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Unisonic 21

Unisonic 21

The Unisonic 21 is an arithmetic calculator with 12 digits precision and algebraic logic. It has 4 functions, 25 keys, and a VFD (vacuum fluorescent) display. The power source is 3xC. These are Blackjack games/calculators. The calculator can be switched between calculator and game modes, the latter allowing you to play Blackjack against the machine. In later models the display fascia is designed to suggest a Blackjack table. They have been available in a number of sizes and physical designs over the years. Note: Black-Jack calculator

Facts at a glance:

Display typeVFD
Power Source3xC
Year introduced1975


If you have a Unisonic 21 that is no longer working, you can consider replacing the calculator with a modern equivalent. We suggest the following current models as possible replacements:

See other calculators by Unisonic