Sinclair Executive

The Executive was launched in September 1972 at the price of £79.95 plus VAT, equivalent to £1,120 in 2021 when adjusted for inflation. This was around half the price of comparable calculators, but still twice the average weekly wage.[3][4][5] It was the first pocket calculator, and the first to be mass-produced, and its introduction to the market coincided with a number of other companies entering the calculator market.[5][6]

Clive Sinclair, reckoning that the market for "executive toys" was not especially sensitive to price, ordered components for 100,000 calculators.[7] The Executive was highly successful, and made 1.8 million pounds profit for Sinclair Radionics.[8] It was well received by both domestic and foreign markets, and US$1.5 million worth of Executives were sold in Japan in early 1974 at six times the price of Japanese models.[9] The parts, consisting of the TMS1802 chip, 22 transistors, 50 resistors and 17 capacitors, cost close to £10, compared with a sale price of close to £80.[10] The Executive impressed the engineers at Texas Instruments, who had used the same chip to produce a longer and wider calculator that was over three times as thick and a great deal more expensive.[10] In 1974, sales of the Executive were greater than £2.5 million, and Sinclair was producing 100,000 calculators each month, of which 55% were exported.[11]

A Sinclair Executive purchased by a Russian diplomat exploded in his breast pocket, allegedly leading to an official Soviet investigation.[12] It was found that it had been left on by accident, leading to a current drain on the batteries that overheated them until they burst.[13]

It was significantly smaller than any of its competitors, and the first calculator that could easily be carried in a pocket.[3][1] According to a Sinclair executive quoted in the Financial Times, "one must always bear a packet of cigarettes in mind as the ideal size," possibly a quip on Clive Sinclair's smoking habit.[10] The Executive weighed 2.5 ounces (71 g) and measured 56 by 138 by 9 millimetres (2.20 in × 5.43 in × 0.35 in).[1] The case, designed by Iain Sinclair,[14] was made of black injection-moulded polycarbonate and required flexible glue to hold the two halves together.[10]

Design Magazine described it as "at once a conversation piece, a rich man's plaything and a functional business machine".[12][15] One Executive is on display at the Museum of Modern Art in New York City, and the futuristic design earned it the Design Council Award for Electronics in 1973.[8][16] It was the first calculator designed for aesthetic appeal, and New Scientist described it as "not so much a professional calculator - more a piece of personal jewellery".[10]

The Executive Memory was launched in November 1973, with the same dimensions as the original, but with the ability to memorise subtotals from any number of chain calculations.[20][21][19] There were at least three versions, including the black and white Type 1, and the Type 2 with a gold keyboard.[20][21] The Executive Memory sold at the lower price of £24.95.[8]

• Dale, Rodney (1985). The Sinclair Story. Duckworth. ISBN 9780715619018.
• Cockshott, Paul; Mackenzie, Lewis; Michaelson, Gregory (2012). Computation and its Limits. Oxford University Press. ISBN 9780191627491.