4 ms·

Fascinating that Willams tube (and Atanasoff–Berry computer's electrostatic drum) is in some way much closer to modern DRAM and flash than ferrites that were so

• adrian_b 2y ago
  John Vincent Atanasoff has written in 1940 a very good report about the design of the Atanasoff-Berry computer (“Computing Machine for the Solution of Large Systems of Linear Algebraic Equations”). In this report, he had analyzed which are the possible solutions for implementing a computer memory. He enumerated 5 kinds of memories: with mechanical bi-stable devices, with electro-mechanical bi-stable devices (e.g. polarized relays), with ferromagnetic materials, SRAM (with vacuum-tube flip-flops) and DRAM (with capacitors). His list covered very well the most important kinds of memories used later. The report “First Draft of a Report on the EDVAC” written by John von Neumann in 1945 added to these alternatives the memories made with delay lines (an idea presumably taken from the discussions with the ENIAC team). Moreover, the von Neumann report has also added a second variant of DRAM besides that using discrete capacitors, i.e. the DRAM made with a charge-storing image tube, like those used at that time for video cameras ("iconoscope memory"). Therefore the idea of the Williams tube has been taken directly from the von Neumann report. It is not known whether this idea has originated from von Neumann himself or whether he had got it from someone else.