Summary

I.C.L. 1004 plug board with display plaque. Made in the 1960s by Univac (or to be correct, the Univac Division of Sperry Rand, headed by General Douglas MacArthur.
Used by the administrative and data processing staff of the University of Melbourne 1965-1972.

Univac tried to buy ICL, but the British Government re-financed ICL, and thus blocked the takeover. The 1004 system had nothing to do with ICL/ICT, so the plug-board is from .
The "ST 043414 Plug-board" used in the Univac 1004, which was a "Hybrid" computer in the sense that it used a plug-board along with punched cards.
The UNIVAC 1004 was a transistorised plug-board programmed punched card data processing system, introduced in 1962. Total memory was 961 characters (6 bits) of core memory. Peripherals were a card reader (400 cards/minute), a card punch (200 cards/minute) using proprietary 90-column, round-hole cards, or IBM-compatible 80-column cards, a drum printer (400 lines/minute) and a Uniservo tape drive.

Each plug-board represented a computer program. There were specific areas on the plug-board for input and output functions and for memory. These areas were connected by wires inserted by the programmer. If the plug-boards were so heavily wired (several centimetres thick with wires), it was difficult to see the wire sockets. Total memory of the 1004 was 1024 bytes; in 1995, when this item was acquired by the Museum, personal computers have a minimum of 4 megabytes, i.e. over 4,000 times larger.

A plug-board program called "Emulator" was widely installed to convert 1004s to stored-program operation, reading in instructions from program decks of cards which determined the processing of the following data decks. Once installed, "Emulator" was rarely removed as it could run the machine as desired and, as almost every machine function was used, it was physically heavy from the sheer mass of installed jumpers filling nearly the entire board. Emulator was not a Univac product, rather it was built by each customer, a tedious task.
The "CPU" required 30 sq ft of floor space, 3000 watts of power, weighed 2500 lbs., and cost $46000.
The Univac 1004 is not considered by some to be a true computer, as the "program" was mostly configured on the plug-board, and thus was not a "stored program system".

Physical Description

Metal frame panel with matric of holes. Hundreds of interconnecting wires plugged into the holes represent the program. Handles on sides to facilitate loading into machine. Plaque marked "CONTEMPORARY ARTIFACT - CONSULTANT-WIRED PLUG BOARDS FOR THE ICL 1004 SYSTEM. THIS BOARD OPERATED FOR PAYROLL CONSOLIDATION 1965-72". Each plugboard represented a computer program. There were specific areas on the plugboard for input and output functions and for memory. These areas were connected by wires inserted by the programmer. After the plugboards were so heavily wired (several centimetres thick with wires), it was difficult to see the wire sockets. Total memory of the ICL 1004 was 1024 bytes.

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