Self-Test of Digital Evaluation Equipment

Digital Evaluation Equipment (DEE) is a programmer-controlled concept for building block test equipment. A particular system consists of a computer/controller, measuring system, stimulus generators and power supplies. DEE self-test utilizes a dual function concept; (1) automatically programmed testing, and (2) individual self-test of each building block. Since a DEE system encompasses a large test capability, the equipment is complex and design efforts have been concentrated on optimum use of the system to check itself. Self-test design is divided into the areas of systems testing and monitoring techniques. The programmed system testing uses the measuring equipments in the system to determine the operability of the various stimuli generators. The measurementunit is automatically self-calibrated with internal standards to assure that the system accuracy is maintained. The computer is self-tested using magnetic and/or paper tape depending on the degree of malfunction. The design of the programmed self-test is based on automation of all basic test functions that can be reduced to hardware without greatly increased complexity. Manual operations using military personnel are minimized. Self-test circuits are described for monitoring both digital and analog parameters. The types of circuits are described along with the criteria of their selection to perform the monitoring functions.