---
title: CSIRAC
categories:
- Computers
types:
- Professional Computer
origins:
- Australia
years:
- '1949'
params:
  name: CSIRAC
  image: /media/museum/photos/csirac_system_s1.jpg
  company: /companies/csirac
  company_name: CSIRAC
  specs:
  - label: NAME
    value: CSIRAC
  - label: MANUFACTURER
    value: CSIRAC
  - label: TYPE
    value: Professional Computer
  - label: ORIGIN
    value: Australia
  - label: YEAR
    value: '1949'
  - label: BUILT IN LANGUAGE
    value: Machine code
  - label: KEYBOARD
    value: Switch panel
  - label: CPU
    value: No CPU, 2000 vacuum-tubes
  - label: SPEED
    value: About 500 instructions per second, later raised to 1000 i/s
  - label: RAM
    value: 768 x 20-bit words stored in mercury delay lines
  - label: TEXT MODES
    value: 16 columns x 20 lines display
  - label: SOUND
    value: Built-in speaker able to play primitive music
  - label: SIZE / WEIGHT
    value: several tons
  - label: BUILT IN MEDIA
    value: 1024-word drum disk, Teletype
  tabs:
  - emulators
  emulators:
  - title: CSIRAC Emulator
    url: http://www.csse.unimelb.edu.au/dept/about/csirac/emulator.html
    platform: Windows
    text: ''
  comments:
  - author: Erik N (Australia)
    date: Thursday 22nd September 2011
    text: I remember first seeing this computer in the Melbourne Museum when I was only 3 - and I can remember all the lights flickering although it wasn''t turned on. If it had been, the Melbourne Museum''s circuit breakers would have all tripped.
  - author: JBH (Australia)
    date: Monday 13rd September 2010
    text: |-
      Not so funny-one of the programmers who worked on it has developed an emulator!

      http://www.csse.unimelb.edu.au/dept/about/csirac/emulator.html

      It was also the first computer used to play music, believe it or not....
  - author: Sam (UK)
    date: Thursday 5th May 2005
    text: Well, it might be interesting.
  - author: Emuman (European union)
    date: Friday 22nd April 2005
    text: What about emulator of this computer ? huh hah hah
  oc_id: 1085
  source:
    url: https://web.archive.org/web/20230605042525/http://www.old-computers.com/museum/computer.asp?c=1085
    date: '2023-06-05'
---

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 \[known as CSIRO\* today\], to design and build the **first Australian electronic computer**.

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 paralleled, 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. It was in Melbourne that CSIRAC came into its own 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 donated it to the Museum of Victoria. It is now at the Melbourne Museum, and was modified to blink its lights on and off for the exhibition, although it isn't actually turned on.

Information taken from the [detailed page](http://www.cs.mu.oz.au/csirac/) of the University of Melbourne dedicated to the CSIRAC computer.

<table> <tr> <td></td> <td>We need more info about this computer ! If you designed, used, or have more info about this system, please send us pictures or anything you might find useful.</td> <td></td> </tr> </table>