The Black Watch is an electronic wristwatch launched in September 1975 by Sinclair Radionics, costing £17.95 in kit form and £24.95 ready-built. The product was beset by technical problems including a battery life of just 10 days, variable accuracy and a very sensitive integrated circuit which could be rendered useless by a static shock from a nylon shirt. In spite of this, Sinclair’s advertising still claimed:

If that sounds technical, think of the outcome: a watch with no moving parts, a watch with nothing to go wrong, a watch which gives accuracy never achievable by the most precise mechanical engineering.[1]