40.1 MB (1.8 MB compressed)
4794 x 2923 pixels
40.6 x 24.6 cm ⏐ 16.0 x 9.7 in (300dpi)
EMILIO SEGRE VISUAL ARCHIVES / AMERICAN INSTITUTE OF PHYSICS / SCIENCE PHOTO LIBRARY EMILIO SEGRE VISUAL ARCHIVES / AMERICAN INSTITUTE OF PHYSICS / SCIENCE PHOTO LIBRARY
Editorial use only.
Vacuum tubes. These vacuum tube, or thermionic valve, diodes were invented by John Ambrose Fleming in 1904. He used the diodes to rectify high-frequency oscillations in radio equipment, allowing weak signals to be detected. Photograph from 'The Thermiotic Valve and its Developments in Radio-Telegraphy and Telephony,' by John Ambrose Fleming, 1924. Restrictions:.
Model release not required. Property release not required.