From the History of Physics

Alexander Stepanovich Popov

(1859–1906)

N. N. Malov

Alexander Stepanovich Popov, who constructed the world’s first radio receiving installation 50 years ago, lived an outwardly uncomplicated life, yet one rich in scientific content.

He was born on March 16, 1859, in the Urals and received his primary education at the Ekaterinburg Theological School and the Perm Theological Seminary. Already at these initial stages of his education he showed great aptitude for the natural sciences. After completing four classes of the seminary, A. S. Popov entered St. Petersburg University, from which he graduated in 1882 with the degree of Candidate in the Faculty of Physics and Mathematics.

A. S. Popov’s outstanding abilities were noticed by the professors: while still a fourth-year student he was appointed assistant in the department of physics, and after graduating from the university he was retained there to prepare for a professorship.

However, his interest in the practical questions of the electrical engineering then beginning to develop, together with material circumstances, diverted Popov from taking the master’s examinations.

In 1883 he entered the Mine Officers’ Class in Kronstadt as an assistant in electrical engineering and as head of the physics laboratory; he soon began giving independent courses at the Naval Technical School and, somewhat later, in the Mine Class.

It must be noted that in those years there were as yet no electrical-engineering faculties at higher technical educational institutions; the physics laboratory (as well as the scientific library) of the Mine Class was one of the best in Russia in the richness of its equipment and made it possible to develop scientific research on a broad scale.

Having become interested in Hertz’s experiments, Popov repeated and improved them and in 1889 delivered a public lecture in which, for the first time, he expressed the idea that Hertzian waves could be used for communication without wires; and on May 7, 1895, at a meeting of the Russian Physico-Chemical Society, he demonstrated his “thunderstorm indicator,” which was the world’s first radio receiver. Further work on the develop-

…radio communication and its application in the fleet, Popov teaches in the same Mine Officer Class, where he had worked for 18 years.

Popov’s scientific merits were recognized by the scientific and technical community. In 1898 he received a prize from the Russian Technical Society; in 1901 he was elected an honorary member of that society, which in those years stood at the head of the scientific and technical community.

In 1901, a vacancy opened for a professor of physics at the recently organized Electrotechnical Institute in Petersburg.

The Council of the Institute considered it necessary “to find a candidate who, independently of specialized knowledge and a gift for teaching, also possessed irreproachable moral qualities and an authoritative name in science.” The Council found that A. S. Popov satisfied all these requirements better than anyone else, and elected him professor, although Popov did not have a doctoral degree. This fact testifies to the high authority of Popov—as a scientist and as a man—in the scientific and technical circles of Petersburg.

Professorial work, of course, compelled Popov to leave the Mine Officer Class, but he maintained his connection with the fleet by working in the Naval Technical Committee.

In 1905, during the first revolution, the first autonomous Council of the Electrotechnical Institute was organized; on October 9 it elected A. S. Popov director of the institute “as a man incapable of oppression, exceptionally honest, capable of sacrificing everything for the institute except truth and straightforwardness.”

Defending the interests of the Institute, protesting against attempts by the gendarmerie to violate its autonomy, Popov had a number of major clashes with representatives of the authorities. The nervous shocks connected with these clashes had an adverse effect on the state of his health. Returning on the evening of January 11, 1906, from a meeting of the Russian Physico-Chemical Society, which at that meeting had elected him its chairman, A. S. Popov fell ill, and on January 13 died of a cerebral hemorrhage.

On January 16 his remains were buried at Volkovo Cemetery in Petersburg.

The invention of radio, like any other invention, is not an accident and is to a significant degree prepared by the preceding development of scientific and technical thought. To evaluate the work of the inventor, one must characterize the conditions under which the invention was made, and also determine to what extent the inventor’s idea has been preserved in the modern, improved form given to the invention in subsequent years.

It is of interest to note that over the course of many centuries—from antiquity to the middle of the nineteenth century, when the telegraph was invented (Morse, 1838) and the telephone (Bell, 1876)—despite significant progress in science and technology, there was practically no progress in the development of means of communication.

A. S. Popov.

The increasingly complex and accelerating economic and political life of human society, the expansion of industrial, commercial, and cultural relations, and progress in the field of transport ensured the very rapid development of telegraph and telephone communication. By the beginning of the twentieth century, the globe was encircled by 9 million km of telegraph wires; the length of cables reached 300,000 km; and the number of telephone sets reached several million.

But all these types of communication began to hamper the development of the national economy, proving unsuitable in a whole series of cases (above all when it was necessary to communicate with rapidly moving crews, and also at sea).

