• 1873 Aug. 26 Born, Council Bluffs, Iowa
• 1896 Ph.B., Yale University, New Haven, Conn.
• 1899 Ph.D., Yale University, New Haven, Conn.
• 1900 Joined Western Electric Co. , Chicago, Ill.
• 1900 Designed alternating current transmitter
• 1900 Developed electrolytic receiver
• 1901 Founded American de Forest Wireless Telegraph Co. (later United Wireless Telegraph Co. )
• 1905 Developed first model of audion amplifier
• 1906 Developed triode vacuum tube
• 1906 Married Lucille Sheardown (divorced 1907)
• 1908 Married Nora Blatch (divorced 1911)
• 1910 Broadcast voice of Enrico Caruso by radio from the Metropolitan Opera House, New York, N.Y.
• 1912 Sold telephone repeater rights to American Telephone and Telegraph Co. , which used his three electrode vacuum tube in first transcontinental telephony
• 1912 Married Mary Mayo (divorced 1930)
• 1913 Demonstrated first oscillating audion tube
• 1913 Became vice president, Radio Telegraph Co.
• 1913 Became vice president, de Forest Radio Co.
• 1916 Made first radio news broadcast
• 1916 Established radio broadcast station
• 1919 Patented phonofilm device for making talking pictures
• ca. 1920 Published How to Set Up an Amateur Radio Receiving Station (New York, N.Y.: de Forest Radio Telephone and Telegraph Co. 32 pp.)
• ca. 1922 Published Wireless in the Home (New York, N.Y.: de Forest Radio Telephone and Telegraph Co. 32 pp.)
• 1923 Demonstrated sound on film at Rivoli Theater , New York, N.Y.
• 1923 Organized de Forest Phonofilm Co.
• 1926 D.Sc., Yale University , New Haven, Conn.
• 1930 Married Marie Mosquini
• 1934 Established Lee de Forest, Inc., Los Angeles, Calif.
• 1942 Published Television, Today and Tomorrow (New York, N.Y.: Dial Press. 361 pp.)
• 1947 Edison Medal of the American Institute of Electrical Engineers
• 1950 Published Father of Radio (Chicago, Ill.: Wilcox and Fallett. 502 pp.)
• 1951 Vice president, National Association for Better Radio and Television
• 1961 June 30 Died, Hollywood, Calif.

...from Lee de Forest Papers, Manuscript Division, Library of Congress, Washington, D.C.