A new book about the history of the pocket calculator

[brouhaha]

(05-30-2023 08:20 AM)Paul Dale Wrote:  

(05-29-2023 10:55 PM)Steve Simpkin Wrote:  …, helped build the atomic bomb, …

Interesting, I wonder what model pocket calculator existed in the early - mid 1940s?
Paul

Not pocket, but extensive calculations were performed using electromechanical equipment from IBM. Specifically, the 601 multiplier (some units modified to also provide division), 405 accounting machine (tabulator & printer), 513 reproducing summary punch, 031 alphabetic duplicating keypunch, 075 card sorter, 077 collatot, and probavlyly a few other card processing machines. This went far beyond what was practical to do using slide rules, though slide rules were certainly used for less extreme calculatiions.

This equipment was normally "programmed" by wiring plugboards, and the machines were not normally interconnected. A plugboard could be removed from a machine and replaced by a plugboard wired differently, so that you could have the equivalent of a library of programs for that machine. Los Alamos devised ingenious ways to interconnect the equipment, and to semi-automate data flow over cards from one machine to another, to partially automate many calculations, including some that required iterative solution.

This work probably inspired IBM's Card Programmed Calculator, introduced in 1949, which was also composed largely of a set of machines originally designed to be used separately. This included the 604 _electronic_ multiplier in place of the earlier 601. The CPC was the forerunner of the 650 computer, which was drum-based and was programmable in the modern sense (Von Neumann architecture, programs stored in same memory space as data).