While cleaning up, I came across this programmable Texas Instruments SR56 calculator. I've kept it all these years, probably because in 1977 it sparked my career as an embedded software engineer.

How did that happen? After receiving the calculator, I soon programmed a small game on it. About a year later, someone asked me if a job as a software engineer would suit me. It sounded as good as any other technical job, so I decided to apply. During my interview with the head of a Philips Healthcare software group, I mentioned this calculator. He didn’t hesitate; I got the job immediately.

Now, almost 40 years later, I was considering selling it. Before offering it on eBay, I wanted to get an idea of its value. If it was too low, I would keep it. While researching online, I discovered that only a few years before '77, electronic calculators were rather rare, and most calculations were still done on mechanical machines. These calculators impressed me, especially considering they had been in use for many decades but were replaced in less than one.

Back in 2013  I was cleaning up some cabinets

Tiny’s Vintage Calculators

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So, I started to collect both late mechanical and early electronic calculators. My current collection includes some simple mechanical machines, but most are complex high-end models. By today's standards, the early electronic ones are simple, but at the time they were cutting-edge. To illustrate the rapid pace of development, I also have some complex, programmable calculators from the early '80s. These were the first steps towards today’s laptops.

The mechanical machines, in particular, seldom work properly. Most often, they need cleaning and lubrication. Some require repair or precise adjustment. I managed to do this thanks to fellow collectors who share their experiences online. This site is my small contribution.

Tiny Henst

My location:   

Best,  The Netherlands