GB1403804A - Magnetic tapes - Google Patents

Magnetic tapes

Info

Publication number
GB1403804A
GB1403804A GB1124573A GB1124573A GB1403804A GB 1403804 A GB1403804 A GB 1403804A GB 1124573 A GB1124573 A GB 1124573A GB 1124573 A GB1124573 A GB 1124573A GB 1403804 A GB1403804 A GB 1403804A
Authority
GB
United Kingdom
Prior art keywords
marker
march
recording layer
magnetic tapes
magnetizable material
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB1124573A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
EMI Ltd
Original Assignee
EMI Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by EMI Ltd filed Critical EMI Ltd
Priority to GB1124573A priority Critical patent/GB1403804A/en
Publication of GB1403804A publication Critical patent/GB1403804A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B27/00—Editing; Indexing; Addressing; Timing or synchronising; Monitoring; Measuring tape travel
    • G11B27/10—Indexing; Addressing; Timing or synchronising; Measuring tape travel
    • G11B27/19—Indexing; Addressing; Timing or synchronising; Measuring tape travel by using information detectable on the record carrier
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
    • G11B20/00086—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
    • G11B20/00086—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy
    • G11B20/00094—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy involving measures which result in a restriction to authorised record carriers
    • G11B20/00123—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy involving measures which result in a restriction to authorised record carriers the record carrier being identified by recognising some of its unique characteristics, e.g. a unique defect pattern serving as a physical signature of the record carrier
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
    • G11B20/00086—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy
    • G11B20/00572—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy involving measures which change the format of the recording medium
    • G11B20/00586—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy involving measures which change the format of the recording medium said format change concerning the physical format of the recording medium
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/62—Record carriers characterised by the selection of the material
    • G11B5/68—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent
    • G11B5/70—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer
    • G11B5/716—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by two or more magnetic layers
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/62—Record carriers characterised by the selection of the material
    • G11B5/68—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent
    • G11B5/70—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer
    • G11B5/716—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by two or more magnetic layers
    • G11B5/718—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by two or more magnetic layers at least one on each side of the base layer
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/74—Record carriers characterised by the form, e.g. sheet shaped to wrap around a drum
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/84—Processes or apparatus specially adapted for manufacturing record carriers
    • G11B5/855—Coating only part of a support with a magnetic layer

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Security & Cryptography (AREA)
  • Signal Processing (AREA)
  • Magnetic Record Carriers (AREA)

Abstract

1403804 Magnetic record tapes EMI Ltd 7 March 1974 [8 March 1973] 11245/73 Heading G5R A tape substrate carries on one surface a magnetic recording layer and on the other surface at least one marker comprising a region of magnetizable material of substantially higher coercivity than the recording layer. A marker may be a magnetized region of a continuous layer of magnetizable material or a discrete element of such material, e.g. a strip of adhesive splicing tape. Information may be magnetically recorded on a marker.
GB1124573A 1973-03-08 1973-03-08 Magnetic tapes Expired GB1403804A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB1124573A GB1403804A (en) 1973-03-08 1973-03-08 Magnetic tapes

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1124573A GB1403804A (en) 1973-03-08 1973-03-08 Magnetic tapes

Publications (1)

Publication Number Publication Date
GB1403804A true GB1403804A (en) 1975-08-28

Family

ID=9982678

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1124573A Expired GB1403804A (en) 1973-03-08 1973-03-08 Magnetic tapes

Country Status (1)

Country Link
GB (1) GB1403804A (en)

Similar Documents

Publication Publication Date Title
GB1481939A (en) Magnetic head assembly
JPS52102004A (en) Magnetic recording medium
DE3380677D1 (en) Magnetic recording and reproducing thin film head
GB1497891A (en) Magnetic recording media
GB1498165A (en) Magnetic recording media
JPS5597027A (en) Magnetic recording tape having epoxy substrate coating with polyester film back lining
JPS5690386A (en) Card
GB938095A (en) Information storage devices and method of making same
EP0220597A3 (en) Thin film vertical magnetic recording medium with a substrate, an intermediate layer and a magnetisable layer
GB1527283A (en) Tape leaders for recording tapes
GB1525292A (en) Identification of records
IT8019896A0 (en) EQUIPMENT FOR RECORDING AND/OR REPRODUCING SIGNALS ON MAGNETIC TAPE.
IT989964B (en) TAPE CASSETTE FOR RECORDING AND MAGNETIC PLAYBACK EQUIPMENT
GB1134319A (en) Heads for magnetic-recording apparatus
DE3068532D1 (en) Apparatus for recording and/or reproducing information on a magnetic tape
GB1403804A (en) Magnetic tapes
KR890005711A (en) Information signal recording device
US2747024A (en) Magnetic erase heads
JPS57164429A (en) Magnetic recording body
DE3575626D1 (en) TRACK-CONTROLLED MAGNETIC TAPE WITH CROSS-TRACK RECORDING.
GB1427731A (en) Magnetic recording media and to methods for their production
GB1213169A (en) Improvements in or relating to methods of magnetic recording
GB2054241B (en) Magnetic tape recording and playback
JPS5687217A (en) Vertical magnetization type magnetic head and its manufacture
SU602990A1 (en) Device for recording and erasing information on magnetic tape

Legal Events

Date Code Title Description
PS Patent sealed
PCNP Patent ceased through non-payment of renewal fee