For much of the 20th century radio was one of the most popular forms of entertainment. People used to sit on the floor of it and listen to programs, much as we watch television today. Indeed, when we think of radio we think of it as the box on which we hear our favorite music or talk shows.
Radio began in 1888 when German physicist Heinrich Hertz demonstrated the existence of radio waves (hertz is the unit we use today to measure the freuency of radio waves was in his honor). Radio waves also called electromagnetic waves, have the lowest frequency and the longest wavelength of any type of radiation in the electromagnetic spectrum. In a classroom experiment, Hertz made a condenser that produced these waves. Hertz didn't think his experiment had any practical applications, but another man did - Italian Guglielmo Marconi. Marconi thought electromagnetic waves could be used to transmit or send
signals. He was right. At first Marconi was able to transmit Morse Code only a couple of miles. But in 1901 he built a transmitter strong enough to send messages across the Atlantic Ocean. This was the beginning of wireless communication. It was even faster than the telegraph and best of all, no expensive wire or cable was needed. Radio became the way of sending Morse Code and Marconi created a very successful company that did just that. Messages were send by radio operators ashore from one ship to the other which include emergencies. Radio transmissions of Morse Code was certainly useful, even life saving, but others began wondering if it could be used to transmit other sounds, such as voice. On Christmas Eve, 1906, Reginald Fessenden proved that it could when he transmitted the first music and voice program. It originated in Massachusetts and was far away as Virginia. While many inventors thought of radio as a substitute for telegraph or telephone, which transmit information from one point to another point, the fact was that anyone with a receiver could listen on these "private" communications. Eventually the lack of privacy was turned into a benefit. Radio receivers was manufactured by the Westinghouse company to the public. They also decided to set up their own radio station. Westinghouse was granted the first United States broadcasting license for its station, KDKA, in October of 1920 and on 2 November 1920 KDKA held the first scheduled public broadcast. As more and more people began to listen in to radio broadcasts, inventors sought ways to design better recievers. Using new technology of electron tubes, engineers introduced more sensitive receiver technology , such as the regenerative superheterodyne circuits invented by American Edwin Armstrong. Fessenden also developed AM(amplitude modulation). AM was a better way to broadcast voice and and music. The main problem with AM was that the reciever often hears a lot of noise, like lightning and static interferences in the atmosphere. American inventor Edwin Armstrong came up with a different system - frequency modulation-or FM. By the 1930's Armstrong was able to improve the sound quality of radio transmissions by using FM. But AM was still king for many years before people could start listening in on FM broadcastings. By the year 1940, radio broadcasting was powerful, reaching its golden age. Programming was a lot like today's TV with news, sport, dramas, comedy shows, talk shows, soap operas, etc. Just as people today spend their evenings glued to televison, people gathered in their living rooms to listen to the radio. There were almost no portable radios, except in cars. After the 1947 invention of the transistor, however, radio shrank to the point where they could be truly taken everywhere. The transistor made it possible to combine AM and FM radios into a single, small package. Despite competition from television and the internet, radio remains a major source of information and entertainment with talk-show hosts having millions of listeners and for many people radio remains their primary source for music. Today internet or online radio is the popular format of radio.
Radio a History: From then till now