PIONEER ELECTRONICS RESEARCH LABORATORY - View this location on map - This is the original site of the laboratory and factory of Federal Telegraph Company, founded in 1909 by Cyril F. Elwell. Here, Dr. Lee de Forest, inventor of the three-element radio vacuum tube, devised the first vacuum tube amplifier and oscillator in 1911-13. Worldwide developments based on this research led to modern radio communication, television, and the electronics age. Channing Ave and Emerson St, Palo Alto, California Historical

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