Coding Electronic Equipment to Facilitate Maintenance

The aim of this study was to improve maintenance of electronic equipment by determining what information to place on the equipment and developing techniques for its display. Trips to various communications installations were made in order to examine equipment, observe maintenance activities, examine manuals, and interview personnel. Detailed data were collected showing the marked variation between observed test point readings and those called for in maintenance manuals. Recommendations were developed concerning information to be displayed on prime electronic equipment, covering 1) designation of functional groupings, 2) identification of signal paths, 3) identification and sequence for using test points, and 4) presentation of historical information for each test point. These recommendations were evaluated by incorporating them on an oscilloscope; comparing this ``coded'' scope with an identical uncoded one showed that trouble-shooting time was reduced on the average to approximately one-half that for the uncoded equipment.