In the course of the 1970s, handheld electronic calculators transformed the way tens of millions of people did arithmetic. Engineers abandoned slide rules, business people gave up desktop calculating ...

Given the dual nature of this product, a DIY electronics kit and a functional desk calculator for electronic hobbyists, it seems only appropriate to review both aspects of it individually.

Interesting Fact: Although the first working copy of the device was ready in 1773, the calculator was not demonstrated until 1778 because of Hahn’s difficulty with the reliability of machine’s ...