Sinclair attributed the higher failure rate of the kits to customers breaking the components by inserting or soldering them the wrong way, though the company admitted that there was a persistent problem with power supplies that affected both kits and pre-assembled ZX81s. Sinclair's advertising in the United States provides an illustration of how the company perceived the ZX81's purpose:

This approach to advertising was driven by Sinclair's reliance on mail-order marketing. It came with a high up-front cost in terms of purchasing space in publications but it had the advantage of ensuring that all sales were firm and pre-paid. A big splash on launch produced a large influx of cash at the outset of a campaign, though it did also depend on the advertiser having enough product to satisfy the initial surge in demand. The advertisements served an additional purpose of priming the market for over-the-counter sales by "getting the story across", as Clive Sinclair put it: "Not that big a proportion do buy on mail order, but they see the ads, and that helps to prepare them for buying when the item appears in the shops."

Sinclair himself became a focal point for the marketing campaign, putting a human face on the business, while Sinclair Research was portrayed in the media as a plucky British challenger taking on the technical and marketing might of giant American and Japanese corporations. As David O'Reilly noted, "by astute use of public relations, particularly playing up his image of a Briton taking on the world, Sinclair has become the best-known name in micros." The popular press soon latched onto the image. His "Uncle Clive" persona is said to have been created by the gossip columnist for Personal Computer World, while the media praised Sinclair as a visionary genius (or even, in the words of The Sun, "the most prodigious inventor since Leonardo"). As Ian Adamson and Richard Kennedy put it, Sinclair outgrew "the role of microcomputer manufacturer and accepted the mantle of pioneering boffin leading Britain into a technological utopia".

Pricing was central to the marketing strategy, as it had been through Sinclair's career. The ZX81 had been designed to meet a £70 price point and was launched at a price of £69.95 (built) or £49.95 (kit). One Sinclair brochure presented a side-by-side comparison of the ZX81 with the four machines that Sinclair considered its main rivals – the Acorn Atom, Apple II Plus, Commodore PET and TRS-80. The comparison highlighted the vast differences in cost, from £630 in the case of the Apple II Plus to just £70 for the ZX81, though even by Sinclair's own comparison the Apple was by far the more capable machine.

According to Sinclair himself, the £69.95 price was chosen after applying the "experience curve" developed by the Boston Consulting Group. Sinclair's prior experience in the calculator market had highlighted the fact that a product will be more profitable selling at (for instance) twice the manufactured cost than at three times. He could have launched the ZX81 at a higher price, marketing it in a more traditional way as a premium product, but chose not to. In effect, he used the lower price to establish an unassailable lead before the competition moved in.

An essential part of Sinclair's marketing strategy was to use regular cost-cutting at strategic intervals to maintain market share. Ian Adamson and Richard Kennedy comment that Sinclair's approach was "to secure and extend [his] market lead and panic the competition. While most companies reduce prices when their products are in steep decline, Sinclair tends to discount shortly after sales have peaked. The advantage of his approach is that vacillating customers are drawn into the fold while the product's promotion retains a commercial urgency, and the costings of the competition are thrown into utter disarray."

This tactic proved highly successful, with Sinclair announcing by March 1982 that it had sold 250,000 ZX81s worldwide. 50,000 computers were sold each month, 60% outside the UK, despite Sinclair and W. H. Smith being the only distributors. Despite the launch of its successor, the ZX Spectrum, Sinclair reportedly intended to increase ZX81 production to 150,000 a month. When sales fell after the Spectrum's debut, Sinclair reduced the price of the pre-assembled version to £49.95 in May 1982. It was cut by another £10 the following April. Despite the increased competition from much more capable computers, the ZX81 was still shipping in excess of 30,000 units a month even as late as July 1983, more than two years after it had been launched. By that time, according to Sinclair Research, over 1.5 million ZX81s had been sold.

