Designing Maintainable Circuits

A study was conducted to answer certain questions basic to the design of more maintainable circuits. The subjects were 210 engineers, all of whom had considerable experience in electronics. Questionnaires, designed to elicit information on the primary factors affecting fault-location time, were devised for 13 representative circuits varying over a wide frequency range. A statistical analysis of the subjects´ responses was conducted to determine whether any general conclusions could be drawn from the replies taken as a group. Results indicated that certain parameters yield more trouble-shooting information on all circuits and that these parameters remain approximately the same for the whole frequency range studied. In addition, it was found that oscilloscopes were considered to be the most efficient test device available. This result points out a problem, since a number of studies have shown that technicians have difficulty in using oscilloscopes and, as a result, prefer meters. Suggestions are made for circumventing this problem. A number of other analyses pointed out areas in which no generalities could be drawn, e.g., regarding the most efficient test-point locations. An attempt was made to reconcile these problems temporarily until more data are available.