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Hewlett-Packard HP 21 (Woodstock PUMPKIN)

Hewlett-Packard HP 21

The Hewlett-Packard HP 21 is a scientific calculator with 12 digits precision and algebraic logic. It has 25 functions, 30 keys, and an LED (light-emitting diode) display, typical of calculators of this era. The power source is Sealed NiCd battery pack. A sample of this calculator is held in the calculator.org collection.

Facts at a glance:

FeatureValue
TypeScientific
Functions25
Keys30
Precision12
LogicAlgebraic
Display typeLED
Length129mm
Width67mm
Thickness29mm
Weight170g
Power Consumption0.500000W
Power SourceSealed NiCd battery pack
Year introduced1975
Year discontinued1978

Replacements:

If you have a Hewlett-Packard HP 21 that is no longer working, you can consider replacing the calculator with a modern equivalent. We suggest the following current model as a replacement:

See other calculators by Hewlett-Packard