The invention of the telegraph, in the 1830's, showed how messages could be transmitted using electrical signals. But in order to send and receive messages between two places it was necessary that they were linked by wires.
                                  In 1864, the englishman, James Clerk Maxwell, predicted that messages could be sent by electrical signals even without wires. He was proved right in 1887, when Heinrich Hertz, a German physicist, succeeded in sending a signal over a very short distance without the use of wires.
                                 The first practical use of wireless transmission was, by a strange coincidence, demonstrated by two young inventors working different continents at about the same time.
                                  In Calcutta, in 1895, Jagadish Chandra Bose, using an improved version of Hertz's apparatus, transmitted a signal through a solid wall without the aid of wires, making it ring a bell and explode a mini mine. Guglielmo Marconi, a 20-year-old Italian, conducted a similar experiment in which he sent an electrical signal without wires and rang a bell at the other end of the room.
                                 And so, the foundation of modern broadcasting was firmly laid.
                                 Before long, in 1915, the human voice was broadcast for the first time across the Atlantic ocean. A message sent from Virginia, USA, was received by a French military radio station atop the Eiffel Tower in Paris. And sometime later the radio was designed.!

Radios Today


Post a Comment