The Wonderful Computers of Clive Sinclair Content from the guide to life, the universe and everything

The Wonderful Computers of Clive Sinclair

6 Conversations

The dawn of the 1980s saw a revolution in computing. In the 1970s and before, computers were enormous, room-filling devices accessed by many people at once, and owned by governments and universities. But in the late '70s and early '80s, a British inventor already well known for producing the first programmable electronic calculators and tiny, tiny televisions (ie, only about the size of a large hardback book) produced a series of computers which would change the face of computing in the UK and beyond.

The MK14

In 1977, Sinclair's first computer was not much - many modern digital watches have more computing power - and it was only available by mail order, in kit form. Despite this, over 50,000 units were sold, because a computer you could program in your own home was a real novelty and something enthusiasts had dreamed about. It had a massive 256 bytes of RAM (ie, a quarter of a kilobyte, or 0.0002% of the RAM of the quite old computer used to write this entry), an eight digit display like a calculator, and a keyboard with 20 keys.

The ZX80

The ZX80 was the first 'proper' computer for home users, and it crossed an important psychological barrier by being available, ready built, for less than £100. It had a case - no visible circuit boards here. It had a QWERTY keyboard - sort of - and a built-in BASIC interpreter, and, crucially, it displayed its results not on a row of LEDs, but on the user's television screen. Because of the limited power of the processor, the machine could not process and maintain a screen display at the same time - which meant programs requiring inputs in realtime - such as 'Space Invaders' - were impossible to emulate. It could still play static games like draughts or hangman, however. It had a whole kilobyte of built-in RAM (enough for simple BASIC programs), and allowed the user to store programs on an ordinary cassette recorder1. 70,000 of these machines were sold by mail order, although working versions are now extremely rare.

The ZX81

The ZX81 was by any standards extremely successful. This was due to a combination of factors. First, it was sold complete - power supply, leads, and computer all in a single box. It was the first truly plug-and-play machine. Second, after an initial period of mail order only (300,000 units were sold by this route) you no longer had to send off for your machine in the post - it was available on the high street. Strange as it may seem now, in 1981 there were almost no shops anywhere selling computer equipment. When the ZX81 was released through WH Smiths2, demand went through the roof. By February 1982, Sinclair's manufacturing rate of 40,000 units per month was unable to keep pace with demand. Some of the early press advertising for the ZX81 made some pretty outlandish claims for the machine - it was memorably described as being powerful enough to control a nuclear power station. While this was, to say the least, a little overstated, it was nevertheless ideally suited for electronics hobbyists to control things like home robotics. The wide availability of old working models means that the ZX81 has continued in such uses until very recently.

The ZX81 had a similar 'membrane' type keyboard to the ZX80, the same solitary kilobyte of built-in RAM (expandable to 16k using a notoriously wobble-prone plug-in 'RAMPak'), and a similar BASIC interpreter. But what set the ZX81 apart was its steady screen display. For the first time, realtime interaction with blocky characters on screen became possible. There was an explosion of software of all kinds for the new machine - mostly versions of the then enormously popular 2D shoot-em-up Space Invaders.

The ZX81 began the trend which saw the early videogame consoles - notably the Atari 2600 and the Mattel Intellivision - supplanted by machines which, while they could not at first compete for colourful graphics and noisy sound effects, caught the imagination of the public by offering them the chance to write their own programs. Many of today's professional computer programmers wrote their first subroutine on a Sinclair home computer.

Most importantly, from the point of view of video game history, the ZX81 was the computer which hosted the world's first ever 3D game on a home computer - JK Greye's 3D Monster Maze. A simple labyrinth is generated, and the player has to find their way out, all the while being stalked by a Tyrannosaurus Rex. The whole experience was rendered in what is now referred to as 'first person' view - ie, you see what you would see out of the eyes of the character in the maze, as pictured in the ZX81's rather blocky but still effective graphics. A quick play of this game on an emulator is recommended to all fans of Doom, Quake, Unreal, Half Life and all the other FPSs which are now so popular, as it really is the literal grandaddy of them all. It is difficult now to describe the impact this game had on a public who had quite literally never seen anything like it.

The ZX Spectrum

The ZX Spectrum was far and away the most successful of Sinclair's machines. It took the ZX Basic developed for the ZX81 and added commands for 'high resolution' (256x192) graphics (commands included DRAW and CIRCLE), colour (INK and PAPER), and sound (BEEP). It took the bonk-sensitive flat keyboard of the ZX81 and replaced it with rubber membrane described eloquently as the 'dead flesh' keyboard. And it was available with either a basic 16K or a massive 48K of RAM.

It's difficult to estimate how many Spectrums were sold around the world, for several reasons. First, the official machines were available in no less than seven distinct versions, from 1982's 16K original to 1988's Spectrum +3, with 128K of RAM and a built in floppy disk drive. Second, there were various semi-official Spectrum-type computers released in the US and other overseas territories by Timex, the manufacturers of the official Spectrum. And third, the machine's simplicity meant that pirate copies of it were common. Indeed, cheap Spectrum copies are still in production in Eastern Europe at the time of writing. Undoubtedly, however, the Spectrum sold millions of units throughout the '80s and into the '90s.

