RIP Sir Clive Sinclair

[markjay]

Back in the Seventies , I worked in a Design office when the first small "affordable" calculators came out. Think they were Texas Instruments & one of the Designers bought one. They cost about a week's wage & only did basis calcs. I think Sinclairs first calculator which from memory was white & really affordable worked on Reverse Polish logic which was not really user friendly. This is how you used it
For example, to do the operation 3+4, on an RPN calculator we would press 3, ENTER, 4, +. A more common calculator would use 3, +, 4, ENTER (or the equal sign).

An uncle who was an engineer gave me a slide-ruler as a present when I was a child. I did learn how to use it, but never got the chance to put it through its paces - not properly, anyway - the TI-55 pretty much killed it off. I think I may still have it somewhere, in a nice leather case - they were a precision instrument and pretty expensive at that.

 

[ToeKnee]

During my GCE maths i could only take into the test a slide rule and logs book. Doubt if I could use a slide rule now though but definitely remember RPN calculators.

 

[Dryce]

Yes - some of the early calculators used reverse polish notation.
My brother had a Kovacs (sp?) which also used this

RPN was unambiguous.

It meant there was no ambiguity or implicit state with regard to operator precedence or parentheses.

 

[Darrell]

I just googled RPN. Kinda wish I hadn’t.

 

[chic0821]

Log books & slide rules in exams for me. Some people used to write the formulas for some exams on the centre bar of the slide rule. Obviously not me
We had to design gear train layouts for Automation machines using 9 figure logs which took about a week to do. The company invested in an early calculator which cost thousands & reduced the time to about 2-3 days. Nowadays a £20 scientific calculator could probably do it in a day max. Oh happy days
A German designer joined the firm & had a "coffee grinder" calculator which was a sophisticated slide rule (pic included) You had to input your figure in the central part, wind the handle then it gave you your answer. His hands just flew around this & he was so fast. He taught some of us how to use it but never to his standard

 

[BTB 500]

During my GCE maths i could only take into the test a slide rule and logs book. Doubt if I could use a slide rule now though but definitely remember RPN calculators.

Same here, but when I did my A levels calculators were allowed (I had the white Sinclair Scientific). I wouldn't have a clue about using a slide rule now - I actually found mine when getting ready to move house recently!

The partial autobiography of writer Nevil Shute was called 'Slide Rule' - he was an aircraft and airship engineer. Working on the R100 airship involved huge numbers of calculations

The stress calculations for each transverse frame required computations by a pair of calculators (people) for two or three months. The simultaneous equation contained up to seven unknown quantities, took about a week to solve, and had to be repeated if the guess on which of eight radial wires were slack was wrong with a different selection of slack wires if one of the wires was not slack. After months of labour filling perhaps fifty foolscap sheets with calculations "the truth stood revealed (and) produced a satisfaction almost amounting to a religious experience".

 

[Deleted member 126251]

Back in the Seventies , I worked in a Design office when the first small "affordable" calculators came out. Think they were Texas Instruments & one of the Designers bought one. They cost about a week's wage & only did basis calcs. I think Sinclairs first calculator which from memory was white & really affordable worked on Reverse Polish logic which was not really user friendly. This is how you used it
For example, to do the operation 3+4, on an RPN calculator we would press 3, ENTER, 4, +. A more common calculator would use 3, +, 4, ENTER (or the equal sign).

RPN was also pretty common (standard?) on HP calculators. I had a HP41C (early 80s) which had all sorts of attachments and modules. I Still have a HP17Bii that I purchased in the late 80s and I still use it. I’m so used to RPN that I prefer to use it when I can.

 

[grober]

Hidden Figures great movie.

To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.

Accept third party cookies

]