Experience in using neural networks for electronic diagnosis

British Telecommunication plc (BT) has an interest in developing fast, efficient diagnostic systems especially for high volume circuit boards as found in today´s digital telephone exchanges. Previous work to produce a diagnostic system for line cards has shown that a model-based, expert system shell can be most beneficial in assisting in the diagnosis and subsequent repair of these complex, mixed-signal cards. Expert systems, however successful, can take a long time to develop in terms of knowledge acquisition, model building and rule development. The re-emergence of neural networks stimulated the authors to develop a system that would diagnose common faults found on line cards by training a network using historical test data