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Why Unlocked Phones Don't Work In the US

Posted by timothy on from the they're-just-not-trying-hard-enough dept.

schnell writes "Unlocked cellular devices have long been a part of the wireless landscape in Europe and elsewhere. But longtime industry analyst Andrew Seybold explains why that model doesn't work in the US due to technology and frequency differences, and why LTE adoption may not make things any better."

5 of 442 comments (clear)

  1. Yeah right. by Anonymous Coward · · Score: 5, Insightful

    Technology and frequency differences? You've got to be shitting me. They don't work because the cell operators are greedy assholes.

    1. Re:Yeah right. by ScrewMaster · · Score: 5, Insightful

      Technology and frequency differences? You've got to be shitting me. They don't work because the cell operators are greedy assholes.

      It would be interesting if the cell phone manufacturers offered a swappable, standardized radio module that would pop in and out like the battery. That way you could buy an expensive smartphone, and leverage that investment by just picking up a new radio module to move to a new network. Of course, the reality is that these pricks can't even agree on a particular power plug, so I wouldn't hold your breath and besides, they're perfectly happy if you are forced to buy a brand-new phone just to go to a different wireless provider.

      --
      The higher the technology, the sharper that two-edged sword.
    2. Re:Yeah right. by MoonBuggy · · Score: 5, Informative

      I know it's against Slashdot tradition, but I'd recommend that you RTFA. The summary gave me the same impression - that it would be some corporate fluff piece about how it's a good thing that the networks are screwing you - but the article itself is actually a very well reasoned technical explanation of the various bits of spectrum (and the the protocols running on them) in use today and in the near future, and how these often interfere with interoperability.

    3. Re:Yeah right. by tlhIngan · · Score: 5, Informative

      Unfortunately, a standardized plug does diddly if you don't standardize how to charge.

      There are a few billion ways you can charge from USB. There's the good old dumb "assume 500mA" method - where you assume you can draw 500mA from USB. Works fine for PCs and their chargers, but not so much if your USB host is power-limited.

      Then there's the USB charging spec - where the charger shorts D+ and D- lines, and the device assumes it can draw the appropriate amount of current as the charger it comes with - 500mA, 800mA, 1A, 2A. Again, no standard on how to pick the current, so a device is free to draw as much as possible.

      There's the Apple method, where resistors on D+ and D- lines tell the device how much power the charger can provide to prevent drawing too much power (iPods start at 100mA until enumerated at 500mA or more, or connected to a charger where it can select 500mA, 1A or 2A).

      There's also using the ID line with resistors that identify the device - an ADC converts the voltage to identify the accessory (charger, car kit, high-current charger, etc).

      There's also the USB high power spec, but that's for USB hosts that can provide more power.

      Even worse, I've seen some devices destroy the charger because they assume the manufacturer's charger and draw more current than the charger can provide.

      Fun fun fun.

      Anyhow, at least for iPhone users, you can buy iPhones in Canada which are fully unlocked from Apple stores in Canada. I've seen a number of US people come to Canada to buy unlocked iPhones.

  2. Re:Every Network Is Different by LurkerXXX · · Score: 5, Insightful

    Yeah, breaking up Ma Bell was a terrible idea. I just loved having to pay rent on every phone in my house every month, because you weren't allowed to own your own phone.

    You know nothing.