• 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 and MIN 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 nefarious sort to make calls on your account.

Check out the next section to find out about cell-phone towers!

Cell-phone Towers
A cell-phone tower is typically a steel pole or lattice structure that rises hundreds of feet into the air. This cell-phone tower along I-85 near Greenville, SC, is typical in the United States:

This is a modern tower with three different cell-phone providers riding on the same structure. If you look at the base of the tower, you can see that each provider has its own equipment, and you can also see how little equipment is involved today (older towers often have small buildings at the base):

Here is the equipment owned by one of the providers:

The box houses the radio transmitters and receivers that let the tower communicate with the phones. The radios connect with the antennae on the tower through a set of thick cables:

If you look closely, you will see that the tower and all of the cables and equipment at the base of the tower are heavily grounded. For example, the plate in this shot with the green wires bolting onto it is a solid copper grounding plate:

One sure sign that multiple providers share this tower is the amazing five-way latch on the gate. Any one of five people can unlock this gate to get in!

Cell-phone towers come in all shapes and sizes, but I do believe this one in Morrisville, NC, is one of the weirdest looking!

That is one tall, ugly tree!

Check out the links on the next page and How Buying a Cell Phone Works for lots more information and consumer tips!

Just by their basic operation, cell phones have to emit a small amount of electromagnetic radiation. If you've read How Cell Phones Work, then you know that cell phones emit signals via radio waves, which are comprised of radio-frequency (RF) energy, a form of electromagnetic radiation.

There's a lot of talk in the news these days about whether or not cell phones emit enough radiation to cause adverse health effects. The concern is that cell phones are often placed close to or against the head during use, which puts the radiation in direct contact with the tissue in the head. There's evidence supporting both sides of the argument.

In this article, we will further explore this controversial issue. You'll find out how cell phones generate radiation and how they are tested for radiation levels.