Calculator Madness!

It was nearly Christmas 1974, and I was green with envy! I was at school studying for "O-Levels", and a friend came in with one of the new "electronic calculators". In a flash my 5-figure log tables and slide rule had become obsolete - this guy had complete mastery over numbers in a tiny package which fitted in his pocket and looked like something out of a Bond film! Being gadget mad (then, as now) I had to have one.
Please click on the thumbnails if you're nutty enough to want to see these beauties in all their glory!

Sinclair
Cambridge: This was many people's introduction to electronic calcs. It was tiny, affordable, and it outsold just about any other model in the UK. It also had a lifespan of several years during which the price dropped nearly tenfold! A classic, and the product Sinclair is most often remembered for (apart, maybe, for the computers). It was also available as a kit (can you imagine a kit calculator nowadays?!) Sinclair Cambridge
Cambridge Scientific: Even more of a classic! The first affordable "Scientific" for the "masses", the smallest one on the market, the first "single chip" scientific ... The list goes on. Apart from the hugely expensive Hewlett Packard, this was the forerunner to modern scientific calcs. Constants were printed on the case, functions were few (logs and trig only) and ludicrously low accuracy (3 figures at best!), and logic was RPN. Cambridge Scientific
Oxford 100: A desktop version of the Cambridge, developed a little later on. Superb styling - the picture doesn't really do it justice. Originally developed for Gillette to market in the USA. Oxford 100
Oxford 300: Scientific version of the 100. Came later on to the Cambridge and featured a proper set of functions and better accuracy, as did later Cambridges. Oxford 300
Executive: Sinclair's first calc (1972), and the first genuine "pocket" calc in the world. It used a Texas Instruments chip, and when Texas saw the final design they were astounded with how Sinclair had managed to make it so small (their own model was a lot bigger). Very stylish (it won a design award), very desirable, and virtually impossible to find now, unless you're willing to pay silly prices. Executive
Sinclair brochure All the things you could do with your new toy! Sinclair literature
CBM / Commodore
Commodore brochure Commodore / CBM (Commodore Business Machines) - they weren't sure what to call themselves, it varied with different models - was a very major player in the early calc market. The Minuteman (geddit!) was a very early model, and they went on to make some very nice scientifics, which were actually very good machines with excellent key action (no click!). Some of their top end scientifics must win awards for the greatest number of keys anybody has ever fitted on a pocket calc. Commodore made several LCD calcs in the late '70s, then got out of the market and went on to PETs and Amigas. Commodore literature
Commodore Scientific: Typical styling for the brand; very good looking, in my view. Commodore Scientific
Texas Instruments
T.I. brochure Texas is a rare example of a company that was in from the very start, and still finds it profitable to make calcs now. In fact T.I. is credited with making the first "pocket" (big pockets!) calc, circa '71. Very competent machines, but personally I hate the "click" keys! Were famous for their late 70s, early 80s, 57, 58, and 59 programmable machines which were very popular - they had an early example of a plug-in software ROM module which enabled different users to gain program functions suitable for their own purposes (ie: electronic engineering, financial, aeronautical, etc). Texas Instruments brochure
Texas SR-51a: A very popular earlier model with typical T.I. styling. SR51a Calculator
Rockwell
Rockwell 18R: A typical early machine with distinctive Rockwell styling. Despite the unlikely looking rounded, knobbly keys, these machines had very good key action and were excellent to use, particularly when the green fluorescent displays were used. Rockwell came into calcs from the angle of making the chips, and their chips were fitted to a lot of other makes of calcs. They continued till the late 70s with a few LCD models before getting out in a hurry when the calc business got unprofitable with the influx from the Far East. Rockwell Calculator
Bowmar
Bowmar brochure Mmm .. which model should I go for, the Brainstorm or the Brainmaster?! Seriously, although Bowmar wasn't the best known name (in the UK, at least), they came in from the "LED display manufacturer" angle - they produced some of the earliest 7 segment LED strips, and their displays were fitted in lots of other manufacturer's machines. The two machines illustrated look virtually identical to their earliest calcs, which were in turn rebadged examples of T.I.'s earliest machines (someone correct me if I'm wrong). Didn't stay in the calc business that long, though, as far as I know. Bowmar Calculators

Back button...back to reality.