A cordless phone is a model of telephone which replaces the coiled wire between the handset and base unit with wireless radio technology. The land line connection from the phone company is still fed into the base unit, but the powered handset transmits and receives radio signals in place of traditional electronic pulses. As long as the base unit's antenna can receive transmissions from the handset, the user is free to roam a few hundred feet without being tethered to a coiled wire.
A cordless phone is not the same as a wireless phone, however. The handset must be returned periodically to the base unit for recharging, and the base unit must be physically connected to both a telephone line and an electrical outlet. Many of these phones are rendered inoperable during a power outage, unless owners purchase a battery-powered backup device specifically designed to restore temporary service.
In the earliest days of telephones, recreational usage was not a priority. Users spoke directly into a hardwired box and used a corded earpiece to hear responses. As telephone technology improved and home phone usage increased, telephone models became more streamlined and stylish. But the restriction of hard wiring often made intimate conversations difficult. The only workable solution seemed to be making the wire connections longer for greater mobility. Thus, the era of long, coiled handsets and lengthy connection wires was born.
With the advent of wireless radio technology in the 1970s and 1980s, several telephone manufacturers created a high tech alternative to handset cords. The first cordless phones used the same two-way radio technology as walkie-talkies or baby monitors. The FCC allotted a bandwidth just beyond the AM radio frequencies for cordless telephone transmissions. An early version featured long extendable antennas in place of a hardwired handset cord. The quality of conversation was extremely variable, however, and a cordless phone was often plagued by electronic interference and poor reception.
A modern cordless phone system uses a stronger transmission signal (from 900 megahertz to 2.4 gigahertz on average) and an improved antenna/receiver system to provide exceptionally clear communications. Rechargeable batteries in the handset provide hours of available talk time, although almost any cordless phone can lose power without warning. Separate channels within the assigned bandwidth improve the clarity and add extra security through electronic scrambling or detuning. Earlier technology could not prevent illicit eavesdropping through scanners set for the same frequency as wireless baby monitors. Modern systems are much harder to hack electronically, although users may still want to use other communication methods when discussing highly sensitive information such as social security numbers or personal identification codes.