Using Computers Since 1965

posted in: About Sigurd, Computers, Programming | 0

I was introduced to computers in 1965, and have worked & played with them (outside some time in the Peace Corps, Nepal) ever since. The first computer I used, a Bendix G-15, was old in 1965. It was set off in the corner of the local University’s computer center, away from the newer IBM 1620 and newest CDC¬† 9300 computers (model numbers from the archives of computer evolution). In the same room as the G-15 were a number of analog computers then still in use. They approached problem-solving through modeling differential equations in electronic circuits. A particular arrangement of circuits might represent, for instance, a chemical reaction. The CDC 9300 was a hybrid (last or near-last of its kind) in being able to incorporate analog circuitry along with a digital computer. Its FORTRAN IV compiler was a step up from the FORTRAN II on the IBM 1620.

Entering a program for the G-15 was a matter of typing it onto paper tape on a teletype, then feeding the tape into the computer (tape cartridge can be seen in the top panel of the computer pictured below, held place by the handle across its middle). The main memory was not today’s semiconductor RAM, not even the precursor core (magnetic donuts) technology. It used a rotating drum to hold programs – so hot-shot programmers would place consecutive instructions at an interval apart on the drum so that when one instruction had been completed the next would be just about to come under the read head, all lined up to be read, interpreted, and executed as quickly as possible, rather than waiting an average of 1/2 a rotation of the drum for the next instruction to be available.

I wrote programs in FORTRAN for a small civil engineering company for many years. I maintained & extended both a basic accounting system set up by IBM and the COGO (COordinate GeOmetry) program used by the engineers. I did the legwork to move them from an IBM 1130 to a DEC PDP 11/40 computer running RSX-11D, an early multi-user operating system. The latter never reached its full potential because the computer didn’t have enough RAM (which was quite expensive at the time) to handle multiple users.

I was lured from civil engineering by a “jack of all trades” position at the local university’s (DE, USA) College of Education (from wiring circuits for experimental data gathering to managing a lightly used unix system to working on an Old English Concordance to using the PLATO system). I moved from there to the university’s central computer support organization to be the first person specifically supporting the newly-introduced IBM PC, followed by adding the Apple Macintosh, and later other PCs.

It stuns me to consider the speed of tech evolution, and how it keeps evolving, rapidly. All mentioned above was before ubiquitous computers and the Internet, which have opened up seemingly unending new realms for evolution – for personal interaction, for access to tools and information, and so much more.