29:
257:, "one must always bear a packet of cigarettes in mind as the ideal size," possibly a quip on Clive Sinclair's smoking habit. 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). The case, designed by Iain Sinclair, was made of black injection-moulded polycarbonate and required flexible glue to hold the two halves together.
373:
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. There were at least three versions, including the black and white Type 1, and the Type 2 with a gold keyboard. The Executive
344:
of the chips to store information when there is no power, and 1.7 microseconds proved sufficient for the chip to carry out a single change of state of the electronics. Any calculation can be done in 1,000 such changes. This extended battery life to about 20 hours of continuous use with three small
327:
normally consumes 350 milliwatts, but by pulsing the power this requirement was reduced to 20 milliwatts. It was discovered that an early prototype continued to work if the batteries were disconnected and then reapplied quickly enough, as the capacitors in the circuit could hold a charge for up to
233:. 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. In 1974, sales of the Executive were greater than
339:
operating at 200 kilohertz during calculations and dropping to 15 kilohertz between each operation means shut-off time ranges from 3.3 microseconds during calculations to more than 65 microseconds between. The device relies on the
364:
display bought from a
Canadian firm. The small screen reduced the power consumption and material costs, but it was revised several times in pursuit of lower power consumption, creating reliability problems.
240:
A Sinclair
Executive purchased by a Russian diplomat exploded in his breast pocket, allegedly leading to an official Soviet investigation. It was found that it had been left on by accident, leading to a
163:. Introduced in 1972, the calculator was produced in at least two versions with different keyboard markings; a variant called the Sinclair Executive Memory was introduced in 1973.
253:
It was significantly smaller than any of its competitors, and the first calculator that could easily be carried in a pocket. According to a
Sinclair executive quoted in the
479:
453:
202:. This was around half the price of comparable calculators, but still twice the average weekly wage. It was the first pocket calculator, and the first to be
943:
221:
worth of
Executives were sold in Japan in early 1974 at six times the price of Japanese models. The parts, consisting of the TMS1802 chip, 22
213:, ordered components for 100,000 calculators. The Executive was highly successful, and made 1.8 million pounds profit for
936:
457:
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912:
891:
195:
673:
206:, and its introduction to the market coincided with a number of other companies entering the calculator market.
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1021:
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Power is supplied to the chip in 1.7-microsecond pulses as determined by the storage time of a control
210:
299:, and multiply or divide by a fixed constant. The Executive could carry out sums to two, four, or six
993:
756:
521:
405:
711:
263:
described it as "at once a conversation piece, a rich man's plaything and a functional business
174:, reducing the power consumption more than tenfold. The Executive was highly successful, making
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790:
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559:
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described it as "not so much a professional calculator - more a piece of personal jewellery".
279:
Award for
Electronics in 1973. It was the first calculator designed for aesthetic appeal, and
571:
361:
268:
78:
799:. Vol. 4, no. 47. Infoworld Media Group Inc. 29 November 1982. pp. 112–116.
8:
998:
983:
237:, and Sinclair was producing 100,000 calculators each month, of which 55% were exported.
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978:
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Clive
Sinclair, reckoning that the market for "executive toys" was not especially
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56 by 138 by 9 millimetres (2.20 in × 5.43 in × 0.35 in)
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As well as four-function arithmetic, the
Executive could compute
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217:. It was well received by both domestic and foreign markets, and
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Cockshott, Paul; Mackenzie, Lewis; Michaelson, Gregory (2012).
316:
315:
The calculator was powered by a Texas
Instruments TMC1802NC, a
245:
drain on the batteries that overheated them until they burst.
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The
Executive was launched in September 1972 at the price of
900:
507:
349:
batteries, equivalent to about four months of normal usage.
357:
The screen on the Executive was a monolithic seven-segment
166:
Its small size was made possible by pulsing current to the
324:
480:"A sectioned Sinclair Executive pocket calculator, 1972"
791:"Clive Sinclair: "creative electronics" visionary"
406:"Sinclair Executive and Sinclair Executive Memory"
198:, equivalent to £1,330 in 2023 when adjusted for
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225:, 50 resistors and 17 capacitors, cost close to
937:
560:"Pocket calculators add up to a big market"
558:Information, Reed Business (20 July 1972).
