Visit Guide
CALCULATORS
Sinclair Radionics was the market leader for calculators in England. It worked on this field from 1972 up until Sir Clive dedicated himself to computation.
On this section of the exhibition, we showcase most of the models we acquired. Starting with Sinclair Executive, the first pocket calculator in the world (small size with batteries), launched in August 1972. Its’ design was created by Richard Torrens, who won the Design Council Award in 1973.
Having a battery powered calculator was possible due to the ingenious technique discovered by Jim Westwood. In simple terms, it would periodically turn on and off the power supply to the screen, in an effect not perceptible to the human eye and also not compromising the equipment’s memory.
Executive Memory was launched by the end of 1973.
In August 1973, Sinclair Cambridge was released: the first of many calculators of this model. In March 1974, the following models were also released: Cambridge Scientific, Cambridge Memory, Cambridge Memory %, Cambridge Programmable (which was called Radio Shack EC-4001, and that we acquired), Cambridge Scientific, Cambridge Scientific Programmable and Cambridge Universal.
The Sinclair Scientific, launched in August 1975, was, in the former models of the range, similar do the Cambridge, but its was not from the same range. It possessed the particularity of being able to use Reverse Polish Notation (RPN). In 1977 the Scientific Programmable was released as well as the Scientific Programmable Mark 2 (powered by a 9V battery), later in the year.
In March 1975 the Oxford calculator range was released. It came as a result of an investment made by the Gillette brand, that subcontracted the development of a calculator that would later be launched and named Gillette GPA (also in exhibition here). Sinclair took advantage of the investment and released the Oxford 100 (a GPA clone), with keyboards available in three colours. This calculator was followed by the Oxford 150 (with ability to calculate percentages and square roots), the Oxford 200 (with memory), the Oxford 300 (with a limited scientific mode) and the Oxford Scientific. All these had been released by 1976.
In February 1977, the Wrist Calculator was available in stores. It was one of the most peculiar, visionary and ahead of its time products Sinclair had released. During the 80’s, wrist calculators with an LCD screen started to be marketed. Once again, it was sold in a kit and was, sometimes, impossible to assemble. Even still, it is estimated that over 10,000 units were sold. John Pemberton was the person who designed these calculators, all from products already available in the company’s inventory.
Also in 1977, and to celebrate Queen Elizabeth II’s silver jubilee, one of the best designed models to date was released: the Sinclair Sovereign. It was produced in the three colours you can see here on display (gold, silver and black). There was also a limited edition, which consisted of silver calculators with the monarch’s crest. John Pemberton also designed this model and was awarded the Design Council Award. It did not have much success due to the already high pressure of the market at the time, a result of the high release of LCD calculators.
Both the Sinclair Enterprise (release date: October 1977) and the Enterprise Programmable (release date: July 1978) were the last attempts at red LED screens in a lost fight against the much more efficient LCD calculators. These two models did not have a lot of success. The name was inspired by the presence of NEB in the shareholders’ board and company management at the time.
Some of the last models produced were ironically manufactured in Hong Kong. They were two desktop calculators: President (February 1978) and President Scientific (released shortly after).