Skip to end of metadata
Go to start of metadata

Page 6

After the first operational LINCs were delivered in 1963, the demand created by their success stimulated private industry to step in. A small company called Computer Operations took the LINC tape design and adapted it to other machines. Spear Corporation produced LINC machines first with the earlier design, then using microcircuitry instead of the older circuits used in the original LINC. Dick Clayton of DEC (who once worked in MIT's Communications Biophysics Group), with help from Clark, adapted the PDP-8 into a two-processor machine called LINC-8, that could accept either LINC or PDP-8 software. Clayton later modified LINC-8 into a single processor - the PDP-12, which DEC marketed successfully. Later, according to Clayton, now vice president of advanced manufacturing technology at DEC, they backed off from the original concept of LINC as an integrated lab machine in favor of larger market computers such as the PDP-11.

While the biomedical computing evolution was beginning, in Maynard, a western suburb of Boston, DEC was struggling to break out of a pack of competitors for the commercial and industrial market crumbs left by IBM. Kenneth Olsen, president of DEC, had a hole card which proved devastating to the competition: his background at Lincoln Lab. He not only knew the circuits that he helped design, but he and his designers at DEC also had access to computer ideas and the people who worked at Lincoln Lab.

Gordon Bell, DEC vice president of engineering wrote in 1978, that DEC's first product lines, the DEC System Modules, were "directly patterned after the circuits of the TX-0 and the TX-2." Two years after DEC was formed, Olsen decided to build and sell complete computers. He reached into Lincoln Lab to hire an engineer, Ben Gurley, who subsequently designed the PDP-1, DEC's first computer. Gurley borrowed liberally from TX-0 ideas to produce the PDP-1. After the modest commercial success of the PDP-1, DEC began to think small -- and cheap. Two years later, Gordon Bell designed the PDP-4 and PDP-5, the beginning of a trend at DEC toward small computers.

Bell acknowledged that "the LINC was one of the machines that had a great influence on (his) design." Earlier, Clark and Molnar, while walking in Harvard Square discussing ways to reduce the costs, had fixed on a 12-bit word for the LINC, in contrast to the larger word sizes of the day. The first widely commercially successful minicomputer, DEC's PDP-8, would mimic their choice. In tracing the origins of the PDP-8, a machine which, in essence, launched the minicomputer age, Bell begins with a discussion of LINC as "the first complete personal computer available to a user ... at a reasonable price." The LINC tape, CRT console, logic, and software clearly pointed the way for the evolution of the DEC machine.

Digital Equipment Corporation is now the second largest computer manufacturer in the U.S. Its early history makes clear that DEC's success relied largely on the machine designed for biomedical applications -- LINC. It may be impossible to track in any direct way the LINC of 1963 to the IBM PC or the Timex-Sinclair machine advertised in today's newspaper for $39.95. However, without LINC, the advent of minicomputers would certainly have been delayed. And every subsequent personal computer in the classroom, the home, and the business office, can trace its lineage back to LINC.

page 7