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.


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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