Abstract: A flaw detection system is provided in which a source of radiation is scanned across a web of moving material being examined for repeat defects. The web is divided into lanes for processing purposes, and flaw information derived from the surface of material being examined is processed to provide a two-coordinate matrix location (lane and down-web), which is stored. This circuitry without the matrix outputs has other applications. Separation distances of a repeat flaw in the same lane are compared with a predetermined list, and if a match occurs, future flaw locations are projected in that lane. A repetition of a predetermined number of flaw repeats in a given lane signals an alarm. A predetermined number of misses in a row will result in the clearing of that lane of the particular flaw that failed to repeat.