PRODUCTION FACILITIES FOR MULTI-TURN METALFILM TRIMMER RESISTORS PER SIGNAL CORPS TECHNICAL REQUIREMENTS SCS-127 AND MIL-R22097B (MODIFIED).
Quarterly progress rept. no. 11, 1 Jan-31 Mar 65.
WESTON INSTRUMENTS INC ARCHBALD PA
Pagination or Media Count:
Qualification testing of thirty five 35 each of the 200 ohms, 1K ohms, 25K ohms, 50K ohms and 200K ohms potentiometers is complete. The results indicate a number of problem areas with the primary one being the resistive film itself. Efforts to produce the thirty five 50 ohms potentiometers have been discontinued until a more reliable resistive film can be produced. The toroid contact spring with a round cross section has been evaluated. Excessive wear resulted in some cases. This is felt to be a film problem. Leaking of the potentiometer during the immersion test was found to result from insufficient thickness of the head gasket. Steps are being taken to correct the problem. The production glazing area has been set up and production runs made with very satisfactory results. It has been found that different methods of termination lead to variations of results obtained when the film is applied in an otherwise identical manner. This phenomenon is being studied first with the intention of learning more about the fundamentals which affect the film and second to determine which is the optimum termination method.