Accession No


Brief Description

Hewlett Packard HP-65 electronic pocket calculator, 1974, in case with pack of program cards and quick reference guide.




Hewlett Packard


calculating; computer technology

Earliest Date

Jan. 1, 1974

Latest Date

Dec. 31, 1977

Inscription Date


Plastic; card; leather


Length 161mm; width 92mm; thickness 55mm (in case)

Special Collection

Francis Hookham Collection of Hand Held Electronic Calculators


Donated by Francis Hookham in 1987. Donated to Francis Hookham on 30/09/1981 by individual from Cambridge University Examination Syndicate.


[Hewlett Packard logo] “HEWLETT.PACKARD 65” (front of calculator, bottom)
[Hewlett Packard logo] (front of case)

Description Notes

Brown Hewlett Packard 65, in black leather case which also contains a pack of program cards and a quick reference guide. Calculator has white number keys, and pale grey, blue, yellow and black function keys. A black on/off switch and a black switch for changing between ‘progam’ and ‘run’ mode are at front, top.

Each key has its primary function inscribed on surface, an ‘f’ function inscribed in yellow on the key panel above them, and a ‘g’ function inscribed in blue on the front-side of the key, which is tall and wedge-shaped, and thus readily readable. This way of using the keys was unique to HP.

Red LED display.

Keys are short-travel, quite light to the touch, make a solid, bright click upon depression, and bounce back well (S Davis 4/7/2007).

Rear panel of calculator gives ‘User aids’. Panel inside battery cover gives battery details. Stickers with Francis Hookham’s address on rear and on pack of program cards. Program card pack - ‘Standard Pac’ - contains only 28 cards, not 40 as stated on cover, in four slots in a see-through plastic pack. Quick reference guide is spiral bound flip-top with sections on ‘Procedures’, ‘Key Dictionary’ and ‘Index’. It contains the copyright date 1974 and is numbered 227, not 227A. Case has three slots, for the cards, guide and calculator, with a velcro fastening. It also has a belt clip on the rear.

Good condition.

28 cards



The pocket electronic calculator is now familiar to us all. However, these everyday objects were still a novelty in the early 1970s and priced out of the reach of most customers. To our modern eyes, the operation of a calculator is quite simple, at least for basic arithmetic. We just push the buttons and the machine does the hard part for us. Since calculators never make mistakes, we need never worry about what goes on inside.

Behind the buttons and screen lies a complex set of miniature circuits. It is the ability of electronics firms to make smaller and smaller components that has led to the success of the calculator. All the electronic circuits that provide the calculating power can now fit onto tiny ‘chips’ of silicon. By also developing the technology for liquid crystal displays (LCD’s), manufacturers were able to shrink calculators even further. When solar power arrived towards the end of the 1970s they could even be made without batteries. Prices fell whilst popularity soared.

Despite all this technology, successful use of the calculator still relies on the knowledge of the operator. The latest machines pack in countless functions and require a large instruction manual. Their increasing power has led to debates about their proper use in schools. The widespread use of calculators – at school, home and in the office – has been blamed for falling standards of arithmetic.

This is in contrast with the early days of calculator use. During the 1970s, a number of textbooks were published to encourage people to use what was still an unfamiliar instrument. These would give examples of how calculators could help with anything, from income tax forms to the weekly shopping list!


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