Ten classic electronic calculators from the 1970s and 1980s

Casio FX-7000G (1985)

We make no excuse for including another Casio. By the mid 1980s, they were just about everywhere, with a few hardcore techies plumping for HP.

If you start at the bottom, the FX-7000G looks much like any of the company’s other models - but the screen at the top was the game changer. A 96 x 64 pixel dot-matrix display, it could work in line mode, with thirteen digits, or graphics mode. There was a series of built in graphs, or you could program it to display your own, and even display the results of stats functions graphically.

Source: ML5

Up to ten programs could be stored in individual slots, though there was a total of less than half a kilobyte of memory. The specs may sound puny now, but the top resolution of the BBC Micro and Research Machines 380Z micros found in schools around the time were 640 x 256 and 320 x 192, respectively. And neither would fit in your pocket.

Hewlett-Packard HP-28C (1987)

The HP-28C retained the Reverse Polish Notation beloved of some HP users, and added to it the RPL programming language - albeit on a device that had no way of storing programs permanently.

With 2KB of memory, and a four-line LCD screen, the HP-28C also had another novelty: flip open the cover, and there were two keyboards, not one, with the left half providing alphabetic entry.

Source: Oliver Bildsheim

On top of all that, the HP-28 was also the first calculator with an algebra system, making it possible to work with whole new types of problems, arranging or solving them far more simply than before. The following year saw an update, the 28S, which added lots more memory.

RPL carried on into the succeeding range, the HP-48 series, as well, and the company makes calculators that use Reverse Polish notation to this day. ®

Calcnote

Read all about Reverse Polish Notation, via BODMAS and the like, here.