Who was Lee de Forest? Everything You Need to Know

Quick Facts

Died At Age: 87

Family:

father: Henry Swift de Forest

mother: Anna Robbins

Died on: June 30, 1961

U.S. State: Iowa

discoveries/inventions: Invented The Audion, The First Triode Vacuum Tube And The First Electrical Device Which Could Amplify A Weak Electrical Signal And Make It Stronger.

More Facts

awards: IRE Medal of Honor (1922)
Edison Medal (1946)

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Childhood & Early Life

He was born as the son of Henry Swift de Forest and Anna Robbins. His father was a Congregational Church minister and the President of Talladega College.

From a young age he was fascinated by machinery and followed the developments taking place in the technological world. An intelligent and creative boy, he was hardly into his teens when he started designing and developing new machinery.

His father had hoped that he would follow in his footsteps and pursue a career in clergy but the young boy had plans to study science. He went to Mount Hermon School before enrolling at the Sheffield Scientific School at Yale University in Connecticut in 1893.

He received his bachelor’s degree in 1896 and went on to earn a Ph.D in physics in 1899. His dissertation “Reflection of Hertzian Waves from the Ends of Parallel Wires” was on radio waves which he had completed under the guidance of the theoretical physicist Willard Gibbs.

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Career

He was employed at the Western Electric Company in Chicago. Initially he was in the dynamo department though he eventually also began to devise telephone equipment. During this time he also began to conduct his own experiments during his leisure time and developed an electrolytic detector of Hertzian waves.

In 1902, he founded his own business, the De Forest Wireless Telegraph Company which sold radio equipment that he had developed. He had hoped to make profits on his inventions by starting his own company but he was cheated by his own business partners and the company became insolvent by 1906.

He developed an electronic amplifying vacuum tube, the Audion, in 1906. It was the first electronic device that could amplify a weak sound into a stronger signal. At that time however he had no idea about the potential his great invention held.

He designed a diode vacuum tube detector, a two-electrode device which was a variant of the Fleming valve which had been invented two years earlier. He then developed a three-electrode device which was a better detector of electromagnetic waves. This invention was granted a patent in 1908.

After the failure of his first company he started another company called the De Forest Radio Telephone Company. By 1909 this company too began to fail, again because of his cheating partners. He was even indicted in 1912 but was later acquitted of the charges.

In 1916, he broadcasted the first radio advertisements for his own products from the experimental radio station 2XG in New York City. The Presidential election report for Charles Evans Hughes and Woodrow Wilson was also broadcast by him.

He developed a sound-on film technique for which he filed a patent in 1919. It was called the De Forest Phonofilm process. Over the next few years he studied the other sound film systems and established his De Forest Phonofilm Company in 1922 and demonstrated Phonofilm to the press in 1923.

The Phonofilm process synchronized sound directly onto film and was used to record stage performances, speeches and music concerts. By the late 1920s Hollywood too began to use sound-on film systems.

Major Works

His invention Audion which was the first ever triode vacuum tube for amplifying high-frequency radio signals heralded in the era of electronic communication. This was the invention which made many further developments in the field possible thus earning his the title ‘Father of Radio’.

Awards & Achievements

In 1922, he was awarded the IRE Medal of Honor as "recognition for his invention of the three-electrode amplifier and his other contributions to radio”.

He received the Edison Medal of the American Institute of Electrical Engineers 'For the profound technical and social consequences of the grid-controlled vacuum tube which he had introduced' in 1946.

Personal Life & Legacy

He married four times. His first marriage was to Lucille Sheardown in February 1906 which ended after just a few months. He tied the knot for the second time with Nora Stanton Barney in 1907. This marriage produced a daughter and ended in 1911.

In December 1912 he married Mary Mayo and had one daughter with her. The couple divorced in 1930.

His fourth and last marriage was to Marie Mosquini in 1930. This marriage lasted till De Forest’s death.

He died in 1961 at the age of 87. In spite of all his achievements he could never enjoy financial success and died a poor man.

Lee de Forest Biography