Build Your Own Sinclair ZX81... To Satisfy Your Lust For Power?!

The Sinclair ZX80 set the computing world on fire as the first computer available for under £100 ($200 in the USA). You could buy a kit version for a mere £79.95 including postage. Best of all, it was built using more-or-less off the shelf parts, so reproducing one almost 30 years later is a relatively straightforward task.

For those who didn't experience the wonder of Sinclair's debut machine the first time around, the cheesy-looking ZX80 featured a membrane keyboard that would look more at home on a bank machine or microwave oven, and the screen flickered while running a program. To add insult to injury, the measly 1K memory (a mere 1024 bytes) was shared by the program, video display and variable stack. It didn't matter. The breakthrough price ensured that tens of thousands were sold before the little machine was replaced by the million-selling ZX81 in 1981.

Now -- a few dozen laps around the sun later -- Grant Searle has cobbled together instructions for building your own ZX80/ZX81 reproduction. You'll need a total of 22 ICs plus a sprinkling of other components. He even provides a couple of membrane keyboard overlays to help you build your own Sinclair membrane keyboard.

Grant gets 10 out of 10 stars for an ingenious project, although I can't imagine more than about three deranged souls opting to go through the trouble of building their own Sinclair in this day and age, especially when any true fanatic can pick one up on eBay for almost nothing.

How to build your own ZX80/ZX81