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How Cordless Telephones Work

When You Shop

When buying a cordless telephone, there are several things you should keep in mind to avoid buying one that won't meet all your needs. Here are some of the most important things to think about:

Security, security, security!

Because your cordless phone is a radio transmitter, it broadcasts signals over the open airways rather than specifically between the base and handset. Therefore, it is possible for other people to listen to your phone conversation by using a radio scanner. Digital phones are better than analog phones in this area, but DSS offers the best protection against eavesdropping. Low-end 43-50 MHz and 900 MHz analog phones are not secure. In fact, most baby monitors can pick up phone conversations from 43-50 MHz cordless phones. 2.4 GHz analog phones are rare (most 2.4 GHz phones are digital), but offer some degree of protection because most commercially available radio scanners do not extend into this radio frequency.

If your cordless phone does not have DSS, then your conversation is about as private as the writing on the back of a postcard. Use care when divulging private information over a cordless phone.

Think about the type of battery in your cordless phone!

All cordless phone handsets have a rechargeable battery (nickel-cadmium, nickel-metal hydride, lithium). Nickel-cadmium batteries are subject to a memory effect, so it is best to let them drain entirely before recharging them on the base. Nickel-metal hydride and lithium batteries have no memory effect.