Sinclair relocated to Cambridge in 1967.
In the early Seventies he invented the pocket calculator and by 1973 dominated the UK pocket calculator market, having relocated to St Ives the previous year.
New products such as the first digital watch, the Black Watch, and a pocket TV followed but the strain of the development costs led to the breakup of Sinclair Radionics in 1979, principally into Thandar Electronics (instruments) and Sinclair Research (consumer electronics).
In the early 1980s Sinclair refurbished the old mineral water bottling plant at 25 Willis Road (here), mainly for offices. A full-page article in a Sunday newspaper termed the high-tech. building Silicon Alley. He also had Milton Hall as a research centre.
Planet Sinclair is the best place to continue following the history. The Sinclair Museum concentrates on the products.