Major Armstrong's Tower (Palisades Interstate Park

Sep / Oct '07

Major Armstrong's Tower

By Lindsey Foschini

Tucked in the woods west of bustling Route 9W in Alpine is the Armstrong Tower, a three-armed steel structure rising 425 feet into the sky. While the tower is a prominently visible landmark within an area encompassing hundreds of square miles—in New York, New Jersey, and Connecticut—few who see it are aware of the story behind the tower or the man who built it.

Edwin Armstrong was born in New York City in 1890. When he was twelve years old, his family moved to Yonkers. Throughout his childhood, Armstrong, who read up on inventions and experimented with radios, sought to make improvements on the quality of sound transmitted by radio signal. As a junior at Columbia University, Armstrong achieved this goal in part when he invented the regenerative-oscillating circuit, an innovation that helped pave the way for transatlantic radio telegraphy.

Not long after this discovery, Lee DeForest, another inventor, claimed that he was the first inventor of the regenerative-oscillating circuit. The issue was brought before the Supreme Court, which ruled in DeForest’s favor. Although Armstrong officially lost claim to this invention, the scientific community continued to credit him for the invention and he received a gold medal from the Institute of Radio.

After graduating in 1913, Armstrong taught at Columbia and later entered the Army Signal Corps, where he became a Major and invented the superheterodyne circuit, which further improved the sound carried by radio transmission. Armstrong’s development led him into employment for his friend David Sarnoff, who was the head of RCA and founder of NBC. (Sarnoff’s secretary, Marion MacInnis, would become Armstrong’s wife.)

Then, in 1933, after securing four patents, Armstrong was responsible for one of the most important discoveries in the development of radio: the invention of FM (frequency modulation) broadcasting. Unlike AM (amplitude modulation) broadcasting, which varies the power of waves in order to transmit sound, FM varies the number of waves per second over multiple frequencies. Because of this, FM is clearer, less distorted, and can carry the sounds of music and the human voice with more fidelity than AM. In 1941, the FCC declared FM the audio standard for broadcasting.

Still, FM did not immediately take off. The new system would require the radio industry to replace its hardware and start over, which would mean major adaptations—and expenses. After years of allowing Armstrong to experiment atop the Empire State Building, RCA requested his resignation in 1937, stating that they wished explore the development of TV. In addition to this, RCA refused to pay royalties to Armstrong for use of his patents. Despite this turn of events, Armstrong’s determination to prove the value of FM only increased.

In 1938, Armstrong turned to the woods of Alpine, where he built his own transmission station and tower, spending over $300,000 of his own money. The Armstrong tower, as it came to be known, as tall as the cliffs on which it stands, was built on land that had been visible to Armstrong from his childhood home. This was a prime location for a radio tower, as it had unobstructed air space for as far as the eye could see.

While Armstrong was running the first FM radio station, manufacturers were infringing upon his patents by building and selling FM equipment. Reminded of what he still perceived as the loss of his credit to DeForest for the invention of the regenerative-oscillating circuit years before, Armstrong took up the battle, eventually engaging in twenty-one patent-infringement lawsuits. He devoted all of his resources, emotionally as well as financially, to this struggle. Although his tower stood strong, Armstrong could not. In 1954, at the age of 64, despondent over his ongoing legal troubles, he penned a farewell letter to his beloved wife and stepped out the thirteenth-floor window of his apartment in New York City.

After her husband’s death, Marion Armstrong continued to fight the patent lawsuits. At the end of thirteen years and after defeating companies such as RCA and Motorola, Mrs. Armstrong had won all twenty-one of her husband’s lawsuits. Edwin Armstrong was permanently established as the inventor of FM.

Although the tower was turned off on March 31, 1954, it did not stay silent. While it was used for several purposes, the tower’s greatest contribution came in 2001. On September 11, with the loss of the World Trade Center, local television stations lost their transmitters. With a need for an alternative transmission location, they turned to the Armstrong Tower. The tower carried TV signals for several stations, including WNBC, the descendant of RCA’s experimental TV station responsible for the loss of Armstrong’s job.

Edwin Armstrong said of his invention of FM and its gradual popularity, “If you build a better mousetrap, the world doesn’t necessarily beat a path to your door.” Regardless of having made incredible accomplishments, this was true for Armstrong, who, along with his achievements, often goes unrecognized. Yet despite the anonymity that Armstrong endured both during and after his life, one hopes he would find great satisfaction in knowing that his tower, reaching high into the New Jersey sky, still serves.

This article was based primarily on “The Father of FM—the Tragic Story of Major E.H. Armstrong” by Jeanne Hammond in the Spring 1994 issue of The Yonkers Historical Society Newsletter.

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