Sinclair Research "FM Wristwatch Radio", an LCD wristwatch with a radio attached. However, the watch had several problems and never went into full production. Sinclair had long had an interest in electric vehicles, and during the early 1980s he worked on the design of a single-seater "personal vehicle", eventually starting a company called Sinclair Vehicles Ltd in March 1983. He launched the Sinclair C5 electric vehicle on 10 January 1985, but it was a commercial disaster, selling only 17,000 units and losing Sinclair £7,000,000. Sinclair Vehicles went into liquidation later the same year. The failure of the C5, combined with those of
Clive Sinclair 1,000 a month, placing orders with suppliers for 10,000 of each component to be delivered. Sinclair wrote a book for Bernard's Publishing, "Practical transistor receivers Book 1", which appeared in January 1959. It was re-printed late that year and nine times subsequently. His practical stereo handbook was published in June 1959 and reprinted seven times over 14 years. The last book Sinclair wrote as an employee of Bernard's was "Modern Transistor Circuits for Beginners", published in May 1962. At Bernard Babani he produced 13 constructors' books. In 1961 Sinclair registered Sinclair Radionics Ltd. His original choice, "Sinclair Electronics", was taken;