Data evaluator using an adjustable endless loop magnetic tape

摘要

A data evaluator employing an endless loop which has the capability of eliminating a standard signal from a test signal so as to result in the depiction of an accurate defect signal. The data evaluator of the instant invention generally comprises two record and play back heads, an endless loop which travels an endless path across the opposed record and play back heads, and a synchronizing device employed to synchronize the signals which simultaneously are played across two opposed record and play back heads.