公开(公告)号：US3571527A

公开(公告)日：1971-03-16

申请号：US3571527D

申请日：1968-01-16

Applicant: IBM

Inventor： BECKER FRANK E ,  KLEIN WALTER F ,  YOUNT WILLIAM R

IPC: G06K1/04 ,  G11B5/80 ,  G11B5/86

CPC classification number: G06K1/04

Abstract: The invention concerns methods and apparatus for establishing accurate positioning and registration of master and duplicate magnetic record media during a magnetic transfer operation to insure compatibility of each kind of media in a utilization device. The invention is particularly useful with media having magnetic signals recorded according to a Boustrophedonic pattern. Such a pattern is created when the record head traces a signal path having a plurality of tracks with, as an example, tracks 1, 3, 5, 7, etc. recorded left to right, tracks 2, 4, 6, 8, etc. recorded right to left, and wherein the head steps a fixed distance at the end of each track.

公开(公告)号：US3536855A

公开(公告)日：1970-10-27

申请号：US3536855D

申请日：1968-01-16

Applicant: IBM

Inventor： GARDNER CHARLES L JR ,  KLEIN WALTER F ,  YOUNT WILLIAM R

IPC: G11B5/86

CPC classification number: G11B5/865

公开(公告)号：US3588380A

公开(公告)日：1971-06-28

申请号：US3588380D

申请日：1969-03-21

Applicant: IBM

Inventor： HORLANDER FRANK J ,  YOUNT WILLIAM R

IPC: G09B5/06 ,  G11B5/02 ,  G11B5/86 ,  G11B25/04 ,  G11B5/44

CPC classification number: G11B25/04 ,  G09B5/062 ,  G11B5/02 ,  G11B5/865

Abstract: EDUCATIONAL APPARATUS IN THE FORM OF A RECORDING/REPRODUCING UNIT ACCOMMODATES A RECORD MEDIA COMPARABLE IN SIZE TO THE FAMILAR IBM TABULATION CARD. THE MEDIA HAS PRINTED INFORMATION ON ONE SIDE SUCH AS QUESTIONS AND ANSWERS, CIRCUIT DIAGRAMS, ETC. THAT IS VISIBLE TO THE USER WHEN IN OPERATING POSITION AND RECORDED INFORMATION ON THE OPPOSITE SIDE POSITIONED FOR SCANNING BY A TRANSDUCER DURING PLAYBACK AND RECORD MODES. ONE FEATURE OF THE MACHINE IS TO RECORD AND PLAYBACK SPEECH WHILE USING TWO DISTINCTLY DIFFERENT MAGNETIC RECORDING MATERIALS. THE FIRST MATERIAL (MASTER CARD) REPRESENTS THAT USED FOR THE DIRECT RECORDING OF MASTER RECORDS. IT IS OF HIGH COERCIVITY AND HIGH RETENTIVITY. THE SECOND MASTER (COPY CARD) HAS RELATIVELY LOWER MAG-

NETIC PROPERTIES. IN ORDER TO RECORD AND REPRODUCE WITH THE TWO DIFFERENT MATERIALS ON A COMMON RECORD/PLAYBACK MACHINE, THE CIRCUITS CONTROLLING THE HIGH FREQUENCY BIAS AND SIGNAL RECORDING CURRENTS ARE CHANGED DEPENDING IN THE TYPE OF MATERIAL USED. THIS IS ACCOMPLISHED BY ELECTRICAL SWITCHING OF EITHER OF TWO EQUALIZATION AS BIAS AND PREEMPHASIS NETWORKS IN THE RECORD CIRCUITS RELATED TO THE MASTER AND COPY MEDIA WHICH OCCURS AUTOMATICALLY WHENEVER THE RESPECTIVE MEDIA IS INSERTED. THE MASTER MEDIA IS INTENTIONALLY OVERRECORDED TO COMPENSATE FOR NOMINAL AND EXTREME SIGNAL LOSSES EXPECTED TO BE ENCOUNTERED WHEN THE MASTER MEDIA IS USED AS A SOURCE DURING A LATER MAGNETIC TRANSFER OPERATION.

公开(公告)号：US3463888A

公开(公告)日：1969-08-26

申请号：US3463888D

申请日：1965-12-30

Applicant: IBM

Inventor： YOUNT WILLIAM R

IPC: G11B15/02 ,  H03F3/08 ,  H03G1/00 ,  H03G7/00 ,  H03G7/06 ,  H03G7/08 ,  H03F17/00

CPC classification number: H03G7/06 ,  G11B15/02 ,  H03F3/08 ,  H03G1/0047 ,  H03G7/004 ,  H03G7/08