• Graeme Mason

Not-so-humble: The Story of the ZX Spectrum

As this month sees the ZX Spectrum celebrate its 40th anniversary, we’ve invited lifelong fan

and Retro Gamer launch editor Martyn Carroll to chart the history of the UK’s biggest small

computer.


When writing about the Spectrum it’s customary to focus on its outward appearance and

small form factor. It’s all too easy to call it modest, diminutive, unassuming, humble. Ah yes,

“the humble Speccy” is a phrase that rolls right off the tongue. But the Spectrum has always

been much more than that. If anything, it’s the antithesis of humble.

Let’s start with its deceptive size. The Spectrum was indeed small, measuring just 23cm

wide, 14cm long and 3cm deep. Its imprint was not much bigger than a piece of A5 paper.

Compare that to a Commodore PET, Apple II or any other beige box of the era. This was the

Clive Sinclair way. He liked to shrink stuff, be it digital watches, calculators or televisions. But

with his computers it wasn’t a case of looking at rival machines and miniaturising them for

the sake of it: they were exactly the size they needed to be.

The late Rick Dickinson, who designed the keyboard and casing for the Spectrum and its

predecessor the ZX81, has revealed that the process began with a simple question: how big

should a key be? It needed to be just big enough for an adult to comfortably press it. And

then: how many keys do we need? It was determined that 40 keys would be enough. So

working outwards from that, the size of the keyboard was established and then the internal

components were arranged to fit beneath it, inside a slick black case.


When it came to those components, the Spectrum was no modest upgrade over the ZX81.

Though a considerable success, the earlier computer was a true entry-level affair. It came

with just 1Kb of memory, no sound output and monochrome graphics. Despite releasing 13

months after the ZX81, the Spectrum was a significant step up. It shared the same Z80

processor but the memory was boosted to 16Kb as standard, with a 48Kb model available,

and an internal buzzer was added to provide rudimentary one-channel sound. Crucially, the

video hardware was upgraded to display seven distinct colours, plus black, which gave the

computer its name. High-resolution colour displays could eat up lots of memory (hello BBC

Micro), so hardware designer Richard Altwasser looked at how Teletext was encoded on TVs

and developed an efficient display system where each 8x8 pixel block was limited to a

foreground and background colour. This saved memory but resulted in the infamous colour

clash issue that became a characteristic of the Spectrum.

Another distinguishing trait was its keyboard. Rather than opt for traditional moving keys,

Dickinson pioneered a solution that utilised a rubber membrane. For many the keyboard,

with its look and feel of cool pallid flesh, was a compromise too far, yet it was vital in

keeping manufacturing costs and production times down. Thanks to this prudent approach

Sinclair was able to sell the 16Kb model for just £125 in 1982. Compare this to the

Commodore 64 (£299) and the BBC Micro Model B (£399) and you can see why the

Spectrum was such an attractive proposition. And then in early 1983, when Sinclair’s market

space looked to be invaded by the Oric-1 and Acorn Electron (cheaper BBC Micro), it

aggressively slashed the price of the Spectrum to £99 for the 16Kb model and £129 for the

48Kb version. It wasn’t a price war as such as the competitors couldn’t respond, which is

why Sinclair sold half a million Spectrums by August 1983 and its share of the UK personal

computer market swelled to 42 per cent.


Hardware sales fuelled software support and vice versa. As the Spectrum was flying off

shelves in high street stores, developers like Bug-Byte, Imagine, Ocean and Ultimate were

busy bolstering the growing library of tape software. Thanks to its fast CPU, quick screen

display, colour capabilities and a generous amount of memory (in the 48Kb model at least),

the Spectrum was a capable low-cost games machine. It may have lacked hardware sprites,

multiple video modes and all that jazz but in the right hands, it was a genuine contender. All

gamers needed was a joystick and some big kid smoking cigarettes next to them for that

arcade-at-home experience.


A ridiculous number of great games were released for the Spectrum in the 1980s. The usual

coin-op conversions and film/TV licences featured heavily, but there were enough original

titles to keep things fresh. In particular, there was a rich seam of quirky Britsoft titles like

Manic Miner (Bug-Byte), Monty Mole (Gremlin), Skool Daze (Microsphere), Everyone’s a

Wally (Mikro-Gen) and pretty much everything from Automata. The years 1984-1987 in

particular were a golden period for Spectrum gaming.

As the software improved the hardware stagnated. The Spectrum+ model was released in

1984 and featured a better keyboard and little else. Two years later the Spectrum 128

arrived in the UK, adding more memory and a proper sound chip, but the core hardware

remained the same, colour clash and all. Next-gen ‘Super Spectrums’ were rumoured to be

in the works but Sir Clive was preoccupied with his electric trikes and other doomed projects

that weren’t designed to play Jet Set F**king Willy. Amstrad acquired the failing Sinclair

computer business in April 1986 and continued to manufacture versions of the computer

until 1992. So all told the Spectrum was a going concern for an entire decade, during which

time some 5 million units were sold and more than 10,000 software titles were released.

That’s not a bad run for an 8-bit micro with a hardware spec conceived in 1981.

For lots of people, the impact of the Spectrum was not limited to its commercial life. Thanks

to the decent version of BASIC built-in to the machine, and the various assemblers that were

available, many owners dabbed in programming and started creating their own software.


This no doubt led them to more powerful systems but it was the Spectrum that opened to

door and inspired them to code.


This was no more evident than in September 2021 when the news broke that Sir Clive had

passed away. Social platforms were flooded with tributes from professionals who professed

to owe their careers to him and the Spectrum. It’s beyond doubt that the Spectrum played a

significant role in the growth of UK games and wider tech industries. Cut them open and

you’ll surely find deep traces of red, yellow, green and cyan.


This lasting legacy deserves to be celebrated, so on its 40th anniversary, let’s all doff our

hats to the definitely in-no-way humble ZX Spectrum.

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