Selling the ZX81 over the counter was seen as something of a gamble and Rowland's colleagues were initially unenthusiastic about the scheme. Branch buyers thought that the ZX81 was unlikely to sell more than 10–15 units per branch at launch. Rowland himself thought that the ZX81 would sell about 10,000 units during the first five months of the retail agreement, equivalent to one month's mail order sales by Sinclair. Sinclair launched the ZX81 in the United States in November 1981 at a price of assembled () and in kit form (), initially selling directly to the American market by mail order. To be useful the computer needed an extra RAM pack which cost (). Sales reached 15,000 a month by January 1982, while American Express sold thousands more to its own customers. In February 1982 Timex obtained a licence from Sinclair to sell the ZX81 directly through thousands of US retail outlets, paying Sinclair Research a 5 percent royalty on all Sinclair hardware and software sold by Timex. The company was later to produce its own licensed clones and variants of the ZX81. By August 1982 Sinclair had lowered the American mail-order price of the assembled ZX81 to and kit to , and its advertisements stated that "more than 10,000 are sold every week". In December 1981 Mitsui obtained rights to distribute the ZX81 in Japan, selling it by mail order for (equivalent to £83 in 1982 prices), and had sold 5,000 units by July 1982. The Japanese market's favourable reaction to the ZX81 led Mitsui to begin selling the ZX81 over the counter in large bookshops from September 1982, with annual sales of 20,000 units predicted. In the Netherlands, the regular Sinclair ZX81 was for sale as well as a Bang & Olufsen branded version called Beocomp.

The ZX81 was also sold for a while in duty-free shops at UK airports. However, this fell foul of government export restrictions aimed at preventing the Soviet bloc countries from obtaining Western high technology goods. It was not uncommon for visitors from the Soviet Union and other eastern European countries to pick up gadgets in Western countries with the aim of transferring their technology to their own states' industries. In 1983 the government ordered that the ZX81s were to be withdrawn from sale at airports. There was no such restriction on sales to communist China and in November 1983 Sinclair Research announced that it had signed an agreement to export ZX81 kits to a factory in Guangzhou, where they would be assembled for the Chinese market.

Reception

right|thumb|A typical ZX81 setup including cassette recorder and black-and-white Ferguson television set|alt=ZX81 in between a copy of the "ZX81 BASIC Programming" manual and a cassette tape recorder, with a black-and-white Ferguson TV set on the background.

Reviews of the ZX81 highlighted the great value for money offered by the machine but noted its technical shortcomings. As Tim Hartnell put it in Your Computer, "the ZX81 is both a delight and a disappointment". He applauded the improvements that had been made over the ZX80, such as a much better manual, display and string handling, and called the ZX81 "a very good first computer" that "will open the world of computing to many who would be denied access to it by cost". However, the built-in memory was so small that use of a memory expansion pack was "mandatory for any worthwhile use". He also found the ZX81 to be alarmingly unreliable, having to have his first two test machines replaced before getting one that worked properly.

New Scientist's Malcolm Peltu commented that it was "great technical value for money particularly for computing enthusiasts" but thought that others were "likely to be bored very quickly by the basic system". He highlighted weaknesses in the manual and Sinclair's accompanying software, criticising them for "a misconceived design and sloppiness in execution which make the machine seem harder to use and more limited than it should" and questioned whether it might be more worthwhile to save up for a more powerful computer such as Acorn or Commodore's offerings. Overall, he concluded, the ZX81 might have a limited value in helping to teach BASIC programming and overcoming psychological barriers to computing, but "the Sinclair systems have a long way to go before they raise the quality and level of understanding of the nature and use of computer-based information systems among computer unbelievers."

While the editor of Personal Computer World was on holiday in May 1981, his colleagues publicised the magazine's review of the ZX81 with a cover showing a chimpanzee with the machine above the strapline "Editor benchtests the ZX81". (The chimp returned in later issues to "benchtest" all of Sinclair's subsequent computers.) The review, which was written by PCW staffer Dave Tebbutt, acknowledged that the machine had significant shortcomings but nonetheless represented "absolutely amazing value for money". He described the ZX81 as "a lovely product which will have enormous appeal to people wanting to find out more about computers, but without it costing them an arm and a leg" and concluded: "If you know nothing about computers and you want to enjoy finding out about them, then this machine offers a value for money way of doing just that. Children will love the ZX81, there can be no question about that, and I suspect that more than a few people who are already familiar with computers will buy one, just to have a bit of fun."

Paul Taylor of the Financial Times found the ZX81 to be "a powerful and flexible little computer ideally suited as a fun introduction to the mysteries of home computing" but cautioned readers about its limitations. It lacked ready-made software, the keyboard was not easy to use, it did not have sufficiently advanced graphics to be able to replicate arcade-style games and its built-in memory was inadequate. Even so, he suggested, "the ZX81 is a unique British product, part toy, part puzzle, part learning tool and I think that, provided one accepts its limitations and recognises that any computer will only do what it is told to do, it is good value as an introduction to the hobby of home computing."

The Age described the ZX81 as "not extremely sophisticated, and its memory capability is rather limited. It also has a rather toy-like appearance". It concluded that the computer was "an ideal toy for youngsters who want to become acquainted with the computer world. It is responsive, cheap, and very easy to use".

