IBM 702

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IBM 702 system: From left to right, CRT memory, 702 CPU, 717 printer, operator's console, 757 printer control unit, 752 tape control unit, five 727 tape drives, 732 drum storage, five 727 tape drives, card reader, card punch, and reader/punch control units.

The IBM 702 (photos) was announced September 25, 1953 and withdrawn October 1, 1954, but the first production model was not installed until July 1955. The IBM 705 replaced it.

The system used electrostatic storage, consisting of 14, 28, 42, 56, or 70 Williams tubes with a capacity of 1000 bits each for the main memory, giving a memory of 2,000 to 10,000 characters of 7 bits each (in increments of 2,000 characters), and 14 Williams tubes with a capacity of 512 bits each for the two 512 character accumulators.

A complete system included the following units:

• IBM 702 Central Processing Unit
• IBM 712 Card Reader
• IBM 756 Card Reader Control Unit
• IBM 717 Printer
• IBM 757 Printer Control Unit
• IBM 722 Card Punch
• IBM 758 Card Punch Control Unit
• IBM 727 Magnetic Tape Unit
• IBM 752 Tape Control Unit
• IBM 732 Magnetic Drum Storage Unit

[edit] External links

• IBM Archives: 702 Data Processing System
• IBM 702 Documents on bitsavers
• The Williams Tube