British company announces inexpensive computer: The Sinclair ZX81 will sell for $149.95

BOSTON, MA – Sinclair Research, Ltd., a British company that makes the low-cost ZX80 personal computer, has announced its latest model, the ZX81. It is an eight-bit, Z80A-based machine with 1K static memory and 8K ROM. It costs $99.95 in kit form and $149.95 assembled.

“Our market is the hobbvist; also a large volume of sales is to the man on the street,” said Clive Sinclair, the company’s founder and president.

And the man of the street seems interested. Sinclair has recorded 100,000 unit sales since it introduced the machine in Britain in March. This figure equals last year’s total sales for the ZX80 model.

The ZX81 is based on a four-chip design unlike that of most microcomputers, which have between 12 and 20 chips. This economy of chips and additional new circuitry accounts for the low sticker price, according to Sinclair.

The 40-key, pressure-sensitive keyboard gives the equivalent of 91 keys, using a function mode and a single-press kevword system. The ZX81 does not have a dedicated video-display unit, but plugs into a television set, resulting in a black-and-white display of 24×32-character lines.

The ZX81’s memory can be expanded to 16K with a S99.95 expansion module. Sinclair also said that British manufacturers have come up with a 5 1/4-inch disk system. “We are developing a micro-floppy system for introduction next year, “he added.

He stressed the company’s policy of doing all the designing in-house and subcontracting for the manufacturing process. At present, a Timex plant in Dundee, Scotland, makes all the ZX81 machines. In Britain, the company sells a 50-character-per-second electrosensitive printer for the ZX81. The printer needs FCC approval before it can go on sale in the U.S., and, as yet, Sinclair has not submitted it for testing.

Sinclair Research offers a few software cassettes for the ZX81. Each cassette costs S9.95 and contains up to six business, household, educational and entertainment programs. Independent software publishers also distribute packages for the ZX81. Sinclair said he sees a need to compile a directory of available products, but nothing has been done as yet. The company uses mail-order marketing to sell its computers. It plans to look into retail sales when it becomes cost-effective, however. In addition, American Express will mail information about the ZX81 to its cardholders.

At present, the company has 20,000 ZX81 micros in this country. If sales run at 20,000 a month, as projected, the ZX81 will be “the best-selling personal computer in the world,” as Clive Sinclair predicted.

So far, the company has experienced a “2% return rate” on its machines in Britain, which means that 2000 of the 100,000 units the company has sold have needed service. Sinclair maintained that this is the lowest rate of returns among microcomputer manufacturers.

Sinclair said he didn’t feel the ZX81 was in competition with Apples and TRS-80s. These machines are directed toward the small-business market. The small memory capacity of the ZX81 limits its applications in that area, and that is why Sinclair markets the machine strictly as a personal computer.