Bipolar magnetic recorder
    16.
    发明授权
    Bipolar magnetic recorder 失效
    双极磁记录仪

    公开(公告)号:US2696420A

    公开(公告)日:1954-12-07

    申请号:US20077750

    申请日:1950-12-14

    Applicant: IBM

    Inventor: ROTH ROBERT I

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