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Alexander Stepanovich Popov was Russian physicist and electrical engineer, known of his investigations of electromagnetic waves and receiving them over long distances. Popov was the first who used an antenna in the transmission and reception of radio waves. He constructed an apparatus that could register atmospheric electrical disturbances and was interested in X rays.
Popov was acclaimed in Russia as the inventor of radio but its priority has not been generally accepted; Marconi’s priority is usually conceded. Alexander Stepanovich Popov was born on March 16, 1859 in the village of Turinsk, mining district in the Ural Mountains. A popular Russian biography of Popov says he grew up in a household filled with those haunting Russian icons of martyred saints. The boy Popov, it’s reported, was “blessed by the Lord” with the strong desire to be able to communicate silently and invisibly through air by means of some as yet undiscovered and incomprehensible process.
“In the long winter nights of the Ural Mountains, while the wind sang its song outside, the boy was preparing for his destiny - to be the inventor of radio.” As a boy, Alex was intrigued by the many types of iron mining and manufacturing machines he saw functioning in the vicinity. He often spent his spare time building small but quite sophisticated working models of the water powered machines he had seen. Very early in his life, Alex became interested in the study of natural science.
House where Popov lived being a student of the seminary in Ekaterinburg, now Popov’s Radio Museum
Popov’s father was a village priest who encouraged all seven of his children to get a good education. Alexander completed his elementary education in two years and then entered the ecclesiastical seminary at Ekaterinburg to prepare for the priesthood.
The seminary provided him with a good education in the natural sciences and mathematics as well as in theology. It was here that Alexander Popov became fascinated by the study of physics. His interests were rapidly shifted to physics and mathematics and then to electrical engineering.
After completing his seminary education, Popov enrolled in the Faculty of Physics in the St. Petersburg University to continue his study of physics and mathematics. The curriculum at the University was modern and emphasized heavily the practical applications of scientific principles. Alexander Popov excelled at experimental work. He seemed to have a natural aptitude and love for designing and building laboratory equipment.
Popov spent every available moment conducting experimental investigations with the equipment he built. Scientific knowledge concerning electricity was expanding rapidly in the 1880’s. This was the area of physics Popov knew he wanted to pursue. The superior experimental research talents of Alexander Popov were readily apparent to the physics faculty at the St. Petersburg University.
Upon graduating with distinction in 1882, he was offered the opportunity to stay on at the University as a laboratory assistant. Alex readily accepted this position because it enabled him to remain close to the laboratories and the work he loved.
Funds for teaching and research at the University were meagre, however. Popov, having a family to support, accepted a more promising position in 1883 at the Russian Navy’s Torpedo School located at Kronstadt. The Kronstadt naval base located on Kotlin Island in the Gulf of Finland was the home of Russia’s Baltic fleet.
The Torpedo School offered an outstanding program of study in applied physics for naval electricians (electrical engineers) and torpedo officers. It had the best scientific library and physics laboratories in Russia. Here Popov found the better environment for experimental research he wanted and needed. His early laboratory investigations at Kronstadt involved magnetic phenomena and electrical heating effects in metals.
In the late 1880’s, the use of electrical power on ships was beginning to be introduced in Russia. A problem soon was noted when electrical wiring was routed along the metal hulls of the ships. Sparks which damaged the electrical insulation were observed where they were least expected. Popov determined that the sparking was due to large voltages produced by unanticipated high frequency oscillations. Today, we would identify resonance as the cause of the sparking.
At the time, however, the phenomenon of electrical resonance was not understood. These findings turned Popov’s interests toward the practical applications of high frequency currents and the invisible electromagnetic waves produced by those currents. Very quickly, Popov became aware that Hertzian wave theory might well provide a means for finding solutions to many electrical engineering problems.
Alexander Popov’s knowledge of electrical progress being achieved throughout the world was not limited to what he read in foreign journals. In 1893, he was sent as the representative of the Torpedo School to the Chicago World Exhibition where the latest developments related to the generation, distribution, and utilization of electrical energy were on display.
While in the United States, Popov also took the opportunity to visit factories and laboratories where numerous other recent achievements in the rapidly developing field of electrical technology could be seen first hand. Even among the most highly optimistic electrical visionaries of the early 1890’s, the idea that electromagnetic waves might someday enable telegraphy without wires was little more than a wild fantasy. After all, the electromagnetic waves being generated at that time could be detected at distances of only a few feet, not the many miles which would be necessary to make wireless telegraphy a practical reality. Fortunately, Popov was both a visionary and an excellent experimenter who could not be discouraged easily by seemingly insurmountable obstacles.
