Abstract: The disclosure describes a computer-aided instructional system for teaching a student to trouble-shoot a piece of equipment, such as a radio receiver, with a tester, such as a volt-ohm meter (VOM). In order to achieve this result, the receiver and VOM are simulated by non-operating components which are controlled by the computer to respond as if they were fully operative and functioning devices. A computer-operated display presents instructions to the student and monitors the student's responsive use of the simulated receiver and VOM. Additional instructions are selected for display depending on the nature of the student's responses. In this way, the student learns to analyze the equipment by proper use of the tester.