The RCA Selectron:
A vacuum tube computer memory from the 1940s

Three Selectron tubes: 4096-bit, 1024-bit, 256-bit Before the personal computer, microprocessor, integrated circuit, or even before transistors there was the Selectron. This electron tube developed at RCA Laboratories in Princeton, New Jersey, could store 4096-bits in one glass envelope. The Selectron was designed at the behest of John von Neumann of the Institute for Advanced Study and intended for use in their digital computer being designed during the 1940s.

These pages -- still undergoing minor development as of 2008 -- will chronicle this amazing, but short-lived, device and the people around it. Please check the updates page for any additions or amplifications.

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