It was certainly one of the most important machines for the nascent videogame programming industry in Britain. Here was a gadget on which a single teenager, working alone in their bedroom, could, in a matter of weeks, produce a game which really could become a national bestseller. The archetype of these 'bedroom programmers' was surely Matthew Smith, who produced one of the greatest games of the 1980s, Manic Miner. Anyone completing a modern video game such as Metal Gear Solid is treated to a credits sequence showing the long list of the dozens and sometimes hundreds of people involved in its production. Many, indeed most, of the games produced for the Spectrum in the 1980s had a credit list one name long. The lone programmer would design and write the whole program, draw the graphics, compose and implement the music, and often even design the packaging the game came in. Teams of programmers like those we take for granted now were then a very unusual exception, not the rule.

Many of today's big names in the videogame industry got their start on the ZX Spectrum. Probably the most famous example is that of Rare Ltd, programmers of the seminal N64 game Goldeneye. Rare Ltd originally released games under the label Ultimate - Play the Game, games which regularly redrew the map of what was technically possible on a Spectrum. Classics such as Jetpac, Sabre Wulf and Knight Lore were ahead of their time and pushed the little computer to achieve feats its designers would never have believed possible.

Shortly after the Spectrum's launch, in 1983, Clive Sinclair - known to legions of owners of his computers as 'Uncle Clive' - was awarded a DCBE3 for services to British industry. This led his fans having to ponder whether he was now 'Sir Uncle Clive' or 'Uncle Sir Clive'.

Sadly, the Spectrum was to be Sinclair's last big success as a consumer product. His company was bought out by Amstrad4 in 1986, allowing Amstrad to continue releasing their Spectrum variants the +2 and the +3, and allowing Sinclair to concentrate on other projects.

The Spectrum is almost unique among computers, in that it can be legally emulated on your home PC. Check out The World of Spectrum for details.

Not a Sinclair Computer, Really...

An odd footnote to the history of the Spectrum was the Sam Coupé. It had nothing to do with Sinclair or even Amstrad, but was intended as 'the logical upgrade' from the Spectrum by its designers, Miles Gordon Technology. It offered limited backward compatibility with the old 48k Spectrum5 but offered the possibility of sound and graphics comparable to the by-then popular Amiga and ST computers. It was not a success, however, being plagued with hardware and software problems and never getting the solid software support vital to a new machine.

Other Projects

Sinclair did go on to produce other computers, but none were able to repeat the phenomenal success of the Spectrum. A few notes on each follow:


The QL (Quantum Leap) was envisaged as a business machine, to compete with the IBM PC and the Macintosh. Its dead flesh keyboard, unreliable Microdrive storage medium and general oddness meant it was never a success.


The Z88 was a machine ahead of its time. It was to all intents and purposes what we would now call a PDA - it had an address book, organiser, word processor, spreadsheet. It was a simple, light, black slab with a QWERTY keyboard, five years before there were any notebook computers and ten years before there were any PDAs. It ran on AA batteries, had a four line LCD screen, and by all accounts was actually quite good at what it did. However, it seemed that in 1988, nobody really wanted to DO what it did yet, and it was only modestly successful.


Although released under the Sinclair label, these machines were Amstrad releases and had nothing to do with Sir Clive himself.

Other Devices

Surprisingly perhaps, Clive Sinclair himself was never particularly interested in computers per se. His other subsequent projects included the ill-fated C5 electric car and the electric bicycle, the Zike. Both these creations involved important advances in motor and battery technology, but neither captured the public imagination. The poor performance of the C5 in particular has probably cemented 'Uncle Clive' in the public imagination as a stereotypically British heroic failure.

This is a very unrepresentative picture, however - given the surprising popularity of the MK14 and ZX80, and the huge successes of the ZX81 and Spectrum, it would not be a great exaggeration to credit Clive Sinclair with almost single-handedly inventing the computing industry in the UK, and providing the first learning tools for the programming talents who shape today's video games and information technology - this site included!

1At the time, a 20MB hard drive cost in the region of £2000 - which back then could buy you a small car.2A chain of UK newsagent/bookshops.3Dame Commander of the British Empire.4Makers of a competing range of machines, the CPC series.5You could play some of your old games on it.

Bookmark on your Personal Space

Edited Entry


Infinite Improbability Drive

Infinite Improbability Drive

Read a random Edited Entry

Categorised In:

Written by


h2g2 Entries

External Links

Not Panicking Ltd is not responsible for the content of external internet sites

Write an Entry

"The Hitchhiker's Guide to the Galaxy is a wholly remarkable book. It has been compiled and recompiled many times and under many different editorships. It contains contributions from countless numbers of travellers and researchers."

Write an entry
Read more