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Lee De Forest
Lee De Forest was born Aug. 26, 1873, Council Bluffs, Iowa. De Forest was the son of a Congregational minister. His father moved the family to Alabama and there assumed the presidency of the nearly bankrupt Talladega College for Negroes. Excluded by citizens of the white community who resented his father’s efforts to educate blacks, Lee and his brother and sister made friends from among the black children of the town and spent a happy although sternly disciplined childhood in this rural community. (Kraeuter, 74). As a child he was fascinated with machinery and was often excited when hearing of the many technological advances during the late 19th century. He began tinkering and inventing things even in high school, often trying to build things that he could sell for money. By the age of 13 he was an enthusiastic inventor of mechanical gadgets such as a miniature blast furnace and locomotive, and a working silverplating apparatus. (A Science Odyssey: People and Discoveries).
His father had planned for him to follow him in a career in the clergy, but Lee wanted to go to school for science and, in 1893, enrolled at the Sheffield Scientific School of Yale University, one of the few institutions in the United States then offering a first-class scientific education. (Kraeuter, 74). De Forest went on to earn the Ph.D. in physics in 1899, with the help of scholarships, and money his parents made by working odd jobs. By this time he had become interested in electricity, particularly the study of electromagnetic wave propagation, then being pioneered chiefly by the German Heinrich Rudolf Hertz and the Italian Guglielmo Marconi. De Forest’s doctoral dissertation on the “Reflection of Hertzian Waves from the Ends of Parallel Wires” is said to possibly be the first doctoral thesis in the United States on the subject that was later to become known as radio. (Kraeuter, 76).
His first job was with the Western Electric Company in
Chicago, where, he began working in the dynamo department, then working his way up to the telephone section and then to the experimental laboratory. While working after-hours on his own, he developed an electrolytic detector of Hertzian waves. (A Science Odyssey: People and Discoveries, 1999). The device was very successful, as was an alternating-current transmitter that he designed. In 1902 he and his financial backers founded the De Forest Wireless Telegraph Company. In 1902, De Forest began giving public demonstrations of wireless telegraphy for businessmen, the press, and the military in an effort to inform and expand its succcess.
De Forest invented the Audion, or triode, device in 1906, by inserting a grid into the center of a vacuum tube. Applying voltage to the grid controlled the amount of a second current flowing across the tube. a vacuum tube device that could take a weak electrical signal and amplify it into a larger one. (A Science Odyssey: People and Discoveries, 1999). In 1913, AT&T installed audions to boost voice signals as they crossed the US continent. Soon the audion was being used in radios as well. In 1921, De Forest invented a way of recording sound on movies. He started a company, the De Forest Phonofilm Corporation, but he couldn’t convince the film industry to try using sound. Eventually, film makers finally came around several years later, but the Phonofilm Company had folded, so they decided to use an entirely different method. (Kraeuter, 77). (Though some time later movies actually began to use the method De Forest originally proposed.)
Lee De Forest was a pioneer in the development of wireless telegraphy, sound pictures, and television. His triode made practicable transcontinental telephony, both wire and wireless, and led to the foundation of the radio industry. He is frequently called “the father of radio.” (Kraeuter, 75). The first high-powered naval radio stations were designed and installed by him Lee De Forest invented the audion. The audion, or triode, at the heart of the vacuum tube is what the transistor was built to replace. The audion helped AT&T set up coast-to-coast phone service, and it was also used in everything from radios to televisions to the first computers. (A Science Odyssey: People and Discoveries, 1999). By the time he died he had over 300 patents, but few of them ever had much success. In fact, De Forest seemed to have a long streak of failures. He was regularly involved in patent lawsuits (indeed, he spent his fortune on legal bills). He went through four marriages, had a number of failed companies, was defrauded by his business partners, and was even once indicted (but later acquitted) for mail fraud. (Kraeuter, 79).
With the audion, however, De Forest had a solid success. De Forest has been labeled one of the fathers of the “electronic age,” since the audion helped start the explosion of electronics earlier this century. American inventor of the Audion vacuum tube, which made live radio broadcasting possible and became the key component of all radio, telephone radar, television, and computer systems before the invention of the transistor in 1947. (Kraeuter, 79). Forest passed away on June 30, 1961 in Hollywood, CA. De Forest wrote an autobiography entitled Father of Radio, but did not get that recognition from the rest of the world. He is remembered as one contributor to an industry that was, truth, the work of many people. (Kraeuter, 79).
Kraeuter, David W. (1992). Radio and Television Pioneers.
New Jersey: The Scarecrow Press, Inc.
A Science Odyssey: People and Discoveries. (1999) [Online].
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