Billy Garrett of Byte, who already owned a ZX80, complimented the Timex/Sinclair 1000's manual (although he regretted the removal of the British original's humour), the "state-of-the-art circuitry", and the BASIC for being "remarkably powerful" despite the small ROM size. He concluded that "the major use ... will probably be for learning about BASIC or computers in general. [It] has limited expansion capabilities, and the keyboard is too small and cramped for any serious work".

Phillip Robinson of InfoWorld had no trouble using a $25 "department-store special" cassette recorder with his Timex/Sinclair 1000, but reported that friends could not use theirs. While also experiencing and having to compensate for the memory-expansion wobble, he stated his amazement at being able to purchase a complete computer with keyboard and BASIC "at digital-watch prices", approved of the documentation's quality, and surmised that Timex "is obviously gunning for the computer-literacy market ... at a price the masses can afford and are willing to spend". Robinson described the 1000's performance as "no slouch", especially its floating-point precision, and suggested using it as a single-purpose device devoted to one task while using another, larger computer.

David Babsky described the ZX81 as "a wonderfully brainy little micro which won't let you waste your time and make a fool of yourself". In a comparison between the ZX81 and IBM PC published in Which Micro?, he commended the ZX81's user-friendliness and its on-the-fly syntax checking of BASIC programs, which he described as "the feature that I, as a newcomer to computing, want to see incorporated into every micro."

Peripherals and software

right|thumb|A ZX81 connected to Sinclair's official peripherals – the notoriously wobbly 16 KB RAM pack and the ZX Printer|alt=ZX81 computer with a 16 KB RAM pack and a ZX Printer attached

right|thumb|Closeup view of the 16K RAM module, showing its edge connector

The success of the ZX81 led almost immediately to enthusiasts producing a huge variety of peripherals and software. Clive Sinclair was "amused and gratified" by the attention the machine received typewriter-style keyboards, more advanced printers and sound generators. A wide range of software was also published. Within only a year of the ZX81's launch, around 200 independent companies had been established to manufacture and sell Sinclair-compatible hardware. The people behind the ZX81 cottage industry were very often not computer professionals but were, as the Financial Times noted, "school teachers, civil servants, electrical engineers and technicians [who] have set up small operations in their own time". By August 1983 seven more ZX Microfairs were held, with the 14th ZX Microfair at Alexandra Palace in November 1984, still organised by Johnstone.

left|thumb|Many ZX81 owners replaced the machine's touch-sensitive keyboard with more usable add-on keyboards produced by third-party suppliers.

Thousands of ZX81 programs were published, either as type-in programs or as ready-made applications that could be loaded from cassette tape. Many computer magazines featured ZX81 program listings – some, such as Sinclair Programs, were dedicated entirely to listings – while many individuals became the archetypal "bedroom programmers", producing games and applications which they produced, marketed, recorded, and sold from their own homes. Some went on to found their own software houses, employing teams of programmers – some still at school – to produce programs for the ZX81 and other computers. Existing companies also sold software; Psion produced a series of ZX81 programs in close association with Sinclair, including a flight simulator, while ICL's range of ZX81 programs sold over 100,000 cassettes in less than three months.

Games

Enterprising programmers were able to produce games for the ZX81 using nothing more than text characters and the machine's limited text semigraphics. Some ZX81 games achieved lasting fame, such as 3D Monster Maze, a tense first-person perspective game that involved the player escaping a labyrinth with a Tyrannosaurus rex in pursuit. Written in a combination of BASIC and machine code, its innovative design led it to be hailed as the first home computer 3D game and a landmark in the history of computer and video games.

Clones and variants

right|thumb|The Timex Sinclair 1000, a licensed ZX81 variant produced for the US market by Timex in 1982–83. It was initially highly successful but sales soon collapsed.

right|thumb|The TK85, an unauthorised ZX81 clone produced by Microdigital Eletronica of Brazil

Sinclair's licensing agreement with Timex enabled the American company to produce three clones or offshoots of Sinclair machines for the US market. These were the Timex Sinclair 1000, Timex Sinclair 1500 (both variants of the ZX81) and the Timex Sinclair 2068 (a variant of the ZX Spectrum). The TS1000 was launched in July 1982 and sparked a massive surge of interest; at one point, the Timex phoneline was receiving over 5,000 calls an hour, 50,000 a week, inquiring about the machine or about microcomputers in general. It was virtually identical to the ZX81 save for re-branding and the addition of an extra 1 KB of memory, totalling 2 KB. In the five months following the TS1000's launch, the company sold 550,000 machines, earning Sinclair over $1.2 million in royalties.

