Choosing the Right Cordless Phone

How To Choose the Right Cordless Phone   Consider range, security and features

There are several types of cordless phones available: Inexpensive, short-range models that have either 10, 25 or 40 channels

900MHz analog

900MHz digital

900MHz digital spread spectrum

2.4GHz digital 2.4GHz digital spread spectrum

Which phone is best for you depends largely on your immediate environment and your level of paranoia.

Cordless telephones are actually little radio transmitter/receivers. Your voice is transmitted via radio waves from the handset to the base, whereupon it’s transmitted via phone line to the person at the other end. When the other caller speaks, his or her voice is transmitted via radio from the base to the handset.

Although cordless phones have become the preferred type of telephone, the transmission method raises all manner of issues you must address before buying. Before you buy, consider:

1. What’s the phone’s range? How can I avoid interference?

2. How secure is my conversation?

3. What convenience features does the phone offer?

1. What’s the phone’s range? How can I avoid interference? Low-power radio signals can be blocked by walls or other physical barriers. The lowest-frequency (46-49MHz) cordless phones will have a range of only around 1000 feet, and usually much less than that, depending on how many physical obstructions there are (for instance, a floor between the first and second story or concrete, brick or steel-framed walls).

Analog 900MHz models have slightly longer range and are less affected by walls and such. Digital 900MHz phones provide a bit longer range. 2.4GHz DSS models employing digital spread spectrum (DSS) technology offer the longest range. Many DSS models are rated at more than half a mile, allowing you to carry your phone around your neighbourhood and not miss a call. Again, physical obstructions shorten the range.

Range can also be limited by interference from other local radio devices. When you buy a cordless phone, consider not only what and how many obstructions may be in your home that could limit the phone’s range, but also what other cordless or wireless devices you own and what the local traffic situation is.

Low-power, low-frequency radio waves of the type generated by all cordless phones (digital, digital spread spectrum or otherwise) are highly susceptible to local interference from other nearby devices that emit radio waves, including cordless phones, wireless speakers, microwave ovens, and even powerful local radio stations and CB broadcasts. The interference produced by some devices will be heard as intermittent static and will vary in intensity, depending on where you are in relation to the source. With sources such as wireless speakers, local radio stations and CB broadcasts (generated by trucks, taxi cabs, etc.), your phone may pick up the actual broadcast.

The least-expensive, lowest-power, lower-frequency phones will be most susceptible to this interference. Digital phones are less susceptible, and digital spread spectrum models are the least susceptible. Be aware, however, that some 900MHz phones can interfere with each other to the point of actually not being able to operate.

2. How secure is my conversation? A radio signal is transmitted each time you pick up a cordless phone and begin a conversation. This signal can be picked up by anyone with a common radio or police scanner, which can have a range of more than a mile. Eavesdropping is not limited by the range of your phone. This means that no matter how isolated you may feel, someone may be able to hear your conversation from some distance.

Most of these eavesdroppers are benign and merely curious (or just nosey). But anyone who listens to the news knows that there are some nasty people out there waiting to hear your credit card number. How do you protect yourself?

Although a digital phone will give you a clearer signal and a longer range, it is not secure. Some inexpensive cordless phones include "voice scrambling" technology. But voice scrambling is a halfway solution. Typically, these voice scrambling phones use a technology known as "voice inversion," which turns a conversation into gibberish. However, many scanners can defeat voice inversion with a simple add-on voice inversion decoder, leaving you right where you started but with an added sense of false security.

The only way to calm your paranoia and to be sure that no one but the intended party is listening in on your conversation is to buy a phone equipped with digital spread spectrum technology. And bear in mind that a "digital" phone is not necessarily a digital spread spectrum phone. If the box doesn’t say "digital spread spectrum," then it isn’t.

Digital spread spectrum technology was originally developed by the military. It has been battle-tested in inventory control operations where data wirelessly transmitted from the warehouse or retail floor to a backroom computer had to be secure.

No radio scanner in the world can decipher a digital spread spectrum signal. Your call would be heard as digital noise if someone happened across your call’s frequency. Odds are that someone using a scanner wouldn’t be able to zero in because digital spread spectrum employs frequency hopping technology. The signal is constantly changing frequency in an attempt to find the cleanest path to the base. Only your base, keyed to your specific digital spread spectrum handset, can pick up the signal. Of course, digital spread spectrum phones are more expensive, albeit not nearly as expensive as they were just six months ago. You may want to pay the extra dollars for the piece of mind that comes from knowing your call is totally secure.

3. What convenience features does the phone offer?

Whichever type of phone you shop for, remember that all the fancy features in the world (and they abound in this category) aren’t as important as the three basics: Ergonomics (If you tend to have long conversations, pick a unit that doesn’t feel heavy in your hand or clumsy next to your head.)

Usability, and Sound quality. Cordless phones share a plethora of corded models’ features, such as Caller ID, built-in digital answering machines, speed or memory dialing, hold and multi-line capabilities (conferencing, for example).

But the best convenience features unique to cordless phones are speakerphone, dual keypads and paging/intercom:

Speakerphone: A speakerphone in the base will allow you to answer a call without the handset, which is easily mislaid. Try to find a model with full-duplex speakerphone technology, which allows both calling parties to hear each other while speaking simultaneously or over the other. Half-duplex speakerphones allow only one person to speak at a time. Some phones offer speakerphones in the handset.

Dual keypads: A separate keypad on the base creates two phones for the price of one. You can originate calls from the base and engage in three — or even four-way conversations — someone on the base, someone on the handset, and one or two people at the other end.

Paging/intercom: The paging/intercom function allows you to call the base from the handset and vice versa. This feature could be handy if, for instance, you’re in the yard with the handset and you want to question someone who’s in the house by the base. The paging feature on the base is used to locate a misplaced handset by making it ring.

View a wide selection of 900MHz cordless phones, 2.4GHz cordless phones and 5.8GHz cordless phones at http://www.bestbuy.com/