File:Marconi parabolic antenna 1922.jpg
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![File:Marconi parabolic antenna 1922.jpg](https://upload.wikimedia.org/wikipedia/commons/thumb/1/1b/Marconi_parabolic_antenna_1922.jpg/763px-Marconi_parabolic_antenna_1922.jpg?20160721104123)
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Parabolic antenna made by Marconi
Summary
[edit]DescriptionMarconi parabolic antenna 1922.jpg |
English: An experimental parabolic antenna used by radio pioneer Guglielmo Marconi in investigations of directional radio transmission 1917-1922, It consists of a dipole antenna at the focus of a parabolic reflector made of metal rods 1.5 wavelengths long. The reflector directs the radio waves from the dipole into a beam. The source said the wavelengths used in these experiments were 2 and 3 meters (150 and 100 MHz), although at these wavelengths the antenna should be somewhat bigger. With a special spark gap transmitter C. S. Franklin, Marconi's chief scientist, transmitted a distance of 20 miles. |
Date | |
Source | Retrieved July 16, 2016 from Guglielmo Marconi, "Radio Telegraphy" in Radio Broadcast magazine, Doubleday & Co., New York, Vol. 1, No. 4, August 1922, p. 345 on http://www.americanradiohistory.com |
Author | Guglielmo Marconi |
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[edit]Public domainPublic domainfalsefalse |
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current | 10:41, 21 July 2016 | ![]() | 845 × 664 (134 KB) | Chetvorno (talk | contribs) | User created page with UploadWizard |
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