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Citizen 820R

The Citizen 820R is an arithmetic calculator with 8 digits precision and algebraic logic. It has 7 functions, 22 keys, and a VFD (vacuum fluorescent) display. The power source is 4xAA.

Facts at a glance:

FeatureValue
TypeArithmetic
Functions7
Keys22
Precision8
LogicAlgebraic
Display typeVFD
Length151mm
Width87mm
Thickness34mm
Power Source4xAA
Year introduced1974
Year discontinued1976

Replacements:

If you have a Citizen 820R that is no longer working, you can first try replacing the 4xAA batteries. If that doesn't solve the problem, then you can consider replacing the calculator with a modern equivalent.

We suggest the following current models as possible replacements:

See other calculators by Citizen