Early in the 19th century, Michael Faraday, an English physicist, demonstrated that an electrical current could produce a magnetic field.
In 1864, James Clerk Maxwell, a professor of experimental physics at Cambridge, proved mathematically that any electrical disturbance, that generates an electromagnetic field, could produce an effect at a considerable distance from the point at which it occurred and predicted that electromagnetic energy could travel outward from a source as waves moving at the speed of light.
In 1888 Heinrich Hertz demonstrated that Maxwell’s prediction was true for transmission over a short distance.
In 1901 the Italian physicist, Guglielmo Marconi, perfected a radio system that transmitted Morse code over the Atlantic Ocean.
In 1906 the American physicist Lee De Forest invented the vacuum tube which amplified radio signals that were received by antenna, thus much weaker signal could be transmitted over longer distance. The vacuum tube was also used to generate radio waves and soon become the main component of radio transmitter.
After World War II more advancements were made: The replacement of the vacuum tube by the transistor and of wires by printed circuits drastically reduced the power that radio equipment needed to operate enabling radio components miniaturization and more reliability.
During the years claims were made that as a matter of fact not Marconi invented radio but Oliver Lodge, Alexander (Aleksandr) Popov or Nikola Tesla , had sent wireless messages before Marconi got his patents (British 7777, US 763,772).
In 1943, in a celebrated 1943 Supreme Court decision, Marconi's 1904 US patent No. 763,772, was found to be invalid. As a result, some claim that this decision proves that Nikolai Tesla is the inventor of radio.
It does not really matter. What Marconi undoubtedly did invent was an entirely new science-based industry. In his hands an obscure and, to most people, unintelligible branch of physics became a consumer product like no other. We are used to being told that some new technology will change the world. Marconi's is one of the few that did.
For his scientific contribution Marconi was awarded the Nobel Prize in physics for the year 1909
In 1864, James Clerk Maxwell, a professor of experimental physics at Cambridge, proved mathematically that any electrical disturbance, that generates an electromagnetic field, could produce an effect at a considerable distance from the point at which it occurred and predicted that electromagnetic energy could travel outward from a source as waves moving at the speed of light.
In 1888 Heinrich Hertz demonstrated that Maxwell’s prediction was true for transmission over a short distance.
In 1901 the Italian physicist, Guglielmo Marconi, perfected a radio system that transmitted Morse code over the Atlantic Ocean.
In 1906 the American physicist Lee De Forest invented the vacuum tube which amplified radio signals that were received by antenna, thus much weaker signal could be transmitted over longer distance. The vacuum tube was also used to generate radio waves and soon become the main component of radio transmitter.
After World War II more advancements were made: The replacement of the vacuum tube by the transistor and of wires by printed circuits drastically reduced the power that radio equipment needed to operate enabling radio components miniaturization and more reliability.
During the years claims were made that as a matter of fact not Marconi invented radio but Oliver Lodge, Alexander (Aleksandr) Popov or Nikola Tesla , had sent wireless messages before Marconi got his patents (British 7777, US 763,772).
In 1943, in a celebrated 1943 Supreme Court decision, Marconi's 1904 US patent No. 763,772, was found to be invalid. As a result, some claim that this decision proves that Nikolai Tesla is the inventor of radio.
It does not really matter. What Marconi undoubtedly did invent was an entirely new science-based industry. In his hands an obscure and, to most people, unintelligible branch of physics became a consumer product like no other. We are used to being told that some new technology will change the world. Marconi's is one of the few that did.
For his scientific contribution Marconi was awarded the Nobel Prize in physics for the year 1909
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