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:
“Retirement requires the invention of a new hedonism, not a return to the hedonism of youth.”
—Mason Cooley (b. 1927)
“Justice is a moral virtue, merely because it has that tendency to the good of mankind, and indeed is nothing but an artificial invention to that purpose. The same may be said of allegiance, of the laws of nations, of modesty, and of good manners. All these are mere human contrivances for the interest of society.”
—David Hume (1711–1776)
“The rage for road building is beneficent for America, where vast distance is so main a consideration in our domestic politics and trade, inasmuch as the great political promise of the invention is to hold the Union staunch, whose days already seem numbered by the mere inconvenience of transporting representatives, judges and officers across such tedious distances of land and water.”
—Ralph Waldo Emerson (1803–1882)