My engineering career had an inauspicious start. When I was a college sophomore, Burroughs Corporation (now Unisys) hired me as a coop student to work in its component test lab in Plymouth, MI. We performed component qualification tests for all of the parts used in the Plymouth plant and many other plants around the world.
As you might expect, we students were hired to do the grunt work. My first assignment was testing capacitors. I tested thousands of capacitors. I tested disk capacitors. I tested tantalum capacitors. I tested electrolytic capacitors.
I tested capacitors at room temperature. I tested capacitors at high temperature. I tested capacitors at low temperature.
I measured their capacitance, of course. I measured their series resistance. I even measured the solderability of the leads. (What the test procedure called for was for me to dip the leads in a solder pot and then estimate what percentage of the lead was covered with the solder.)
At the time, I thought the job was perhaps the worst job in the world. I wanted to design stuff, not test capacitors. Looking back on the experience, though, I can see that it wasn’t all bad. It got me started in testing, and I have spent my entire career working with or writing about testing and test equipment.
Since then, I have always been interested in test equipment. The instrument I used to measure capacitance was a rack-mounted digital capacitance meter from GenRad that used Nixie tube displays. It was my first experience with digital instrumentation, and I found it fascinating.
That job also got me interested in automatic test equipment. When testing capacitors, I had to record each measurement by hand on a piece of paper. I knew there had to be a better way. Today, we would connect that capacitance meter to a personal computer, which would not only automatically record the measurements, but also simplify the analysis as well.
I also gained experience with how calibration affects measurements. The head of our lab made it clear to me that I was not to use test equipment that did not have a valid calibration sticker. I have since turned into a real stickler for proper calibration.
That early training came in handy when I later became test engineering manager for a manufacturer of digital temperature indicators and dataloggers. To automate the test line, we built our own calibrators. Because we were working with millivolt-level signals and measuring them with microvolt-level resolution, we had to account for many factors to ensure we made meaningful measurements.
I also came away with a good understanding of how component values can vary within a lot of parts and how values can change when used in extreme environments. That experience came in handy when I wrote in-circuit test programs for printed circuit board assemblies. Because I understood the principle, I was able to more effectively set test limits.
I guess I was just cut out for a career in test. A couple of times I tried to move into test engineering, but things just never seemed to work out. Test is where I started and test is where I’ll stay.
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