The Ferrranti Sirius was sold with the basic CPU which could be expanded if necessary to increase the amount of memory. It used nickel acoustic delay line memory in trays. The CPU was the main unit and had 1000 word of store with a word = 40 bits. The system could be expanded with extra memory units with 3000 word store but the maximum configuration was three extra units to give 10,000 word of store. Input and output was via punch tape with a teletype and punch machines. The computer was operated by a small unit set on a desk in front of the CPU. The desk was separate from the CPU but supported by two small metal file cabinets on each side.
It was designed by Ferranti Limited at their West Gorton factory in England and it was developed/manufactured from 1958-1962. It was one of the earliest computers to use transistors rather than valves (vacuum tubes). Thus it was relatively small (small enough to stand behind an office desk), had low power requirements, it ran off a standard 230 volt 13 amp socket and it did not need special air conditioning. A full system consumed about 2kW. It had a decimal display and a facility to slow the processor for demonstration and educational purposes.
ICIANZ purchased a Ferranti Sirius with 7,000 word of store which equates to one CPU and two extra memory units.