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How Cell Phones Work

By: Marshall Brain, Jeff Tyson & Julia Layton

Problems with Cell Phones

A cell phone, like any other electronic device, has its problems:

  • Generally, non-repairable internal corrosion of parts results if you get the phone wet or use wet hands to push the buttons. Consider a protective case. If the phone does get wet, be sure it is totally dry before you switch it on so you can try to avoid damaging internal parts.
  • Extreme heat in a car can damage the battery or the cell phone electronics. Extreme cold may cause a momentary loss of the screen display.
  • Analog cell phones suffer from a problem known as "cloning." A phone is "cloned" when someone steals its ID numbers and is able to make fraudulent calls on the owner's account.

Here is how cloning occurs: When your phone makes a call, it transmits the ESN (electronic serial number) and MIN (mobile identification number or phone number) to the network at the beginning of the call. The MIN/ESN pair is a unique tag for your phone -- this is how the phone company knows who to bill for the call. When your phone transmits its MIN/ESN pair, it is possible for nefarious sorts to listen (with a scanner) and capture the pair. With the right equipment, it is fairly easy to modify another phone so that it contains your MIN/ESN pair, which allows the crook to make calls on your account.

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For more information about cell phones and related topics, check out the links below and be sure to read How Buying a Cell phone Works for loads of helpful consumer tips.

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