Sinclair C5 computers like the hugely successful ZX81 and ZX Spectrum, an affordable electric vehicle could unleash pent-up demand for a market that did not previously exist. However, Sinclair performed no market research to ascertain whether there was actually a market for his electric vehicle; as the director of the Primary Contact advertising agency commented in January 1985, the project continued all the way to the prototype stage "purely on the convictions of Sir Clive". With Sinclair's new specifications in hand, Ogle worked on a three-wheeled design dubbed the C5, which bore similarities with the earlier three-wheeled Bond Bug – another Ogle
Sinclair Scientific fraction of the cost of competing calculators. In 1972, Hewlett-Packard launched the HP-35, the world's first handheld scientific calculator. Despite market research suggesting that it was too expensive for there to be any real demand, production went ahead. It cost (about ), but despite the price, over 300,000 were sold in the three and a half years for which it was produced. From 1971 Texas Instruments had been making available the building block for a simple calculator on a single chip and the TMS0803 chipset appeared in a number of Sinclair calculators. Clive Sinclair wanted to design a calculator to