Alexander Stepanovich Popov
|Alexander Stepanovich Popov|
16 March 1859|
Turyinskiye Rudniki settlement of Perm Governorate (currently Krasnoturyinsk of Sverdlovsk Oblast)
|Died||13 January 1906
St. Peterburg, Russian Empire
|Notable awards||Order of St. Anna of 3rd and 2nd grades
Order of Saint Stanislaus (Imperial House of Romanov) of 2nd grade
Silver medal of Alexander III reign honour on the belt of Order of Alexander Nevsky
Prize of Imperial Russian Technical Society
Alexander Stepanovich Popov sometimes spelled Popoff (Russian: Алекса́ндр Степа́нович Попо́в; March 16 [O.S. March 4] 1859 – January 13 [O.S. December 31, 1905] 1906) was a Russian physicist who along with Guglielmo Marconi was the first to communicate messages by radio waves.
In 1894 he built one of the first radio receivers, using a coherer. Further refined as a lightning detector, it was presented to the Russian Physical-Chemical Society on May 7, 1895—the day has been celebrated in the Russian Federation as Radio Day. The paper on his findings was published the same year. On March 24, 1896, he demonstrated transmission of radio waves between different campus buildings in St Petersburg. He was also the first to use a wire aerial.
Born in the town Krasnoturinsk, Sverdlovsk Oblast in the Urals as the son of a priest, he became interested in natural sciences when he was a child. His father wanted Alexander to join the priesthood and sent him to the Seminary School at Yekaterinburg. There he developed an interest in science and mathematics and instead of going on to Theology School in 1877 he enrolled at St. Petersburg university where he studied physics. After graduation with honors in 1882 he stayed on as a laboratory assistant at the university. However the salary at the university was inadequate to support his family, and in 1883 he took a post as teacher and head of laboratory at the Russian Navy's Torpedo School in Kronstadt on Kotlin Island.
The naval facility's excellent library and laboratories allowed Popov to pursue research in his area of interest, the new field of "Hertzian waves" (radio waves). In 1888 Heinrich Hertz had demonstrated the generation and reception of radio waves. Beginning in the early 1890s Popov conducted experiments along the lines of Hertz's research.
On 1 June 1894, British radio researcher Oliver Lodge had demonstrated the transmission of radio waves over a distance of 50 meters, using as a receiver a primitive detector called a coherer, a glass tube containing metal filings between two electrodes. When radio waves from an antenna were applied to the electrodes, the coherer became conductive. It allowed the current from a battery to pass through it, which Lodge detected with a galvanometer. After receiving a signal the coherer had to be reset to the nonconductive state by tapping it mechanically, before it would receive again . Lodge's device used an arm rotated by a motor to continually shake the coherer to reset it. Although the spark gap transmitter that generated the radio waves had a telegraph key, there is no indication Lodge ever transmitted a Morse code message to his receiver, only random strings of pulses. So Lodge cannot be credited with the first radio communication.
Popov read of Lodge's experiments, and set to work to design a longer-range receiver that could be used as a lightning detector, to warn of thunderstorms by detecting the electromagnetic pulses of lightning strikes. He built a coherer receiver which improved on Lodge's design by automatically resetting the coherer to its receptive state after each signal.
How it worked
See circuit diagram, right. 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). When a radio signal 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. When the arm sprang back, it tapped 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. In a perhaps more significant innovation, he connected his receiver to a wire antenna (A) suspended high in the air and to a ground (earth) (G). Lodge, Hertz and other earlier researchers had used small dipole or loop antennas, so Popov is credited with the invention of the monopole wire aerial.
Unknown to Popov, in Italy beginning in 1894 Guglielmo Marconi had been experimenting with radio communication with equipment remarkably similar to Popov's; a spark-gap transmitter and an automatically-reset coherer receiver. By mid-1895 he had transmitted messages 2400 meters. Other researchers who had transmitted radio waves were Jagadish Chandra Bose (1894, 100 meters), and Roberto Landell de Moura (1893, 5 miles) in Brazil.
