CSIRAC: Our First Computer

In 1947, Maston Beard and Trevor Pearcey led a research group at the Sydney-based Radiophysics Laboratory of the Council for Scientific and Industrial Research (now known as CSIRO), to design and build an electronic computer.

Trevor Pearcey pictured operating CSIRAC
Trevor Pearcey pictured operating CSIRAC

The resources they had available included the vacuum tube or “valve” technology and the pulse techniques developed for radar systems during World War II. Their developments parallelled, but were to a considerable extent independent of computer developments in Europe and the USA.

The CSIR Mk1 ran its first test programs in late 1949, and it was the fifth electronic stored program computer ever developed. It embodied many features novel at the time and was able to operate more than 1000 times faster than the best mechanical calculators. The machine was officially opened in 1951 and used to solve problems both for the Radiophysics Laboratory and outside organisations. It was decommissioned in 1955 and shipped to Melbourne.

On 14 June 1956 the Mk1 was recommissioned and renamed CSIRAC and the new Computation Laboratory at the University of Melbourne was officially opened. CSIRAC was available as a general computing workhorse — from June 1956 to June 1964 over 700 computing projects were processed.

In November 1964, Dr Frank Hirst switched CSIRAC off for the last time and it was donated to the Museum of Victoria.


The CSIRAC pages were originally authored by Steven Pass, then substantially revised and maintained by David Hornsby. Further extracts are taken from The Last of the First, CSIRAC: Australia’s First Computer [PDF], Doug McCann and Peter Thorne, , ISBN 0 7 7340 2024 4. Used with kind permission.

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