The Portsmouth Technical College took delivery of their Elliott 803 computer in 1964. It was originally housed in the Mathematics department, and served that department well for several years. But near the close of the 1960's, computing demands had increased, and the 803 was no longer powerful enough. So a replacement ICL computer was purchased, and the Elliott 803 was transferred to the Electrical Engineering department. This was to be our first digital computer.
The photos shown here were taken just before the computer was finally taken out of service and disposed of in the late 1970's.
Our installation had the extra 4096 word core store cabinet giving us a total of 8192 words of storage. However, we did not have any film storage units, so initally, we were entirely dependent on paper tape for program loading and data input.
But this 803 had landed in an electronics department, so although the computer was now old, we were determined to use our engineering skills to enhance it's I/O capabilities.
The first new piece of equipment to be purchased was an additional Creed teleprinter. This can been seen in the photo above sandwiched between the standard output teleprinter and the Westrex paper tape punch.
The electronics in the tape reader/punch/printer desk had the capability to drive a second printer, so normally it would have been easy to attach this extra printer. But this printer had an encoder on the keyboard, and we wanted to be able to type directly into the computer. In addition, we desired a type-ahead buffer on the input so that input would not be lost if we typed too fast. This was something that the 803's I/O desk was not designed for. So a complex piece of interfacing hardware was designed and built, and installed into the I/O desk to achieve this goal. Most of the hardware used Texas Insts. 7400 series logic, which was becoming very popular. But also needed was a lot of level conversion circuitry to change from the high voltage / negative logic used in the I/O desk. But the interface worked, and provided our first experience in direct computer I/O.
(More to follow soon)