By 1894, Popov had succeeded in making a reliable generator of electromagnetic waves. The receiving or detecting systems in common use, however, were not at all satisfactory. The problem of finding a detector which was both sensitive and reliable was one which plagued all who experimented with Hertzian waves at that time.
Heinrich Hertz had used a wire loop resonator equipped with an adjustable spark gap as a detector when he demonstrated the existence of electromagnetic waves in 1888. Two years later, the French scientist Edouard Branly observed that the electrical resistance of fine metal particles decreased dramatically when a spark discharge occurred nearby.
A non-conducting tube containing metal particles packed between two electrodes came to be known as a “Branly tube” detector. It was a much more sensitive detector than was Hertz’s wire loop. However, the metal particles in the Branly tube had to be shaken or “tapped back” between each electrical discharge in order to restore the detecting ability of the tube. Oliver Lodge, an English physicist, noticed in 1892 that the contact between two small metal spheres, barely touching each other, ordinarily was not sufficient to permit a current to flow.
However, when a spark discharge occurred near them, the spheres became fused together and current could easily flow through the junction. The spheres would remain joined until lightly tapped. Lodge called the phenomenon he had observed the “coherer” effect. Initially, he was unaware that he was observing the same effect noted by Branly. Like Branly, Lodge at first saw no use for the effect. Very soon, however, Lodge realized that the coherer effect both Branly and he had observed could be utilized to detect the presence of the electromagnetic waves produced by a distant spark discharge.
Alexander Popov had read in scientific journals of Lodge’s work. Popov further improved the sensitivity of the coherer tube and developed a signal-actuated tapping mechanism for restoring its detecting ability. He found through experimentation that platinum foil electrodes together with iron powder of a particular fineness resulted in increased sensitivity of his coherer tube.
The “tapping back” arrangement Popov devised was comprised of a relay and a doorbell mechanism. When the coherer tube was made highly conductive due to the presence of a Hertzian wave, a dc current sufficient to close the relay was caused to flow. This closing of the relay, in turn, allowed current to flow to the bell mechanism. The bell hammer struck the bell on the first half of its cyclic motion and gently struck or “tapped” the coherer tube on the second half.
Tapping the coherer tube in this manner reliably “decohered” the iron powder, causing its resistance to increase to its original high level. This reduced the current through the relay to the point where the relay contacts opened and the bell mechanism was no longer activated. Thus, an electromagnetic wave caused its own presence to be signaled briefly by the bell and also made the coherer ready to detect the next wave.
Popov found that he could detect distant atmospheric lightning discharges by connecting one end of the coherer to a wire antenna and the other end to a good earth ground. The coherer and the relay also were used to activate a pen mechanism recording device. The pen made a mark on a slowly rotating cylinder when a lightning discharge occurred.
It was this lightning detection apparatus that Popov demonstrated to the members of the Russian Physical and Chemical Society on May 7, 1895. On this day, Alexander Popov presented a demonstration which would become recognized as an historic achievement. This demonstration, together with another by Popov which reportedly took place the following year, eventually would produce controversy among historians concerning whether the credit for “inventing” radio should be given to Marconi or to Popov.
Those in attendance for Popov’s May 7 presentation were very much impressed when he demonstrated a receiver which could detect the electromagnetic waves produced by lightning discharges in the atmosphere many miles away. The value this instrument could have in weather forecasting was obvious. While this demonstration by Popov did not involve the transmission and reception of a message, it nonetheless was a significant scientific achievement for that time.
Clear written records of the event were made and preserved. Later that same summer, he set up his thunderstorm detecting and recording instrument at the Institute of Forestry in St. Petersburg. With Popov’s equipment, lightning discharges occurring as far away as 20 miles were detected. Each year on May 7, the Soviet Union and now Russia still celebrates “Radio Day” to commemorate the achievements of Alexander Popov.
Popov’s radio receiver and its electrical scheme (right)
Popov’s receiver consisted of a metal filings coherer he had developed as the detector element together with an antenna, a relay, and a bell. The relay was used to activate the bell which both announced the occurrence of a lightning discharge and served as a “decoherer” (tapper) to ready the coherer to detect the next lightning discharge.
During 1896, teaching responsibilities and the desire to conduct experiments with the recently discovered Roentgen rays (X-rays) kept Popov busy. He had little time to devote to new electromagnetic wave experiments.
On 12th of March 1896 Popov together with Ribkin demonstrated wireless transmission of Morse signals from one university building to another that was 200 meters far from the first one. It was the first sensible transmission of text in the world. Reports also exist that some ten months later on March 24, 1896 Alexander Popov demonstrated the transmission and reception of information by wireless telegraphy.
