calculator.org

the calculator home page

Keystone SC 650

The Keystone SC 650 is an arithmetic calculator with 8 digits precision and algebraic logic. It has 7 functions, 20 keys, and a gas discharge display. The power source is 2xAA.

Facts at a glance:

FeatureValue
TypeArithmetic
Functions7
Keys20
Precision8
LogicAlgebraic
Display typeDischarge
Length140mm
Width81mm
Power Source2xAA
Year introduced1975

Replacements:

If you have a Keystone SC 650 that is no longer working, you can first try replacing the 2xAA 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 Keystone