A tester for heads, discs, and read/write channels

This paper describes a microcomputer-controlled precision tester designed to evaluate a number of factors crucial in the development of a high performance disc drive. The tester is intended for use in head development, head-to-disc interface characterization, and analog read/write channel development. Issues considered in the design of the tester are the precision of head positioning, the accuracy of spindle rotational speed, the ease of read/write channel substitution, and the degree of program control required to meet key test parameters. The basic tester may be modified to permit conversion of this device to such task-oriented devices as servowriters.