Clive Sinclair 1985 owing to Sinclair's financial troubles.) The following year, he received a knighthood and formed Sinclair Vehicles Ltd. to develop electric vehicles, which resulted in the unsuccessful Sinclair C5 in 1985. In 1984, Sinclair launched the Sinclair QL computer, intended for professional users. Development of the ZX Spectrum continued with the enhanced ZX Spectrum 128 in 1985. In April 1986, Sinclair Research sold the Sinclair trademark and computer business to Amstrad for £5 million. Sinclair Research Ltd. was reduced to an R&D business and holding company, with shareholdings in several spin-off companies, formed to exploit technologies developed by the company.
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;