ICT Type 550/2 Electronic Calculator

ICT Type 550/2 Electronic Calculator and Type 239/2 Gang punch
Field Engineering Manual TLS-001-1

The Type 550/2 Electronic Calculator is a major item in the range of 80-column Data Processing Equipment. It can be programmed to carry out a wide range of calculations incorporating addition, subtraction, multiplication and division.
The Two Units
The electronic calculator is composed of two units, the gang punch (Type 239/2) and the calculating unit.

(a) The gang punch provides the input and output facilities for the equipment. Information to be processed is read from punched cards and transferrec?to the calculator. The results of processing are punched either into the same cards or into specially desig- nated cards atthe punching station of theType239/2 Gang Punch.

(b) The calculating unit converts, stores and processes the informa- tion read by the input and passes the results back for recording in punched card form.
Data is processed according to instructions drawn from control panels which are quickly interchangeable. The program of processing is determined by plug wires inserted into these panels by the operator.

Operations are carried out, within the program capacity of the madhine, at a speed of 6,000 card passages an hour, regardless of the complexity of the calculations. 50 program steps (200 primary cycles) are available for each card.

kindly donated by Julia Haylett on behalf of her husband Albert John Haylett who worked for ICT

Reference Number :

Date Published : 1964

Manufacturer : ICT

Platform : 550/2






This exhibit has a reference ID of CH10778. Please quote this reference ID in any communication with the Centre for Computing History.

ICT Type 550/2 Electronic Calculator

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