PLATTENFOERMIGES AUFZEICHNUNGSMEDIUM MIT FESTWERTSPEICHER-SPUREN, BESCHREIBBAREN BEREICHEN UND MIT ANTRIEBSEINRICHTUNG

摘要

A record disk has a read-only track area and a writable track area in which a guard band of a sufficient width is formed between such two areas for prevention of erroneous writing into the read-only track area during data writing into the writable track area. Apparatus using such disk employs a pair of heads with opposite azimuth angles and erasing of a track is first checked to prevent a read-only track from being erased. During such track erasing, a track recorded by a head with one azimuth is erased by a head with the other azimuth.