Only a brass plaque on a tombstone-size rock now marks 913 Emerson Street, where events in 1912
changed the world profoundly and forever. Here, radio pioneer Lee De Forest, working for the
Federal Telephone Company, coaxed the Audion (triode) vacuum tube that he had invented earlier to amplify electrical signals, and electronics
The building blocks of our Silicon-Information Age -- oscillators for generating radio,
TV, and computer signals; the amplifiers and electronic switches that make them useful -- are variations of the amplifier Dr. De Forest
invented at 913 Emerson, Palo Alto, California. The communications and information revolution these devices enabled is rivaled in its impact
only by the invention of writing and the printing press.
* For his groundbreaking
work in Palo Alto, De Forest created a correspondingly
pioneering electrical measurement unit, The Block. He rated the performance of his amplifier circuits
in terms of the number of city blocks from this laboratory from which he could hear their emissions. Homer Avenue
was at the one-block mark, a milestone. One literally walks in history here.
(The Block is no
longer used by electronics professionals, but stereo owners often experiment with it.)
Photo: Palo Alto Historical Association
De Forest's laboratory was located in this modest house, which was demolished in 1965 to make
way for a vacant lot. The office building currently occupying its site was built many years later.