John Ellenby, computer engineer who made laptop technology possible

John Ellenby, a Britishborn computer engineer who played a critical role in paving the way for the laptop computer, died Aug. 17 in San Francisco. He was 75.

His son Thomas confirmed the death but said the cause had not been determined.

Mr. Ellenby’s pioneering work came to fruition in the early 1980s, after he founded Grid Systems in Mountain View. As chief executive, he assembled an engineering and design team that included the noted British-born industrial designer William Moggridge.

The team produced a clamshell computer with an orange electroluminescent flat-panel display that was introduced as the Compass. It went to market in 1982. The Compass is now widely acknowledged to have been way ahead of its time.

“The Grid Compass was the first successful clamshell laptop computer,” said Marc Weber, a historian at the Computer History Museum in Mountain View.

It went on to become a valuable tool for big corporations, government spies, White House and Pentagon officials, and even astronauts, surviving the midair explosion of the space shuttle Challenger in which seven people died.

The Compass came with advanced, and expensive, data storage capacity called bubble memory and was accordingly pricey, originally selling for $8,150 ($20,325 today). As a result, it found an enthusiastic market not with consumers but rather in Washington.

One version, intended for U.S. special-operations forces, was said to have come with a red dot on its black magnesium case, placed there as an aiming guide for any commando who might have to shoot the device to destroy its data quickly.

Intelligence agencies were also eager buyers; the Compass was marketed as a kind of sexy, hightech device that might appeal to James Bond.

NASA also used one as a backup navigational device in its space shuttle program. One was aboard the Challenger on the morning of Jan. 28, 1986, when a rocket-booster failure destroyed the craft shortly after liftoff from Cape Canaveral. The Compass, which had been attached to a dashboard with Velcro, was recovered from the debris and found to be still working.

Mr. Ellenby was born in Corbridge, in northern England, on Jan. 9, 1941, to Conrad Ellenby, a zoologist, and the former Mary McCarraher, a biologist. He studied economics and geography at University College London and spent a year in the early 1960s studying at the London School of Economics, where he encountered mainframe computers.

He later worked for the British computer maker Ferranti and lectured on computing at the University of Edinburgh in Scotland. He moved to Northern California in the early 1970s to work for the Xerox Corp. at its Palo Alto Research Center.

At the time, Xerox was designing a desktop computer, known as the Alto, which would become an inspiration for the Apple Lisa and Macintosh, and for Microsoft Windows. Inside Xerox, the Alto was known as an “interim Dynabook,” a reference to the prototype for a portable machine envisioned by the Xerox computer scientist Alan Kay.

Mr. Ellenby was instrumental in managing the development of the Alto II, a version of the prototype that could be manufactured more easily. He had earned a reputation as a technologist who was adept at turning technologies into products.

“He was good and aggressive and even daring, you might say,” said David Liddle, a Xerox executive at the time.

Mr. Ellenby left Xerox to found Grid in 1979. The move paid off. In addition to his government customers, corporations like Bank of America, Chevron and McKinsey & Co. were early buyers.

Weber, the computer historian, said that the name Grid was derived from Mr. Ellenby’s vision of a gridlike network — a precursor to the Internet — that would connect various computers with one another, allowing them to share files. The idea was to sell the system through a business services company. The company called the system Grid Central.

Initially, the Compass was so energy-hungry it required a plug. And the machine took competitors by surprise. One was Adam Osborne, the developer of the Osborne 1, an early portable computer — a “luggable,” in industry parlance — about the size of a sewing machine. Appearing with Mr. Ellenby on an industry panel, Osborne was startled to realize that the device sitting flat on a table nearby was, when it was opened, a portable computer.

Mr. Ellenby sold Grid to the Tandy Corp. in March 1988. He went on to start Agilis, a maker of handheld tablet computers, and, with his son Thomas, GeoVector, which pioneered navigation and augmentedreality applications.

In addition to his son Thomas, Mr. Ellenby is survived by another son, Peter, and a granddaughter.