When we talk about mass communication, one of the device came in our mind is the Radio. Actually Radio was the first device which made mass communication possible. Information can be transferred miles of distance though Radio very easily. Here we will see how Radio was invented.
In 1885, Heinrich Hertz was the first to prove that electric waves could be transmitted and received wirelessly in the form of electromagnetic waves. Today it is recognized as the fundamental building block of radio and every frequency measurement is named after him(Hertz).
In 1893, Nikolai Tesla made first public demonstration of radio by transmitting electromagnetic waves in St. Louis, Missouri.
In 1896, Guglielmo Marconi Then he
In 1899, the R.F. Matthews was the first ship to request emergency assistance using a wireless apparatus (Marconi’s system).
In 1901, First trans-Atlantic signal sent-by Marconi from Ireland to Canada.
It was Reginald Fessenden who developed a way to combine sound and radio carrier waves. His first effort to transmit this mixed signal to a receiver removing the carrier wave so that the listener could hear the original sound got failed. However, in 1906, using Alexanderson’s Alternator, Fessenden made the first long range transmission of voice.
Lee DeForest is credited with the “father of American radio.” DeForest was a direct competitor to Marconi at the turn of the century (1899), when he was the chief scientist at the U.S.’s first radio firm ‘American Wireless Telephone
In 1906, Lee DeForest produces the “Audion,” a triode vacuum tube that allowed for amplification of radio signals.
Europe’s most famous broadcasting station, the British Broadcasting Company or BBC, began following in 1922. In fact, Marconi was one of the founding members along with other prominent leaders in the field of wireless manufacturers. Broadcasts began locally in London, but by 1925 it has spread to most of the United Kingdom. The station aired plays, classical music and variety programs. In 1927 the BBC became the British Broadcasting Corporation when it was granted it a Royal Charter. When the Second World War began all the television stations shut down and it fell on the shoulders of the radio to cover the war.
Edwin Armstrong—this WWI Army officer, Columbia University engineering professor, and creator of FM radio
invented the regenerative circuit, the first amplifying receiver and reliable continuous-wave transmitter; and the
superheterodyne circuit, a means of receiving, converting and amplifying weak, high-frequency electromagnetic