The need for communication without wires became ever more significant; a scientific basis for its realization was also being prepared.

The discovery of electromagnetic induction (Faraday, 1831) made wireless communication possible in principle. But the rapid decrease of the induction effect with distance did not permit satisfactory results to be obtained.

Maxwell’s theoretical works, dating from the 1860s, in which Faraday’s ideas received further development and mathematical formulation, contained the prediction of the possibility of the existence of electromagnetic waves in a dielectric. Hertz’s classical experiments (1887) brilliantly confirmed this prediction. Hertz also made the first calculation of the radiation field of a dipole. At present it is clear to us that communication over large distances is possible at a sufficiently high frequency of oscillations (or, what is the same thing, with sufficiently short pulses), since only in this case will the energy of the pulse be concentrated in a sufficiently small volume of space and the field will decrease as the first power of the distance already at a small distance from the radiator (contraction of the “near zone” of radiation), and therefore can retain an appreciable magnitude far from the transmitter.

Hertz and his closest successors had transmitters of negligible power at their disposal; in their experiments they did not go beyond the confines of laboratory rooms; Hertz’s receiving device—the spark gap—was very insensitive.

The coherer invented by Branly (1891), in which the change in the resistance of a metallic powder under the action of an alternating electric field is used, required shaking after each received signal, which made experimentation with it difficult.

Popov’s merit lies in the fact that, having mastered the experience of all his predecessors, he not only improved parts of the apparatus used, but very successfully combined them in his circuit of the “thunderstorm indicator”—the world’s first radio receiver, which registered thunderstorm discharges (in 1894—1895 Popov did not yet have a radiator of any considerable power).

In the circuit of the lightning recorder (see the figure), when a signal is received the resistance of the coherer decreases and the circuit of the auxiliary relay is closed; this relay, in operating, closes the circuit of the electric bell; the hammer of the latter not only produces a sound by striking the bell, but at the same time, striking the coherer, shakes it and makes it ready to receive further signals. The receiving circuit also contains a long wire—the prototype of the modern antenna—which ensures the extraction of considerable energy from the field of the passing electromagnetic wave.

Thus, the circuit of the lightning recorder contains the most important elements of a radio-receiving circuit: an antenna, feedback (the received signal automatically brings the coherer into working condition), and a relay, in which the modern principle of amplification is reflected.

In the lightning recorder only the principle of resonance was not used; but, since the question concerned the reception of thunderstorm discharges, whose spectrum is insufficiently studied even in our time, the phenomenon of resonance could not have been used.

Even later, when radio communication began to develop, the phenomenon of resonance was not employed immediately, since at that time it was impossible to take account of the influence of the antenna on the frequency being emitted (or received), and methods for measuring frequency did not exist.

Circuit of the lightning recorder.

Thus, the circuit of the lightning recorder contained all the most important elements of a receiving circuit, and therefore it should be regarded as the world’s first radio receiver, and the reception carried out with its aid as the world’s first radio communication; the range of this radio communication was 25–30 km.

At the first public demonstration of the lightning recorder at the Russian Physico-Chemical Society, held on May 7, 1895, Popov expressed confidence that further improvement of the receiving device and the development of sufficiently powerful emitters would make it possible to carry out communication without wires over considerable distances. Ten months later, on March 24, 1896, in the same society Popov demonstrated an improved receiver, in which the bell was replaced by a telegraph apparatus, and received from a distance of about 250 m the world’s first radiogram: “Heinrich Hertz.”

In the following years Popov carried out experiments on radio communication in the navy, systematically increasing the range and reliability of transmission. Of great importance for the development of radio communication was the discovery of the possibility of receiving weak radio signals by telephone, made on June 10, 1899, by Popov’s assistant, the now happily living P. N. Rybkin, which made it possible sharply to increase the operating radius of radio communication. The Naval Ministry did not take account of the significance of Popov’s discovery and financed his work rather meagerly, which, of course, hindered its development.

Nevertheless, when on November 13, 1899, the battleship General-Admiral Apraksin ran aground on rocks in the Gulf of Finland, 45 km from shore, and communication with it proved very difficult, since the gulf was freezing over, Popov was asked to set up radio communication between the battleship and the mainland, which he accomplished brilliantly. The world’s first permanently operating two-way radio link was opened on February 6, 1900; in 84 days 440 official radiograms were transmitted. It is interesting to note that the first radiogram transmitted to the battleship contained an order to the icebreaker Yermak, which was near the battleship, to go in search of fishermen carried out to sea on a detached ice floe, and saved several dozen human lives.