On 7 May 1895 Popov demonstrated his receiver to the Russian Physical and Chemical Society in St. Petersburg, showing it could receive radio signals from a spark gap transmitter. Most Eastern sources regard Popov as the first person to communicate by radio, and the 7th of May has been celebrated since 1945 in the Russian Federation as "Radio Day". However, there is no evidence Popov's receiver was used to receive an actual intelligible message on that occasion. The first account of communication by Popov was a demonstration on 24 March 1896 at the Physical and Chemical Society, when some accounts say the Morse code message "GENRICH GERC" ("HEINRICH HERTZ" in Russian) was received from a transmitter 250 meters away and transcribed on the blackboard by the Society president. An extensive investigation by Charles Susskind in 1962 concluded that Popov did not receive intelligence with his receiver before mid-1896. By mid-1896, Marconi had transmitted radio messages over a kilometer so most Western sources give priority to Marconi. Since Kronstadt was a military institution, Popov had signed a non-disclosure agreement, and people were not allowed to talk about the experiments until years later, so no contemporary sources exist to resolve the issue.
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. Petersberg. 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 Hogland island (Suursaari) to provide two-way communication by wireless telegraphy between the Russian naval base and the crew of the battleship General-Admiral Apraksin. The battleship ran aground on Hogland island in the Gulf of Finland in November, 1899. The crew of the Apraksin were not in immediate danger, but the water in the Gulf began to freeze. Due to bad weather and bureaucratic red tape, the crew of Apraksin did not arrive until January 1900 to establish a wireless station on Hogland Island. By February 5, however, messages were being received reliably. The wireless messages were relayed to Hogland Island by a station some 25 miles away at Kymi (nowadays Kotka) on the Finnish coast. Kotka was selected as the location for the wireless relay station because it was the point closest to Hogland Island served by telegraph wires connected to Russian naval headquarters.
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 Hogland Island wireless station. Besides the rescue of the Apraksin's crew, more than 50 Finnish fishermen, who were stranded on a piece of drift ice in the Gulf of Finland, were saved by the icebreaker Yermak following distress telegrams sent by wireless telegraphy. In 1900, Popov stated (in front of the Congress of Russian Electrical Engineers),
In 1901 Alexander Popov was appointed as professor at the Electrotechnical Institute, which now bears his name. In 1905 he was elected director of the institute.
Death and legacy
At ITU Telecom World 2011, Mr. Igor Shchyogolev, Minister of Telecom and Mass Communications of the Russian Federation alongside Dr. Hamadoun Touré, Secretary General of the ITU, inaugurated the "Alexander Stepanovich Popov" conference room at ITU's headquarters in Geneva.
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. 
- Smith-Rose, Reginald Leslie (2013). "Alexandr Popov". Encyclopaedia Britannica Online. Encyclopedia Britannica, Inc. Retrieved 6 November 2013.
- McKenna, Joe (2007). "Aleksandr Popov's Contributions to Wireless Communication". IEEE Engineering Hall of Fame. Institute of Electrical and Electronic Engineers website. Retrieved 6 November 2013.
- (author name redacted) (January 1960). "Did Alexandr Popov invent radio?". NSA Technical Journal (US: National Security Agency) 5 (1): 35–41. Retrieved 6 November 2013. declassified 8 January 2008
- 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. 12.2
- James P., Rybak (2010). Oliver Lodge: Almost the father of radio (PDF). Antique Wireless Association. Retrieved 7 November 2013.
- Sterling, Christopher H. (2003). Encyclopedia of Radio, Vol. 1. Taylor and Francis. p. 834. ISBN 0203484282.
- "Aleksandr Popov". IEEE Global History Network. IEEE. Retrieved 21 July 2011.
- The Guglielmo Marconi Case; Who is the True Inventor of Radio.
- Dictionary of Minor Planet Names, 2003, vol.1, p.253
-  Engineering Pioneer Egor Popov
-  Connections: The EERI Oral History Series. Egor Popov
- Alexander Popov: Russia's Radio Pioneer by James P. Rybak
- Short biographies of Popov
- (Russian) Lightning detector and radiostations of Popov's design: history of manufacturing
|Wikimedia Commons has media related to Alexander Stepanovich Popov.|
- Aleksandr Popov, Soviet 1949 biopic watchable and downloadable with Esperanto subtitles
- Grave of A. Popov