Alexanderson, Ernst Frederik Werner (1878–1975)

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ALEXANDERSON, ERNST FREDERIK WERNER (1878–1975)

Ernst F. W. Alexanderson was a Swedish American engineer and inventor who is best remembered for his pioneering work on the high frequency alternator that made long-distance radio communication possible. He was born on January 25, 1878, in Uppsala, Sweden. His father, Aron M. Alexanderson, taught classical languages at the University of Uppsala and was later chair of classical languages at the University of Lund. Alexanderson's mother was the former Amelie von Heidenstam. The young Alexanderson was educated at Lund High School and then at the University of Lund (between 1896 and 1897). He continued his studies at the Royal Institute of Technology in Stockholm, and later, in Berlin, he studied under the instruction of Adolf K. H. Slaby, the inventor of a primitive form of radio communication.

Alexanderson was anxious to put his knowledge to practical use. America, which seemed at that time to be the fountainhead of many important technological advancements, beckoned. Arriving in New York in 1901, he immediately went to work as a draftsman for the C. & C. Electrical Company in New Jersey. Alexanderson sought out and was quickly befriended by the esteemed inventors Thomas Edison and Charles Steinmetz. In 1904, after passing General Electric's engineering exams, he became a member of that company's engineering staff.

Alexanderson's big break came when he was commissioned by Reginald Fessenden, a pioneering wireless operator, to build a generator that could produce alternating, high frequency currents. These currents would be used to generate a continuous, dependable wave for radio transmission and thus enable a broadcast of more complexity. On Christmas Eve of 1906, Alexanderson's invention was used to broadcast the first radio show that featured singing and conversation.

Guglielmo Marconi, the Italian engineer and inventor, visited Alexanderson in 1915 and bought one of his 50-foot alternators for the transatlantic Marconi Center in New Jersey. Within a few years, Alexanderson's alternators were to be found in numerous countries. Using a 200-foot Alexanderson alternator, Marconi broadcast radio transmissions during World War I that were heard all over Europe.

In 1916, Alexanderson made another important contribution to radio broadcasting when he unveiled his tuned radio receiver, which allowed for selective tuning. It quickly became an integral part of radio broadcasting.

Alexanderson's alternator played an important part in history when President Woodrow Wilson used it to broadcast his 1918 ultimatum to Germany, ending the war. Afterwards, the Marconi company sought to buy exclusive world rights to the alternator, but was rebuffed by the U.S. government. Wishing to keep control of the invention within American hands, the government set up the Radio Corporation of America (RCA) in 1919, with Alexanderson as its chief head engineer. Concurrently, Alexanderson continued to work for General Electric, an association that lasted forty-six years.

In 1919, he made history with yet another of his inventions when his multiple-tuned antenna, antistatic receiver, and magnetic amplifier were used to transmit the first two-way radio conversation. This great event took place 900 miles out to sea, between the Trans-Atlantic Marconi Company station at New Brunswick and the steamship George Washington, with President Woodrow Wilson on board as a witness.

The magnetic amplifier was outmoded by another Alexanderson invention, the electronic modulator, which used vacuum tubes to help generate high frequency transmitters of great power. Alexanderson also helped to create the amplidyne, a direct current generator. By the use of compensating coils and a short circuit across two of its brushes, the amplidyne uses a small power input to precisely control a large power output. Its system of amplification and control originally was designed for use in steel mills, but later hundreds of other applications, including an adaption to fire antiaircraft guns during World War II. Alexanderson also held patents for his inventions of telephone relays, radiant energy guided systems for aircraft, electric ship propulsion, automatic steering, motors and power transmission systems, railway electrification systems, as well as inventions in the fields of radio and television.

In 1924 Alexanderson began his television research. By 1927 his group was able to broadcast mechanical television into the home and in 1930 General Electric gave the first large screen demonstration of television in a theatre in Schenectady. His team then transferred to RCA where they helped develop our modern system of television.

Alexanderson retired from General Electric in January 1948, although he remained a consultant engineer to the company. In 1952 Alexanderson was consulted for RCA. In all, Alexanderson held 322 patents for his inventions.

Ernst Alexanderson's enormous contribution to technology was acknowledged more than once. Some of the honors and awards he received during his long life are: The Gold Medal of the Institute of Radio Engineers in 1919, the Order of the Polonia Restituta in 1924, the John Ericcson Medal in 1928, the Edison Medal of the American Institute of Electrical Engineers in 1944, the Cedergren Medal of the Royal Institute of Technology of Sweden in 1945, and the Valdemar Poulsen Gold Medal and the Royal Danish Medal, both in 1946. He received honorary degrees from Union College, Schenectady, New York in 1926, and the University of Uppsala in 1938. He was a member, fellow, and later president of the Institute of Radio Engineers, a member and president of the Institute of Radio Engineers, and a member of the Swedish Royal Academy and Sigma Xi. In his spare time and retirement, Alexanderson enjoyed sailing, and was elected the first Commodore of the Lake George Yacht Club in New York. Alexanderson died at the age of ninety-seven on May 14, 1975.

Albert Abramson