The occasion was another meeting of the Russian Physical and Chemical Society and the location was the St. Petersburg University. Wireless telegraph signals, transmitted a distance of over 800 feet from another building on the campus, were audible to all in the meeting room. The President of the Society, F. F. Petrushevsky, stood at a blackboard holding a paper on which a listing of the letters of the alphabet and their equivalents in Morse Code were written.
As the signals were received, Petrushevsky referred to the paper and wrote the appropriate letter on the blackboard. The letters spelled out the name “HEINRICH HERTZ” – the name of a great German physicist who first convincingly demonstrated the existence of the electromagnetic waves predicted in 1864 by James Clerk Maxwell. Unfortunately, no written record was made at the time of this wireless telegraphy demonstration to provide documentation for historical purposes.
The reports of the event which do exist are based on the recollections of several persons present at the time, but were not recorded until almost thirty years later. In spring of 1897 Popov conducted some experiments on the ships and was able to transmit information to a ship that was as far as 640 meters from Popov. He was increasing the distance of transmission day by day.
Articles appeared in Russian newspapers beginning in October of 1896 concerning experiments which were being conducted in other countries with the goal of developing practical wireless telegraphy. Upon reading these articles, Popov was both surprised and somewhat annoyed by the way journalists were treating this “news.” What was being reported with great interest by the press were two announcements made at the recent meeting in Liverpool, England of the British Association for the Advancement of Science.
The first announcement reported was that J. C. Bose, whose laboratory was in Calcutta, had demonstrated an instrument for the detection of Hertzian waves. A description of Bose’s work already had appeared in the scientific journals which Popov read regularly. Popov knew that Bose’s instrument was very similar to the one he himself had been using for over a year at the Institute of Forestry to detect lightning discharges. There was nothing new in Bose’s work as far as Popov was concerned.
The second announcement of interest at the Liverpool meeting had been made by William Preece, chief engineer for the British Post Office. He reported that a Mr. Marconi, from Italy, recently had come to England and had succeeded in sending telegraph signals a distance of one and one-quarter miles without wires. Alexander Popov could not understand why so much attention was being given to this “Mr. Marconi.” For some time, Popov had maintained that wireless telegraphy would one day be a reality.
The demonstration of his thunderstorm detecting instrument to the Russian Physical and Chemical Society which occurred on May 7,1895 had been described by Popov in the January 1896 edition of that organization’s journal. At the end of the article, Popov had stated: “In conclusion, I may express the hope that my apparatus, when further perfected, may be used for the transmission of signals to a distance by means of rapid electric vibrations if only a source of such vibrations can be found possessing sufficient energy.”
In the process of developing his lightning discharge detector, Popov very apparently had tried to send wireless signals (but evidently not “messages") over extended distances as early as 1895. He had found the range attainable to be very limited. Popov incorrectly had assumed that transmitter power, rather than receiver sensitivity, was the important factor in establishing wireless telegraphy.
Popov was somewhat irritated when he read of the attention that was now being paid to Marconi’s wireless telegraphy achievements. He knew that his own earlier work was very similar to that for which Marconi now was getting loud acclaim. The feelings of irritation Popov felt, however, were directed at himself, not toward Marconi. Popov knew he should have pursued his own wireless work more vigorously and with greater persistence.
Popov felt no personal resentment toward Marconi. In 1902 when Marconi visited Kronstadt, Popov met with him and the two wireless pioneers had a very cordial discussion. Marconi later received a silver samovar and a sealskin coat from Popov as wedding presents. Popov was much too much of a true scientist and a gentleman to harbor personal grudges over the legitimate scientific successes of another.
It is claimed by his proponents that Popov conceived of the principles of wireless and even demonstrated it in rudimentary fashion prior to Marconi. Why then is it that Popov, unlike Marconi, did not refine and promote his concept? Alexander Popov was first and foremost an academician, not an entrepreneur. He loved to learn and he loved to help others to learn. Knowledge and understanding of the physical principles which governed the world in which he lived was Popov’s goal. Popov believed in “science for the sake of science,” not in “science for personal profit.” Limiting the ability of others to make use of scientific discovery by filing for protective patents was a concept foreign to Popov.
Personal modesty and a reserved nature also were strong characteristics of Popov. He was reluctant to describe his scientific achievements to others for fear he would be thought of as a braggart and self-promoting. Popov particularly was reluctant to describe to others an accomplishment of his which was still in its preliminary stages. The thought of orchestrating a scientific demonstration in order to make headlines in the newspapers and receive public recognition probably would have turned Popov’s stomach.
