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Lee de Forest (26th August 1873 - 30th June 1961)
1961 Obituary 
We regret to record the death in Hollywood on June 30, at the age of eighty-seven, of Dr. Lee de Forest, pioneer of the radio valve. His invention of the "audio" three-electrode valve, or triode, came in 1906, and was made independently of similar work by Robert von Lieben in Vienna. De Forest was associated with early broadcasting activities in the United States, and between 1919 and 1926 was engaged on development of a system for talking pictures.
His business ventures included the De Forest Radio Telephone and Telegraph Company, and the De Forest Phonofilm Corporation. He held some 300 patents in the United States and other countries, and was a founder, Fellow and past president of the Institute of Radio Engineers.