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The Evolution of Telecommunications

by:TBT     2020-05-15
From Homer to Marconi Homer, speaking of the fall of Troy in the 11th Century BC, described a chain of beacons that were used to send the news back to Argos. This is one of the earliest examples of communication over a significant distance. The setting of the story of the Greece is significant because the word 'telecommunication' derives from the Greek word tele, meaning far or distant. As we will see, today the term 'telecommunication' is applied to both short- and long-distance communication by electronic means. The first invention that sought to bring about long-distance communication was the telegraph. The first models utilized 26 pairs of wires, one to transmit each letter of the alphabet. Samuel Morse saw the need to reduce the number of wires to one, which he achieved in 1838. To make his telegraph machine function on a single connection, he devised a coding system that produced an ECG-like line on tickertape. It was only later that one of his assistant produced the now familiar dots and dashes version of the code that could be sound read by the operators. By 1854 there were 23,000 miles of telegraph cable in use, with the first trans-Atlantic cable link established in 1868. When Alexander Graham Bell invented the telephone in 1876, not everyone was impressed. The Engineer-in-Chief of the British Post Office commented, 'My department is in possession of full knowledge of the details of the invention, and possible use of the telephone is limited.' The early telephony systems employed operators who would manually connect one customer's line to another. On discovering that the local operator was diverting calls to a business rival, a St. Louis undertaker, Amon Strowger, invented dial telephony. As with so many developments within the field of telecommunications, necessity proved to be the motor of invention. At the end of the 19th century, Marconi's invention of the radio telegraph was key to the development of future radio-based technologies. Using existing discoveries and inventions, he was able to build a working system that could initially transmit up to a distance of 2.4 kilometers. By 1899 he had refined his system so that British battleships could transmit up to a distance of 121 kilometers. From Marconi to Telstar At the turn of the century, Marconi sent the first radio signal across the Atlantic, despite the predictions of his contemporaries that this would fail due to the curvature of the Earth. They had failed to appreciate that the Earth's atmosphere could be used to reflect radio waves. Television made an appearance in 1926, when Baird produced his electromechanical machine. As is so often the case, a rival system proved to be just around the corner. Farnsworth demonstrated the superior electronic television 1927 that, thankfully, became the forerunner of today's televisions. Over the next few decades, a number of new technologies were developed that proved essential for the development for our modern telecommunications systems. In 1947, the transistor was invented, offering great reductions in the size of telecommunications equipment. The launch of the first telecommunications satellite in 1962 and the development of fiber-optic cable four years later accelerated the pace of development for high bandwidth telecommunications.
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