Marconi, on the other hand, truly was an entrepreneur. He enjoyed the challenge of developing technology to produce things the world needed and would buy.
Obtaining patent protection for the technology he developed was critically important for protecting his investment of time and money. Another important element for success as an entrepreneur is getting public recognition for the product and the company producing it. Marconi understood this well and acted accordingly. He seldom missed an opportunity to have the press report with large headlines a demonstration he had given of his scientific achievements. Marconi understood human nature as well as he understood technology.
While Popov thoroughly enjoyed his scientific research and devoted countless hours to it, he did not approach it with a sense of urgency. Developing wireless telegraphy was of great interest to Popov but so were other scientific topics such as the newly discovered Roentgen rays. Marconi, in contrast, was single-minded in his determination to develop wireless telegraphy into a commercially useful technology. His goal was not merely to bring new scientific knowledge to the world.
Rather, Marconi sought to provide the world with a new technology which would serve a need and which would bring to him both fame and fortune. He had to pursue his goal without delay lest someone else achieve it first. Marconi not only believed that signalling without wires was possible, he had the vision and will to make that belief a reality.
The differences in attitudes and motivations between the two men were important in determining the way each approached his work. However, it probably was a key scientific observation made by Marconi early in his work which ultimately enabled his continued progress toward and success in perfecting wireless telegraphy. Marconi had discovered that if both his receiver and transmitter were each connected to earth grounds and wire antennas, the distances over which electromagnetic waves could be sent and detected increased tremendously.
Popov, however, seemingly did not realize at first that the earth ground and antenna connections which enabled his receiver to function well when detecting lightning discharges also were critically important to having his transmitter function well. Without this realization, Popov could not send electromagnetic waves over significant distances. Perhaps this lack of success at transmitting signals over significant distances helps explain why Popov shifted his attention to other work during much of 1896.
The publicity accorded to Marconi abruptly shook Popov out of whatever state of inaction he was in concerning his own wireless telegraphy work. Popov now undertook a deliberate effort to make his earlier wireless accomplishments better known to other Russian scientists. He also resumed in earnest his own work toward the development of a practical wireless telegraphy system. When specific details of Marconi’s 1896 work were published in 1897, it became apparent that Marconi’s receiver was of very similar design as that which Popov had used to detect lightning discharges in 1895.
However, there never was any accusation on Popov’s part that Marconi had “copied” his receiver design. Unquestionably, Marconi knew nothing of Popov’s work. The coherer was the only practical detector of Hertzian waves then available and the published reports of its use as such by Lodge were known to both Marconi and Popov. It is not surprising, therefore, that both Popov and Marconi would develop nearly identical receivers.
The United States Navy, which battled with Marconi over the use of his patents on US warships, gives Marconi credit for his marketing prowess, but Popov gets credit for being a better scientist. Here’s how the official U.S. Government publication History of Communications - Electronics in the United States Navy (Bureau of Ships and Office of Naval History, 1963) views the question of who invented radio: “[In 1895], Prof. A.S. Popoff improved [Sir Oliver] Lodge’s receiver by the insertion of choke coils on each side of the relay to protect the coherer and by replacing the spark gap with a vertical antenna insulated at its upper end and connected to the ground through the coherer.
Popoff utilized his equipment to obtain information for a study of atmospheric electricity. Like Lodge, he was too engrossed with teaching and science to concern himself over its practical aspects. On 7 May 1895, in a lecture before the Russian Physicist Society of St. Petersburg, he stated he had transmitted and received signals at an intervening distance of 6 hundred yards.
In the same year, Guglielmo Marconi, son of an Italian nobleman and an Irish mother, by using a Hertz oscillator and an antenna and a receiver very similar to Popoff’s, successfully transmitted and received signals within the limits of his father’s estate at Bologna, Italy.
Marconi can scarcely be called an inventor. His contribution was more in the fields of applied research and engineering development. He possessed a very practical business acumen, and he was not hampered by the same driving urge to do fundamental research which had caused Lodge and Popoff to procrastinate in the development of a commercial [radio] system.”
In 1897 Popov also discovered that all metal objects in the way of a radio wave could change the wave direction, or in other words could reflect it. It was the start of another useful invention called later radio-location.
Imperfection of equipment at that time did not allow to put the observation into use until 40 years later when the first radio-radar was built. Others have laid claims that they discovered this phenomena of wave reflection, but it should be remembered that the invention was actually made by Popov. American and British companies often asked Popov to sell his invention but his reply was always: “I am Russian and I have the right to give all my knowledge, my achievements and inventions to my fatherland only".
