A cordless phone has become one of the most common sights in homes. It provides ease of use with crystal clear sound quality. A cordless phone can be used while walking in the house or back yard, as it provides convenience of use.
Cordless phone works on the principle of radio waves. It sends and receives digital signals from base station to handset. This signal is then encrypted and converted into sound. Cordless phones are considered as a minor miracle of modern day life. Before the advent of mobile phone, a cordless phone was the only option that allowed people to talk while moving around freely in the privacy of their homes.
Most cordless phones have the same features as a standard phone and are available in many models. A cordless phone is simply a combination of a telephone with a radio transmitter and receiver. It consist of two main elements, handset and base unit. Main phone connection is attached to a phone jack and handset is kept on a slot provided on the base station for charging. Base unit receives incoming calls and converts it into an FM radio signal and transmits it to the handset.
This system of communication was first invented by a jazz musician named Teri Pall in 1965. Original system consistent of a base unit and a remote handset that worked at low radio frequencies. This low frequency permitted the use of handset from an area within range of the base. Power was required for the handset to function so in times of power failure, such a unit would not work. Frequency used initially for cordless phones was 1.7 Mhz. This was of inferior quality and had problems regarding range of accessibility and interference. FM was then used at higher frequencies of 49 MHz, 900 MHz, 2.4 GHz, and 5.8 GHz. This provided crystal clear sound quality and no interference by external objects.
Teri Pall made a breakthrough in the field of communications and is recognized as having revolutionized cordless communications.