Test system for detecting a permanent defect and a temporary defect in magnetic recording tape

Claim 1

A test system for detecting a permanent defect and a temporary defect in magnetic recording tape comprising; (a) means including a single capstan roller and a single pinch roller for running magnetic tape linearly along a predetermined path in a predetermined direction, (b) a first magnetic head assembly having a write-head and a read-head, said write-head positioned at a fixed distance from said read-head and at an upper stream side of said path, (c) a second magnetic head assembly having a write-head and a read-head, said write-head positioned at a fixed distance from said read-head and at an upper stream side of said path, and having a length (l) between the read-head of said first magnetic head assembly and the read-head of said second magnetic head assembly, (d) a record circuit for providing a signal to be recorded to said write-heads of both said first and said second magnetic head assemblies, (e) a first and a second read circuit connected to outputs of the read-heads of the first magnetic head assembly and the second magnetic head assembly, respectively, (f) a first and a second defective-portion-detecting circuit connected to outputs of said first and said second read circuit, respectively, (g) a delay circuit connected to output of said first defective-portion-detecting-circuit, a delay time (t) of said delay circuit being t=l/V, where V is the tape feeding speed, (h) an AND circuit having a first input connected to output of said delay circuit, and a second input connected to output of said second defective-portion-detecting-circuit, said AND circuit determining whether both said first magnetic head assembly and said second magnetic head assembly have sensed a permanent defect, (i) an exclusive-OR circuit having a first input connected to output of said delay circuit, and a second input connected to output of said second defective-portion-detecting-circuit, said exclusive-OR circuit determining whether either said first magnetic head assembly or said second magnetic head assembly has sensed a temporary defect, (j) a first output terminal connected to output of said AND circuit for providing permanent defect detection, and (k) a second output terminal connected to output of said exclusive-OR circuit for providing temporary defect detection.