发明名称 UN APARATO PARA MODIFICAR LA SUPERFICIE DE GRABACION DE UN DISPOSITIVO DE ALMACENAMIENTO MAGNETICO
摘要 <p>A technique for enabling authentication of a magnetic memory disk. Predetermined portions of preselected tracks on the disk recording surface are deliberately removed and the locations of the modified portions are recorded, along with an initial program routine. The portions are alternatively removed by mechanically abrading the recording surface using a stylus, by embossing the preselected portions and applying an abrasive member to the embossed raised surfaces, by burning off the portions with a laser, or by chemical etching. When the disk is inserted into a drive, an initial program routine recorded on the disk causes the drive transducer to seek the pretreated portions and attempt a write and subsequent read operation. A successful write/read operation indicates a counterfeit copy. This indication may be used to signal the operator or erase the entire program from the disk.</p>
申请公布号 ES535515(D0) 申请公布日期 1985.10.16
申请号 ES19150005355 申请日期 1984.08.30
申请人 DYSAN CORPORATION 发明人
分类号 G11B5/00;G11B5/012;G11B19/02;G11B20/00;G11B23/28;G11B33/10;(IPC1-7):G11B5/02 主分类号 G11B5/00
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