The Berthold Diatronic was introduced in 1967. It was targeted at medium-sized printing companies that needed to produce a wide range of documents without the cost and complexity of high-end digital typesetters (Berthold AG, n.d.). Unlike the earlier and more limited Berthold Diatype, which was largely confined to advertisements and other display type applications, the Diatronic had a real keyboard and could justify text, making it also useful for newspapers and books.

The Diatronic was small, roughly the size of a desk, and was delivered (almost) fully assembled (Berthold AG, n.d.). Text was entered with a typewriter-style keyboard—much faster than the Diatype's hand-operated lever. The entire line of text was stored electronically to allow justification by the built-in computer before the text was set. The operator could see the eight previously typed characters and could make corrections, but only within those eight. Earlier errors had to be corrected later (Deutsches Technikmuseum 2022, 13:20).

Fonts were stored as a grid of characters on a rectangular glass plate. Each grid held 126 characters. The Diatronic produced font sizes from 6 to 20 pt using zoom optics. Eight grids could inserted in the magazine, allowing fonts to be mixed and matched arbitrarily. Switching fonts in the middle of a sentence was accomplished by pushing a button.