Timex produced a second version of the ZX81 in the form of the TS1500, essentially an Americanised ZX81 launched in August 1983. It dispensed with the membrane keyboard and used a case similar to that of the ZX Spectrum, incorporating 16 KB of on-board memory. It was effectively a stopgap between the ZX81 and Spectrum. However, it was unsuccessful due to increased competition from rival US machines and the after-effects of Timex's botched marketing of the TS1000. Although the TS1000 had initially been a great success, Timex failed to provide the essential RAM pack upgrades to the market for two or three months after it launched the TS1000. Consumers would take the machine home, plug it in and find that it would not do anything useful due to the lack of memory.

In addition, consumers' attitude in the US was quite different from that in the UK. Clive Sinclair told Informatics magazine in June 1981 that "our competitors thought that consumers didn't want to learn programming. We [Sinclair Research] think they failed because of this and because of price." Timex evidently shared this belief but events proved it to be a false assumption. The TS1000/ZX81's price advantage was erased when its main rivals – the TI-99/4A and the VIC-20 – had their prices cut to below the all-important $100 mark. Competitors such as Apple, Atari, Commodore and Texas Instruments promoted their machines as being for business or entertainment rather than education, highlighting the value of computers with ready-made applications and more advanced features such as graphics, colour and sound.

By late 1983 Wayne Green reported a "rising chorus of frustrated Timex users who are telling friends not to waste their money". "Hard core" early adopters, he wrote, "became discouraged with the quality of the product, with the poverty of software available and with the almost total lack of information on how to cope with it". Consumers deserted the TS1000 once its novelty value had worn off and, as publishers of programming guides found to their cost, the American public showed little interest in using the machine to learn about computer programming. American retailers were left with large stocks of unsold machines. Burned by this experience, many were unwilling to stock the later Timex Sinclair machines in large numbers and the big chain stores dropped the Timex Sinclair line altogether.

Some companies outside the US and UK produced their own "pirate" versions of the ZX81 and Timex Sinclair computers, aided by weak intellectual property laws in their countries of origin. Several Brazilian companies produced ZX81 clones, notably the TK series (such as the TK85) from Microdigital Eletronica of Brazil) and Prológica's CP-200. Czerweny Electrónica of Argentina produced the CZ1000 and CZ1500, clones of the ZX81 and TS1500 respectively. Lambda Electronics of Hong Kong produced the Lambda 8300, based on the ZX81, which was itself widely copied by other Chinese manufacturers.

The machines were not all straight copies of the ZX81; some, such as the CP-200, came with extra memory and a larger case (often with a chiclet keyboard in place of the original membrane keyboard). One clone, the TL801 from TELLAB of Italy, could emulate either the ZX80 or ZX81 and switch between the two machines via a jumper.

Impact and legacy

The ZX81 had an immediate impact on the fortunes of Sinclair Research and Clive Sinclair himself. The company's profitability rose enormously, from a pretax profit of £818,000 on a turnover of £4.6 million in 1980–81 to £8.55 million on a turnover of £27.17 million in 1981–82. Clive Sinclair became one of the UK's highest-profile businessmen and a millionaire, receiving a £1 million bonus on top of a salary of £13,000. He received a knighthood in the Queen's Birthday Honours and the Young Businessman of the Year award in 1983.

The machine also had a widespread and lasting social impact in the United Kingdom, according to Clive Sinclair, purchasers of the ZX81 came from "a reasonably broad spectrum" that ranged from readers of the upmarket Observer and Sunday Times newspapers to the more downmarket but numerous Sun readers. The largest age group was around 30 years old.

Among those whose first experience of home computing was provided by the ZX81 are Terry Pratchett (who used it for "very primitive word processing"), Edward de Bono and – perhaps proving William Gibson's point – many video game developers including Charles Cecil, Raffaele Cecco, Pete Cooke, David Perry (whose first published game, a driving game, involved "a black blob avoiding other black blobs"), Rhianna Pratchett, and Jon Ritman.

Even 30 years after launch, the ZX81 has a German user forum, and one in English.

New hardware and software continue to be developed for the ZX81, including a ZX81-based webserver; the ZXpand, a combined SD card interface, 32K configurable memory expansion, and optional joystick port and AY sound interface; and new games on cassette tape by Cronosoft, such as Tut-Tut, Virus, One Little Ghost, and many more, as well as releases by Revival Studios, such as Avalanche, Mayhem, Down, Stairrunner and more.

See also

  • ZX81 character set

References

Bibliography

Books

News reports

Other sources

  • ZX81 Software Downloads