Credited to Russia. Credit for inventing radio is contested, chiefly between Popov and Guglielmo Marconi. IEEE recognizes Popov's 7 May 1895 demonstration as a significant contribution to wireless communication, and IEEE Spectrum notes that Popov may have been first but did not patent or commercialize his inventions.
How it began
Aleksandr Popov studied physics at the University of St. Petersburg, joined the Russian Navy's Torpedo School as an instructor in 1883 and from 1890 taught at the Marine Engineering School. He set out to invent an instrument that could detect lightning. On 7 May 1895 he demonstrated his apparatus to members of the Russian Physical and Chemical Society, showing that short, continuous signals could be transmitted and received over a distance of up to 64 meters by means of electromagnetic waves.
Before it existed
Popov built on the experiments of Heinrich Hertz, Oliver Lodge and others, whose work he studied while teaching electrical engineering, mathematics and physics at the naval school. Their research had shown that electromagnetic waves existed and could be detected in the laboratory. Popov's aim was practical: a portable instrument that would respond to the electrical oscillations produced by lightning.
How it works
Popov's receiver consisted of a metal filings coherer that he had developed as the detector element, together with an antenna, a relay and a bell. The coherer responded to electrical oscillation picked up by the antenna, and the relay then rang the bell. Although the device was not at first meant as a means of transmitting messages, it proved the feasibility of radio.
Who pushed back
Popov's claim as an inventor of radio was weakened by his own circumstances. At the Marine Engineering School, part of the Russian Naval Department, he was required to sign a non-disclosure statement about his work, which the IEEE history record describes as detrimental to his claim. IEEE Spectrum summarizes the priority question by saying that Popov may have been first but did not patent his inventions or try to commercialize them.
What lasted
Popov continued his research and in 1901 was appointed director of the St. Petersburg Electro-Technical Institute; he died in St. Petersburg in 1906. In 1945, 7 May was declared Radio Day in Russia in honor of his accomplishments. In May 2005 IEEE dedicated a Milestone plaque for his contribution to the development of wireless communication, which can be viewed at the St. Petersburg State Electrotechnical University.
