Field store standards conversion: equalisers for ultrasonic quartz delay lines

摘要

A field-store standards converter has been built which uses fused quartz delay lines as the storage medium for the television signal. The associated amplifiers, which have been described elsewhere, contain equalisers which allow the gain and group-delay to be adjusted so that the overall delay-unit response lies between very close, specified, limits. The present report describes the design and adjustment of a novel form of active equaliser and the development of equipment for the detailed examination of the responses of the delay-unit.