Thursday 12 July 2018

IBM 7070

The IBM 7070 was a mid-range data processing system introduced in 1958. It was IBM's first stored-program computer to use transistors rather than vacuum tubes, the first of a new line of fully transistorised mainframes. The 7070 used around thirty thousand germanium transistors and could perform twenty seven KIPS (thousand instructions per second). The 7070 used machine words consisting of ten digital digits plus a sign. Each digit was encoded by 5-bits. The 7070 used core memory and could store up to around ten thousand words.

Unfortunately the 7070 was incompatible with the models (such as the 705) it was intended to replace. A simulator was needed to run programs written for older computers though the waste of resource and incompatibilities meant the 7070 was a bit of a flop. The later 7080 was said to be fully compatible.

Also coming later were the faster 7072 and 7074 in the early 1960s. They were replaced by the highly successful IBM 360 within a few years.
IBM 7074 (Public domain image)