REMINISCENCE - UNIVAC

by BERNARD A HODSON

At the time of the first commercial computer, called UNIVAC 1, both IBM and UNIVAC (Remington Rand), had electronic calculating systems, the UNIVAC version known as the 120. These did not have internal memory but were programmed externally by wires. The 120 had two large boards containing hundreds of connectible holes, some designated for instructions, (maximum of 40), and some for numeric data. Alphabetic data was mainly stored as punched cards. An application had to be physically wired, along with the data values, meaning a different set of boards for every application. Because of the limited number of instructions the application might be split into two or three runs, with intermediate results being passed from one run to the next, on cards. UNIVAC staggered IBM by creating a general purpose board in which only one pair of wired boards was necessary, applications being programmed by holes punched in cards, not quite the modern computer but moving towards it.

Besides magnetic tape UNIVAC 1 used data punched on cards extensively. These contained ninety columns, each with the coded equivalent of a character or number. The data storage device was a cardboard box. Data on these cards entered the computer via card readers.

The UNIVAC 1 was monstrous, about three metres long, two metres wide and almost three metres high, costing several million dollars. It was possible to walk inside it because most of the circuitry was on the outside walls, to help with the cooling. It took enormous power, so much that when it was switched on the surge dimmed all the lights in the neighbourhood. It was also itself susceptible to local power surges. It used water coolers which vented to the outside. When one was installed at the Sun Life Insurance company in Montreal the cooler in their office tower produced visible vapour in cold weather, which came to be known as Unismoke.

The UNIVAC memory consisted of a large tank of mercury, which had to be at a constant temperature, taking about 20 minutes to reach operating temperature. The technique for storage with mercury was to convert electrical signals to sound signals which went through the mercury as sound waves. At the other end they would be converted back to electrical signals. By knowing the speed of sound in mercury you knew when any particular data might be available.. Other devices at the time used what were known as nickel delay lines, which operated on a similar principle. The time to get the data while it was in the mercury (where it was unavailable for use) was called the 'latency time'.

At this time UNIVAC application programming was in a machine like language but a Commander in the US Navy called Grace Hopper, attached to the company head office in Philadelphia, was attempting to develop an English like language for the programming of business applications. Canadians helped in the early editions of the language. Initially it was called B0 but was changed to B1 for obvious reasons. It was a very symbol oriented language at the time but in later years was improved considerably becoming the almost universal language for programming business applications, called COBOL (COmmon Business Oriented Language).

The next UNIVAC development was a smaller and more business oriented computer called the UNIVAC File Computer. It had an innovation which was not repeated in the industry for many years. This was a hardware round robin switch that enabled the filing of data on one of several segments of a file storage device.

In selling computers one problem was how to analyse a customer's needs at a reasonable cost. This analysis could be time consuming. Two staff members established a technique which was to be the company pattern for many years, called the 'broad brush study'. Briefly it is a technique of interviewing a representative selection of key managers plus a selection of the working group. It was a very effective way of doing things, and still is.

Besides cards UNIVAC used magnetic tape, in which data was coded along the length of a reel of metal tape. A character or number would consist of seven or eight magnetised spots across the width of the tape. Early tapes were quite heavy. UNIVAC developed a very useful 'key to tape' machine, known as a Unityper, which never did catch on, possibly because the data on the metal tape could not be seen.. With a card, if you knew the code, you could read the data, or it could be decoded with the characters printed on the card. Cards could be sorted by a machine but sorting algorithms had to be developed for magnetic tape operations.