Why reincarnate?

The ZX81 although cheap and affordable made that achievement possible by omitting a lot of hardware that was standard on other systems available at the time.  The ZX81 with its 1K RAM, membrane keyboard, low-resolution graphics certainly put it at the bottom rung of the computer ladder.

However, these limitations supported a UK cottage industry where solutions to major ZX81 hardware limitations were offered as upgrades. The adverts that peppered the computer magazines then, typically claimed they were turning the ZX81 into a professional computer: Memory extensions, External keyboards, I/O cards, Joystick ports, hard disk drive storage and even colour modules.

I was not unique in expanding the ZX81. This was the home computer revolution and many others (particularly electronics enthusiasts)  were upgrading and modifying their ZX81's and particularly in the early '80s when all the decent computers were relatively expensive. There were all sorts of projects to expand the ZX81, you could control robots and rumours even abounded of a ZX81 controlling a power station!

In fact, the ZX81 became synonymous with always being expanded with some new capability (not necessarily useful) beyond its original concept. In 1984, in a computer magazine, even I at a tender age recognised the ludicrous and dubious usefulness of some of the so-called expansions when an article about word processing was accompanied by a drawing showing a tongue-in-cheek presentation of a heavily expanded ZX81 vs a typewriter. I have since tracked down that drawing and present it below:

Your Computer Vol. 4 No. 12, 1984, p.53

The truth of the matter though, was that my ZX81 was on its way to that caricature and I was proud of it! - I believed my expansions had a purpose and implementing them taught me a lot about computers.

Now some 39 years after my first ZX81, and the theft of the expanded system I had developed, I have a desire to build such a system again. This time though, having more income at my disposal, time and skills, I want to produce something that looks professionally built, and makes use of any recent homebrew hardware, so that the ZX81 is fit for use (and being seen)  in the 21st century!



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