ALEXANDER STEPANOVICH POPOV (sometimes spelled POPOFF; Russian : Алекса́ндр Степа́нович Попо́в; March 16 1859 – January 13 1906) was a Russian physicist who is acclaimed in his homeland and some eastern European countries as the inventor of radio .
Popov's work as a teacher at a Russian naval school led him to
explore high frequency electrical phenomena. On May 7, 1895 he
presented a paper on a wireless lightning detector he had built that
worked via using a coherer to detect radio noise from lightning
strikes. This day is celebrated in the
* 1 Early life
* 2 Popov\'s radio wave receiver
* 2.1 Operating principle * 2.2 Demonstrations
* 3 Later work * 4 Death and legacy * 5 Family * 6 See also * 7 Notes * 8 References * 9 External links
Born in the town
POPOV\'S RADIO WAVE RECEIVER
Drawing of Popov's radio wave based lightning detector
Along with his teaching duties at the naval school Popov pursued
related areas of research. Trying to solve a problem with the failure
in the electrical wire insulation on steel ships (which turned out to
be a problem with electrical resonance ) led him to further explore
oscillations of high frequency electrical currents. His interest in
this area of study (including the new field of "Hertzian" or radio
waves ) was intensified by his trip in 1893 to the Chicago World\'s
Columbian Exposition in the
Popov also read a 1894 article about British physicist Oliver Lodge
's experiments related to the discovery of radio waves by German
Circuit of Popov's lightning detector
In Popov's lightning detector the coherer (C) was connected to an antenna (A), and to a separate circuit with a relay (R) and battery (V) which operated an electric bell (B). The radio noise generated by a lightning strike turned on the coherer, the current from the battery was applied to the relay, closing its contacts, which applied current to the electromagnet (E) of the bell, pulling the arm over to ring the bell. Popov added an innovative automatic reset feature of a "self tapping" coherer where the bell arm would spring back and tap the coherer, restoring it to its receptive state. The two chokes (L) in the coherer's leads prevented the radio signal across the coherer from short circuiting by passing through the DC circuit. He connected his receiver to a wire antenna (A) suspended high in the air and to a ground (earth) (G). The antenna idea may have been based on a lightning rod and was an early use of a monopole wire aerial.
On 7 May 1895, Popov presented the paper "On the Relation of Metallic
Powders to Electric Oscillations", which described his lightning
detector, to the Russian Physical and Chemical Society in St.
Petersburg. Most Eastern sources regard Popov's lightning detector as
the first radio receiver, and the 7th of May has been celebrated
since 1945 in the
In 1895 Italian inventor
His paper on his experiments: "On the relation of metallic powders to electrical oscillations", was published 15 December 1895. He did not apply for a patent for his invention . In July 1895 he installed his receiver and a siphon recorder on the roof of the Institute of Forestry building in St. Petersburg. and was able to detect thunderstorms at a range of 50 km, however he was also aware of its communication potential. His paper, read at the 7 May 1895 meeting, concluded
I can express my hope that my apparatus will be applied for signaling at great distances by electric vibrations of high frequency, as soon as there will be invented a more powerful generator of such vibrations.
In 1896, the article depicting Popov's invention was reprinted in the 'Journal of the Russian Physical and Chemical Society'. In March 1896, he effected transmission of radio waves between different campus buildings in St. Petersburg. In November 1897, the French entrepreneur Eugene Ducretet made a transmitter and receiver based on wireless telegraphy in his own laboratory. According to Ducretet, he built his devices using Popov's lightning detector as a model. By 1898, Ducretet was manufacturing equipment of wireless telegraphy based on Popov's instructions. At the same time Popov effected ship-to-shore communication over a distance of 6 miles in 1898 and 30 miles in 1899.
In 1900 a radio station was established under Popov's instructions on
By the time the Apraksin was freed from the rocks by the icebreaker
Yermak at the end of April, 440 official telegraph messages had been
handled by the
DEATH AND LEGACY
In 1905 he became seriously ill and died of a brain hemorrhage on January 13, 1906.
ITU Telecom World 2011,
Igor Shchyogolev , Minister of Telecom and
Mass Communications of the
Some of his descendents escaped to Manchuria during the Bolshevik Revolution and eventually made their way to the United States. Among others the cousin, Dr. Paul Popov, who became a prominent physician in San Francisco and Paul's son, Egor Popov (1913-2001), who became a UC Berkeley Professor Emeritus of Civil and Environmental Engineering.
* ^ A B C D Smith-Rose, Reginald Leslie (2013). "Alexandr Popov".
Encyclopædia Britannica Online. Encyclopædia Britannica, Inc.
Retrieved 6 November 2013.
* ^ A B C D E F G H McKenna, Joe (2007). "Aleksandr Popov\'s
Contributions to Wireless Communication". IEEE Engineering Hall of
Fame. Institute of Electrical and Electronic Engineers website.
Archived from the original on 10 November 2013. Retrieved 6 November
2013. External link in publisher= (help )
* ^ A B C (author name redacted) (January 1960). "Did Alexandr
Popov invent radio?" (PDF). NSA Technical Journal. US: National
Security Agency. 5 (1): 35–41. Archived from the original (PDF) on
10 November 2013. Retrieved 6 November 2013. declassified 8 January
* ^ A B C D E F Huurdeman, Anton A. (2003). The Worldwide History
of Telecommunications. John Wiley and Sons. pp. 205–207. ISBN
0471205052 . A picture of Popov's receiver appears on p. 207, fig.
* ^ M. Radovsky, Alexander Popov Inventor of Radio, The Minerva
Group, Inc.- 2001, pages 37–38
* ^ A B C Christopher H. Sterling, Encyclopedia of Radio, Routledge
– 2003, page 1820
* ^ A B Sungook Hong, Wireless: From Marconi's Black-box to the
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