Popov wanted to demonstrate to the Russian Navy the value wireless could have for communicating with and between ships. The Tsar’s admiralty responded slowly to his offers to demonstrate the capabilities of wireless. By 1899, however, Popov had successfully carried out demonstrations of wireless telegraphy communications to a distance of 20 miles between ships of the Black Sea fleet.
Battleship General-Admiral Apraksin, 1899
If the Russian Navy had any remaining doubts concerning the value of wireless telegraphy, Popov dispelled them when the battleship General-Admiral Apraksin ran aground on Gogland Island in the Gulf of Finland in November of 1899. Efforts to free the ship had to be started immediately. The crew of the Apraksin was in no immediate danger but the water in the Gulf was beginning to freeze. If the ship survived without serious damage until spring, it likely would be crushed by moving ice floes.
No direct means of communication existed between Gogland Island and the mainland. Word of the Apraksin’s predicament had been relayed by another ship. Because the Gulf of Finland was beginning to freeze over, it was not possible to lay a submarine cable to communicate with the ship and coordinate the effort to free it. Popov’s wireless equipment provided the only option.
Due to bad weather and bureaucratic red tape, the crew to establish a wireless station on Gogland Island did not arrive there until January of 1900. By February 5, however, messages were being received reliably. The wireless messages were relayed to Gogland Island by a station some 25 miles away at Kotka on the Finnish coast. Kotka was selected as the location for the wireless relay station because it was the point closest to Gogland Island served by telegraph wires connected to Russian naval headquarters.
Icebreaker Yermak
A distress alert was one of the first wireless message received on Gogland Island. An ice-floe with 50 Finnish fishermen on it had broken loose nearby in the Gulf of Finland. Little time could be lost if these 50 lives were to be saved. The icebreaker Yermak which had brought supplies and was trying to free the Apraksin was immediately ordered to go to the aid of the stranded fishermen. Little more than 24 hours after the wireless message had been received, the rescue of all 50 persons had been accomplished.
By the time the Apraksin was freed from the rocks at the end of April, 440 official telegraph messages had been handled by the Gogland Island wireless station. The indisputable value of wireless telegraphy to any navy now should have been clear to the Russian admiralty.
Popov continued his efforts to develop a wireless telegraphy capability for the Russian Navy. Despite the seemingly convincing demonstrations Popov had provided, the Tsar’s naval bureaucracy was not very receptive to innovation. Prior to 1900, Popov had urged the Russian Navy to establish a wireless equipment manufacturing facility and to begin the training of wireless operators.
His recommendations were accepted in principle but were given only the minimum financial support. The wisdom of Popov’s recommendations became evident, however, when the Russo-Japanese War seemed imminent in 1904 and the Russian Navy had to purchase from Germany the wireless equipment it needed.
Grand Gold Medal, Paris, 1900
Popov’s radio system earned him a Grand Gold Medal for research at the Paris International Exposition of 1900. Popov’s outstanding capabilities as a teacher and scientist won him a professorial appointment at the Imperial Institute of Electrical Engineering in St. Petersburg in 1901. In September of 1905, he was elected Director of that Institute.
Unfortunately, the political situation in Russia was very unsettled in 1905. As the country moved dangerously close to civil war, the Tsar’s policies became more and more reactionary. Popov, always a strong believer in the principles of academic and political freedom, found the oppressive climate in St. Petersburg a very difficult one in which to function.
When Popov was ordered by the government to take repressive measures against the growing student movement at the Electrotechnical Institute, he became very upset. Popov’s health never had been robust due to the strenuous pace he always had set for himself. The thought of having to take measures against what he considered to be legitimate student activities was too much. Alexander Stepanovitch Popov fell seriously ill on January 10, 1906 and died of a brain hemorrhage on January 13 at the age of 46.
Determining who has claim to the title “Inventor of Radio” is complicated somewhat by issues of nationalistic pride, inadequate documentation of events, and differing interpretations of what constitutes “inventing” radio. By what most persons in the West consider “objective” analysis of the facts known, however, Marconi’s work invariably is recognized as having priority over Popov’s. Nonetheless, Popov’s numerous achievements do merit both recognition and respect.
Popov was given remarkably little support by the Russian government until 50 years later, when national attitudes and enthusiasms had changed. On May 7, 1945, the Bolshoi Theatre was packed with a distinguished audience to celebrate the 50th anniversary of the “invention of the radio” by A.S. Popov. On the stage sat scientists, marshals, admirals, commissars, leaders of the Communist Party, and Popov’s daughter. It was announced that in the future the 7th of May would be celebrated as the day of the radio.
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