Adam’s Vintage Computer Restorations writes about restoring a 1974 Sinclair Scientific calculator.

I recently acquired a Sinclair Scientific calculator from 1974, alongside a large bundle of vintage computers – this was an unexpected (but very welcome) surprise and is in fact my first vintage calculator, though it is basically a pocket computer, so it is certainly in keeping with the rest of my collection.

The Sinclair Scientific pocket calculator was released in 1974 by Sinclair Radionics Ltd, following the release of the world’s first handheld scientific calculator, the HP-35, in 1972. It is a 12-function, pocket-sized scientific calculator which initially retailed at £49.95, dramatically undercutting in price other calculators available at the time. It was based around the Texas Instruments TMS0805 IC, which could only store 320 words and was barely capable of four-function arithmetic – however, by sacrificing some speed and accuracy, Sinclair used clever algorithms to implement full scientific instructions.

Read how this classic calculator was restored in the post here.