Edwin Howard Armstrong (also sometimes referred to as Edwin H. Armstrong, in short) was born December 18, 1890, New York US. Armstrong was an American inventor who laid the foundation for much of modern radio and electronic circuitry, including the frequency modulation (FM) system, and the regenerative and superheterodyne circuits.
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Early Life
Edwin Howard Armstrong belonged to a respectful and devout Presbyterian family of Manhattan. Armstrong’s father was a publisher and his mother was a former schoolteacher. He was a shy young boy interested in railway trains, engines, and all mechanical contraptions from childhood.
Armstrong decided to become an inventor when he was fired by reading of the exploits of Guglielmo Marconi in sending the first wireless message across the Atlantic Ocean, at the time he was only 14 years old. Armstrong began the solitary, secretive work that absorbed his life when he built a maze of wireless apparatus in his family’s attic. He had no other significant interests, except for a passion for tennis and for fast motor cars, which he developed at a later point in time.
At the time wireless was in its infancy stage with spark-gap transmitters and iron-filing receivers, generating faint Morse-code signals, barely audible through tight earphones. After graduating from high school, Armstrong attended Columbia University’s School of Engineering. He then started his hunt for improved instruments.
Armstrong made his first invention which was groundbreaking when he was in his junior year at Columbia. Audion, or three-element vacuum tube, was among the devices investigated for better wireless reception. Back then this was not used so much and understood very little. This device was invented by Lee De Forest in 1906, who was a pioneer in the development of wireless telegraphy and television.
Armstrong worked hard and thoroughly to find out how the tube worked and devised a circuit, called the regenerative circuit, also known as feedback circuit. In 1912, that circuit was able to bring in signals with a thousandfold amplification, loud enough to be heard across a room. Armstrong also discovered that at its highest amplification the tube’s circuit shifted from being a receiver to being an oscillator, or primary generator, of wireless waves.
The regenerative circuit, as a radio wave generator, is at the heart of all radio-television broadcasting today. As a result, Edwin Howard Armstrong is amongst the most important names in the history of FM radio.
However, there was a series of corporate patent suits by De Forest that challenged Armstrong’s priority. This went on for more than 14 years, and was argued twice before the U.S. Supreme Court, before it finally ended in favour of De Forest because of a judicial misunderstanding of the nature of the invention. However, this verdict was never accepted by the scientific community. The Institute of Radio Engineers refused to officially cancel an earlier gold-medal awarded to Armstrong for the discovery of the regenerative circuit and he later also received the Franklin Medal, highest of the United States’ scientific honours. This reaffirmed Armstrong’s invention of the regenerative circuit.
This new invention that opened the age of electronics played a huge role in Armstrong’s life. It led him to become an instructor at Columbia University and also led him to the U.S. Army Signal Corps laboratories in World War I in Paris. Here Armstrong invented the superheterodyne circuit, which can receive, convert, and greatly amplify very weak, high-frequency electromagnetic waves. This technology underlies more than 95% of all radio, radar, and television reception over the airways in today’s world.
It also led Armstrong into early association with David Sarnoff, the man destined to lead the postwar Radio Corporation of America (RCA), whose young secretary Armstrong later married. After the war, Armstrong returned to Columbia University to become assistant to a notable physicist and inventor and also his revered teacher, Michael Pupin.
Armstrong sold patent rights on his circuits for large sums in cash and stock to major corporations, including RCA. In the radio boom of the 1920s, Armstrong found himself a millionaire. He continued teaching at Columbia and financed his own research, working along with Michael Pupin on the long-unsolved problem of eliminating static from radio. He later inherited Pupin’s professorship.
FM Broadcasting
Armstrong secured four patents on advanced circuits in 1933 and revealed an entirely new radio system, from transmitter to receiver. The new system modulated, or varied, the wave’s frequency, or the number of waves per second, over a wide band of frequencies instead of varying the amplitude, or power, of radio waves to carry voice or music, as in all radio before then. This created a carrier wave where that natural static, which was created by electrical storms, could not enter into. Wide frequency range of Frequency Modulation, commonly known as FM, resulted in the first clear, practical method of high-fidelity broadcasting.
However, the radio industry was not willing to embrace the new system as it required a basic change in transmitters and receivers. In 1939, Armstrong himself had to build the first full-scale FM station to prove its worth and that cost him more than $300,000. Armstrong then had to develop, promote, sustain the system (also through World War II when he again turned to military research), and fight off postwar regulatory attempts to limit FM’s growth.
While FM did slowly establish itself, Armstrong found himself entrapped in another seemingly endless patent suit to retain his invention. With most of his wealth gone in the battle for FM, Armstrong, ill and aging, took his own life in 1954.
Over time, there has been increased recognition of Armstrong’s place in science and invention and FM is now the preferred system in radio, the required sound channel in all television, and the dominant medium in microwave relay, mobile radio, and space-satellite communications. After his death, Armstrong was elected to the pantheon of electrical greats by the International Telecommunications Union, and joined figures like Alexander Graham Bell, André-Marie Ampère, Guglielmo Marconi and Michael Faraday.