by nine-times · · Score: 3, Insightful

    Correct, lots of cell phones do this. If people are noticing it more with the iPhone, it's probably because people are more likely to want to hook the iPhone into audio equipment than with other cell phones.

  3. Re:the cause could be put into the summary by russotto · · Score: 5, Insightful

    Or, in other words, a 217Hz signal is amplitude modulated onto the GSM signal. Some electronic devices (like amplifiers) incidentally demodulate the 217 Hz and convert that to sound. 217Hz is well within the human audible range, thus... dutuh, dutuh, dutuh, dutuh, dutzzzzzzzz.....

    (since it's a 217 hz square wave you get lots of harmonics as well)

  4. Re:All GSM phones do that! by Moridineas · · Score: 2, Insightful

    You insinuated that the USA is technologically inferior becase we've been living without the GSM buzz? Huh... :p

    Verizon/Sprint/Alltell are the only big CDMA players left in the US afaik.

  5. Re:It seems to be AT&T more than anything... by flatulus · · Score: 4, Insightful

    Perhaps the AT&T cellsite is further away from your location than the T-Mobile cellsite. Hence, your phone has to "talk louder" for the AT&T cell to hear it.

    No cellular provider would intentionally instruct your cellphone to emit more power than required, because it would be self-defeating. Excess transmit power just means unnecessary interference to nearby cells on the same frequency. The cellular protocols provide a means for controlling the power of a handset up and down as needed to get "just the right amount" of RF energy at the cell tower's receiver.

  6. Re:really by jcuervo · · Score: 2, Insightful

    "SMS". Cute.

    --
    Assume I was drunk when I posted this.
  7. Re:Psh by vux984 · · Score: 2, Insightful

    Sorry buddy, parent poster is needlessly blunt but essentially right.

    There is nothing really wrong with them; they aren't really "crap". Its just that they aren't particularly special. Yet they are marketed (and usually priced) as if they were. The simple reality is that many other brands of speaker perform equally well at a considerably reduced price.

    To put it into slashdot terms, Bose speakers are like Dell's line of gaming PCs. Nothing wrong with them per se; they are certainly functional enough, but they aren't particularly special, and nobody who is serious about gaming and knows hardware is going to be remotely impressed. Meanwhile, compared to a custom rig ordered at newegg or ncix etc the Dell gaming unit cost more and does less.

    Like Bose.