Invention
James Clerk Maxwell showed mathematically that electromagnetic waves could propagate through free space. Heinrich Rudolf Hertz and many others demonstrated radio wave propagation on a laboratory scale.
Nikola Tesla experimentally demonstrated the transmission and radiation of radio frequency energy in 1892 and 1893 proposing that it might be used for the telecommunication of information. The Tesla method was described in New York in 1897. In 1897, Tesla applied for two key United States radio patents, US 645576, first radio system patent, and US 649621 . Tesla also used sensitive electromagnetic receivers, that were unlike the less responsive coherers later used by Marconi and other early experimenters. Shortly thereafter, he began to develop wireless remote control devices.
In 1895, Marconi built a wireless system capable of transmitting signals at long distances (1.5 mi./ 2.4 km). From Marconi's experiments, the phenomenon that transmission range is proportional to the square of antenna height is known as "Marconi's law". This formula represents a physical law that radio devices use.
Read more about this topic: History Of Radio
Famous quotes containing the word invention:
“A great man quotes bravely, and will not draw on his invention when his memory serves him with a word as good. What he quotes, he fills with his own voice and humour, and the whole cyclopedia of his table-talk is presently believed to be his own.”
—Ralph Waldo Emerson (1803–1882)
“Retirement requires the invention of a new hedonism, not a return to the hedonism of youth.”
—Mason Cooley (b. 1927)
“For this invention of yours will produce forgetfulness in the minds of those who learn it, by causing them to neglect their memory, inasmuch as, from their confidence in writing, they will recollect by the external aid of foreign symbols, and not by the internal use of their own faculties. Your discovery, therefore, is a medicine not for memory, but for recollection,—for recalling to, not for keeping in mind.”
—Plato (c. 427–347 B.C.)