First-Hand:Computer Hot Flashes and Cold Feet

Submitted by Sam Gibbs

Early computers were temperature-sensitive. Mainframe computers were housed in clean rooms with carefully controlled temperatures. Early on, we found that minicomputers were especially cantankerous about temperature. If it got too hot, the computer would lapse into stupidity followed by a deep coma. First, it would forget how to spell words. The word ‘rod’ might be rendered ‘rqt.’ Later on, it would forget how to do arithmetic. Then, finally, it would go to sleep, completely oblivious to its role in life. When put in a cooler room, it would regain its faculties.

Something similar would happen when it got too cold. It would lose its BBL. In this case, the letters are not an abbreviation for petroleum barrels. The letters stand for basic binary loader. Without its BBL, it could not read computer programs and execute them. On a cold morning, we learned to let the computer warm up before using it in any fashion. If we got in a hurry and didn’t warm it up, it would lose its BBL. Reloading the BBL was a hassle. The octal numbers had to be keyed in by hand through the front panel of the machine. Fat-fingered people who were cold and in a hurry could rarely get this done on the first try. Thankfully, modern microcomputers have wider temperature ranges and do not present these problems.

We at Nabla were very proud of our first computer analysis truck. It was a boxy looking delivery-type vehicle. We did a professional job of shock-mounting the computer behind the bulkhead to protect it from damage. The installation looked like an airplane cockpit with dials and gauges showing. On the first well that we tried to analyze, the computer swooned because of a high-temperature problem. We knew what was happening. My friend, Ken Nolen, is a mechanical genius, and immediately saw how to fix the problem.

We drove into the small ranching and oilfield town of Jal, New Mexico. In those days (1970s), Jal had a grocery store. Helpful folks in the store gave us some large cardboard boxes. Ken bought some masking tape, and with his sharp pocket knife, proceeded to solve the problem. In the grocery store parking lot, he re-ducted the air conditioning system (a window unit powered by a two-cylinder engine-generator). This time, he gave 75 percent of the cool air to the computer and only 25 percent to the people in the truck. Formerly, 75 percent was being given to the people and the remaining 25 percent went to the computer. The new ducting worked fine and we finished our job and went home. Soon after, Ken made the parking lot modifications permanent in the analysis truck.