Cordless telephones are telephones that have the capability of transmitting a signal over a short distance without the use of a cord. They differ from mobile phones, or cell phones, simply because they need a base station to connect to a landline. Cordless phones are one of the most popular types of landline connections on the market.
The purpose of a cordless phone is to provide a greater range of movement for those who feel they need it, but yet can still remain within a relatively limited geographical distance. Corded phones have a range as long as the cord, usually from six feet (2 meters) to 20 feet (6.5 meters). Cordless telephones have a range of 300 yards (300 meters) or more, depending on the type of connection, its power, and the obstructions present between the phone, often referred to as the handset, and the base station.
Cordless telephones generally operate at two main frequencies, one being 2.4 GHz and the other being 5.8 GHz. The 5.8 GHz is the new standard that many phones now advertise. In general, the higher the operating frequency, the more security the phone will have, making it harder for eavesdroppers to listen in on conversations through the use of scanners.
The first cordless telephones came onto the market in the late 1970s, though the technology took a few years to catch on and come down in price enough to the point that many consumers wanted to take advantage of them. The first phones ran at a frequency of 27 MHz. This provided a good range, but sound quality was low, leading to a lot of static and interference from other aerial signals.
This lower frequency had a number of problems associated with it. First, three-way calling was available between cordless telephones in relatively close range to one another. Second, those who wanted to could intercept the base station connected to a neighbor's line and make calls, even long-distance calls, using the other phone line. This led to a number of complaints and resulted in a few changes in the coming years which limited the range and changed the number of channels available.
Now, some say the evolution of cordless telephones is nearly complete. While it is not impossible to tap into a cordless phone conversation, it is much harder with digital technology. Cordless telephones are also to the point where many consider them to be on par with corded telephone quality sound. Still, testing the limits of the range will provide a decreased call quality.