Popov’s work on radio communication in the navy was highly valued by the most outstanding leaders of the fleet, among whom one should note Vice-Admiral Makarov, the well-known builder of icebreakers, who throughout his life fought against the bureaucratic routines that hindered the growth of the fleet’s combat power, and who perished in the first months of the siege of Port Arthur.

But the leadership of the fleet as a whole did not give Popov sufficient attention. As a result, Popov’s technical achievements—his consultation was also used by the small French firm Ducretet—were soon overshadowed by the English firm of Marconi, which possessed far greater material resources than the modest laboratory and workshops of the Mine Officers’ Classes in Kronstadt.

As the enormous practical value of radio communication became clear, the question of priority in its invention began to assume unhealthy forms. The young Italian Marconi brought to England in 1896 sealed boxes with the aid of which he effected communication over short distances. Having interested influential English circles with his experiments and organized a joint-stock company, Marconi took out a patent on his invention; this patent, published in 1897, contained a circuit completely coinciding with the circuit of the lightning detector demonstrated by Popov, as already indicated, on May 7, 1895, and published in the January issue of the journal of the Russian Physico-Chemical Society for 1896. It is difficult to say whether borrowing took place here or whether it was an accidental coincidence, but the difference in the time of publication of the two circuits is so significant—

ALEXANDER STEPANOVICH POPOV

but that, in essence, no disputes over priority should arise.

The English organizations that issued patents apparently did not read Russian journals; but in Germany Marconi’s patent was refused, and in the United States, in the Supreme Court, when one of Marconi’s patent claims was being examined, it was emphasized that “Marconi was not the inventor of radio.”

In 1900 Popov received a gold medal at the World Electrotechnical Congress in Paris. In 1903 he took part in the work of the First International Radiotelegraph Conference, where, as Popov wrote to his wife, “at the opening my name was mentioned in the proper place and in the proper form, ahead of Marconi...”

In manuals on radio engineering published at the beginning of the twentieth century, Popov’s name was mentioned; later, however, when the great successes of the Marconi firm overshadowed the first steps of radio engineering associated with Popov’s name, after his death and the death of the physicists who had known him, authors, as often happens, did not take the trouble to study the history of the question with sufficient care, and Popov’s name began to be forgotten.

In 1908 the question of Popov’s priority was taken up by a commission of the Russian Physico-Chemical Society under the chairmanship of Prof. O. D. Khvolson. It consulted a number of the most eminent physicists of that time, studied the available documents and, noting Popov’s priority, stated in its decision that “it was not A. S. Popov who could have borrowed from Marconi, but the reverse.”

On the day of the fiftieth anniversary of the invention of radio, it is time, at last, to put an end to the discussion of the question of priority, which in essence has no basis whatsoever.

After the death of A. S. Popov, the development of radio communication continued at a very rapid pace. The testing of radio communication during the Russo-Japanese War proved its military significance. The appearance of the electron tube and the transition to communication by undamped oscillations made it possible to carry out radiotelephony and to develop radio broadcasting and television. The continuous improvement of radio apparatus enriched science and technology with new methods for investigating and utilizing the forces of nature. Radio-engineering methods penetrated the most varied branches of science and technology. Vacuum-tube amplifiers found application in the most diverse fields; the development of electron optics made it possible to obtain magnifications hundreds of times greater than those given by ordinary microscopes; radio waves proved to be a very effective means for studying the ionosphere; generators of electromagnetic oscillations found application in metallurgy, the food industry, medicine, and so on. Radio signals are widely used in aeronautics (radio beacons, control of the blind landing of aircraft); a new field of radio engineering arose—radar—which played a major role in the present war; experiments continue on the remote control of mechanisms. The role of communications in military operations has grown enormously.

Thus, in the Battle of Stalingrad up to 9,000 radio stations took part on our side, and in the operations for the liberation of the Byelorussian SSR—up to 30,000 radio stations.

The Soviet radio industry, created after the October Revolution, is successfully coping with the tasks facing it. For many years the Soviet Union possessed the most powerful radio stations (the 100-kilowatt VTsSPS radio station, the 500-kilowatt Comintern station, and the super-powerful radio station built in 1943) and a widely developed broadcasting network.

The experiments of A. S. Popov served as the foundation for the development of the remarkable achievements noted above; therefore the entire Soviet Union proudly and gratefully honors the memory of the outstanding scientist-patriot who, in response to a proposal to realize his invention abroad, declared: “I am a Russian man, and all my knowledge, all my labor, all my achievements I have the right to give only to my Motherland.”