Invention History: The Father of FM


Not only did FM threaten to topple the established order of AM, but it directly affected Sarnoff by threatening the impending launch of television broadcasting, his baby.

And so, it would happen that 10 days after his FM demonstration, Armstrong would be dismayed when the public was treated to a veritable flood of information about RCA's television, but not a peep about FM. The entire industry, marshaled by Sarnoff, had turned its back on him.

The snub would be the first shot fired in a new war.

Characteristically, Armstrong stuck to his guns. He believed the public would support FM over AM simply because it was better. More specifically, he believed the public would readily support FM over AM if given the opportunity to choose between the two in the marketplace.

Sarnoff asked Armstrong to vacate his FM equipment from the top of the Empire State Building to make room for NBC and its TV broadcasting equipment.

[Sidenote: NBC aired the first experimental TV broadcast in 1938. The network began regular commercial TV broadcasting on July 1, 1941.]

Radio TowerRadio TowerUndaunted, Armstrong made plans to relocate to a new location atop the Palisades near Alpine, New Jersey. Situated 500-feet above sea level, the location was perfectly suited for broadcasting into New York and the surrounding metropolitan area. At the very top he constructed a uniquely shaped, 400-foot-tall antenna.

Appropriately, the location was clearly visible from the room in Yonkers within which Armstrong had brought regeneration to life.

In 1939, the Federal Communications Commission (FCC), after extensive lobbying by RCA and other concerned parties, rejected Armstrong's application for an experimental FM license. The license was issued begrudgingly only after Armstrong threatened to pack up his research and move overseas.

Armstrong's tiny Yankee Network was up and running that year. In 1940, he rejected RCA offer to pay $1 million for his patents because it would not have included royalty payments. Armstrong believed it would be unfair to give RCA a break on royalties while expecting other licensees to pay the fees.

In any event, RCA's offer wasn't on the level because it was studying FM and planning to sell its own receivers based on Armstrong's patents, with or without authorization. Then at the end of 1941, the country was pulled into another shooting war.

During the world war, Armstrong and Sarnoff put their professional differences on hold, while they concentrated on the threat posed by the fascist members of the tripartite pact.

Both contributed their invaluable communications expertise to the government. Armstrong allowed the government to have free use of his FM patents for the duration, Sarnoff would be instrumental in planning communications for the D-Day invasion of Hitler's Fortress Europe.

Hostilities Renewed

The war between Sarnoff and Armstrong began anew right after the Armistice in 1945, when a group of companies headed by RCA petitioned the FCC to change the parameters for FM broadcasting.

The biggest change involved the wholesale shifting of the bandwidth from 44-50 MHz to 88-108MHz, it's current location on the dial. Preventing ionospheric disturbance was the reason given.

Because ionospheric disturbance - an excessive accumulation of plasma in the Ionosphere caused by solar flares - can disrupt telecommunications, the shifting of the frequency bandwidth upward was done "for FM's own good," according to an biographical account of Armstrong by Yannis Tsividis published by Columbia University.

Moving an already established frequency spectrum was bad enough, but the FCC didn't stop there. It reduced the maximum power at which FM station's could broadcast, and prohibited the relaying of signals from central FM broadcasting locations to mountaintop antennas. This imposed additional costs upon small FM broadcasters by forcing them to pay for the privilege of sending programming over AT&T's network of cables.

The impact of the FCC's new mandates was instantaneous. It rendered all existing FM transmitters, receivers, and supporting equipment obsolete.

[Sidenote: It's interesting to note that FM's original bandwidth of 44-50MHz remains vacant.]

Despite the new roadblock, Armstrong remained firm in his resolve to see FM succeed. He worked feverishly to bring everything into compliance with the peevishly revised standards. It would be the final engineering accomplishment of Armstrong's distinguished career.

Meanwhile, RCA had been producing FM radios for years without paying a cent in royalties. And they were not alone. They were joined in their pirating by a host of others including, Sylvania, CBS, and Motorola.

Armstrong had had enough. His patents were set to expire shortly, and it was time to make them pay. In 1948, RCA and NBC were charged with infringement. Armstrong observed at the time, "They will stall this thing until I am dead or broke."

He was right.

RCA's attorneys dragged out pre-trial proceedings interminably, forcing Armstrong to provide details about his taxes, the nature of his agreement with Columbia, and countless other trivialities.

Then in 1949, Sarnoff effectively killed any chance of a settlement when he proclaimed that RCA created FM all by itself without any help from Armstrong.

Meanwhile, Sarnoff's attorneys continued to nitpick.

The seemingly endless niggling had a devastating effect on Armstrong. By 1953, his personal fortune had been consumed by legal fees.

On Thanksgiving evening, his wife, Marion, left him to move in with relatives following a heated argument about, among other things, money. About a month later, Armstrong filed 21 additional patent infringement suits.

Then came the night of January 31, 1954. Armstrong sat at the desk in his 13th floor apartment and composed a two-page letter to Marion. With that task completed, he put on his overcoat, scarf, gloves, and hat. After removing an air conditioning unit from a window, he stepped through the void and fell 10 floors to his death.

A building maintenance worker discovered the body the following day on top of the third floor overhang that broke his fall. The letter to Marion was found where he'd left it.

When informed of Armstrong's suicide, Sarnoff said, "I didn't kill Armstrong." But he was deeply shaken by the death of his one-time friend.

In a biographical account of Sarnoff published by the University of St. Francis, a Catholic Franciscan institution in Joliet, Illinois, author Michael O'Toole said Sarnoff "knew what the litigation was doing to his old friend, but the corporate interests always prevailed."

Apr 15, 2007
by Michelle
Michelle's picture

Mike, Is FM used for


Is FM used for anything else but radio? Is the inventor of FM inventor of FM radio?

Apr 16, 2007
by Mike (not verified)

Yes, EH Armstrong is

Yes, EH Armstrong is considered the inventor of FM. It's used a lot outside of radio. TV  sound is FM. Military, NASA. Cellphones sound technology is based on it. 


Jul 6, 2008
by Anonymous