557:
944:
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508:Cockshott, Mackenzie & Michaelson 2012
275:, and the futuristic design earned it the
27:
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229:, compared with a sale price of close to
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267:". One Executive is on display at the
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178:of profit for Sinclair and winning a
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454:"Have you got a Sinclair Executive?"
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374:Memory sold at the lower price of
155:, and the first to be produced by
14:
1038:
672:Rawsthorn, Alice (4 March 2012).
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151:was the world's first "slimline"
832:. Vintage Calculators Web Museum
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524:. Vintage Calculators Web Museum
519:
482:. Science Museum. Archived from
431:. Vintage Calculators Web Museum
426:
408:. Vintage Calculators Web Museum
403:
783:
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712:"Sinclair Executive calculator"
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170:TMS1802 "calculator on a chip"
674:"Farewell, Pocket Calculator?"
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513:
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1:
757:"Executive Pocket Calculator"
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319:integrated circuit with 7000
286:
7:
907:. Oxford University Press.
855:"Sinclair Executive Memory"
830:"Sinclair Executive Memory"
605:. www.vintagesinclair.co.uk
10:
1043:
904:Computation and its Limits
759:. The Museum of Modern Art
429:"The Calculator-on-a-Chip"
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994:Sinclair Wrist Calculator
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317:metal oxide semiconductor
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137:
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84:
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69:
56:
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33:Sinclair Executive Type 1
26:
739:"The push-button abacus"
737:Rowlands, David (1973).
182:Award for Electronics.
522:"Calculator Time-line"
305:floating decimal point
880:Dale, Rodney (1985).
456:. BBC. Archived from
1027:Sinclair calculators
953:Sinclair calculators
362:light emitting diode
269:Museum of Modern Art
79:Light-emitting diode
999:Sinclair Enterprise
984:Sinclair Scientific
486:on 12 December 2013
23:
1022:English inventions
989:Sinclair Sovereign
979:Sinclair President
969:Sinclair Executive
964:Sinclair Cambridge
883:The Sinclair Story
857:. mycalcdb.free.fr
710:Torrens, Richard.
582:has generic name (
215:Sinclair Radionics
211:sensitive to price
172:integrated circuit
161:Sinclair Radionics
149:Sinclair Executive
22:Sinclair Executive
21:
1007:
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168:Texas Instruments
153:pocket calculator
145:
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130:Power consumption
102:Texas Instruments
16:Pocket calculator
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369:Executive Memory
359:gallium arsenide
337:oscillator clock
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328:five seconds.
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311:Microprocessor
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277:Design Council
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180:Design Council
157:Clive Sinclair
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42:September 1972
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886:. Duckworth.
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133:20 milliwatts
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859:. Retrieved
834:. Retrieved
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619:
607:. Retrieved
572:cite journal
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526:. Retrieved
515:
510:, p. 90
488:. Retrieved
484:the original
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462:. Retrieved
458:the original
435:15 September
433:. Retrieved
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412:15 September
410:. Retrieved
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235:£2.5 million
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176:£1.8 million
165:
148:
146:
122:Power supply
85:Display size
75:Display type
18:
603:"Executive"
347:hearing-aid
342:capacitance
321:transistors
303:, or use a
297:reciprocals
223:transistors
159:'s company
47:Invented by
1016:Categories
861:6 December
836:6 December
763:6 December
717:23 January
683:6 December
609:6 December
528:26 January
490:6 December
464:6 December
382:References
333:transistor
138:Dimensions
70:Calculator
39:Introduced
813:Dale 1985
796:InfoWorld
778:Dale 1985
698:Dale 1985
657:Dale 1985
645:Dale 1985
624:Dale 1985
287:Functions
200:inflation
109:Frequency
104:TMS1802NC
98:Processor
88:8 digits
745:: 36–7.
323:. This
293:squares
265:machine
243:current
186:History
112:200 kHz
911:
890:
743:Design
566:: 144.
376:£24.95
353:Screen
249:Design
192:£79.95
335:. An
194:plus
117:Other
64:79.95
909:ISBN
888:ISBN
863:2013
838:2013
765:2013
719:2023
685:2013
611:2013
584:help
530:2014
492:2013
466:2013
437:2017
414:2017
147:The
57:Cost
325:CPU
271:in
231:£80
227:£10
196:VAT
93:CPU
1018::
846:^
820:^
805:^
793:.
741:.
727:^
676:.
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570:{{
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62:£
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
