Historical Marker · No. 836
Electronics Research Laboratory
Palo Alto, Santa Clara County · California
Erected by the State Department of Parks and Recreation in cooperation with the City of Palo Alto and the Palo Alto Historical Association, 1970
The bronze counts de Forest's two assistants without naming them: Herbert Van Etten, a telephone engineer, and Charles Logwood. The feedback circuit behind the oscillator claim first shows up in a Van Etten notebook entry of August 6, 1912, and it became evidence in de Forest's long patent fight with Edwin Armstrong. One federal court doubted de Forest had understood that accidental arrangement; the Supreme Court sided with him in 1934. De Forest sold partial amplifier rights to AT&T for long-distance calls. Nothing of the laboratory stands at this corner.
What the plaque says
Electronics Research Laboratory Original site of the laboratory and factory of Federal Telegraph Company, founded in 1909 by Cyril F. Elwell. Here, with two assistants, Dr. Lee de Forest, inventor of the three-element radio vacuum tube, devised in 1911-13 the first vacuum tube amplifier and oscillator. World-wide developments based on this research led to modern radio communication, television, and the electronics age. California Registered Historical Landmark No. 836 Plaque placed by the State Department of Parks and Recreation in cooperation with the City of Palo Alto and the Palo Alto Historical Association, May 2, 1970
Where it stands
37.44156, -122.15772 · Directions
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