DISCOID RECORDING AND REPRODUCING MEDIUM

摘要

PURPOSE:To shorten the access time by providing a recording/reproducing medium concentric with a signal track to a part of a discoid recording medium where video and sound signals are recorded concentrically or spirally. CONSTITUTION:Sheet type magnetic media 52-67 are bonded to an area 10 at an inner circumferential part of an existing VHD type disk. Then a doughnut- shaped magnetic sheet 80 having an outer diameter 51 and an inner diameter 9 is bonded to said inner circumferential part of the disk with an adhesive agent and via an elastic matter 81. The surface of the sheet 80 is divided into 8 sectors 52-59 by a magnetic means, and guard bands 60-67 are provided among those independent sectors 52-59. While a magnetic recording track 50 which records and reproduces computer data on the sheet 80 forms a data memory containing 8 blocks which are synchronous with a video vertical synchronizing signal during revolution.