ECMA
`
`EUROPEAN COMPUTER MANUFACTURERS ASSOCIATION
`
`STANDARD ECMA-120
`
`DATA INTERCHANGE ON 12,7 mm
`
`18-TRACK MAGNETIC TAPE CARTRIDGES
`
`3rd Edition - December 1993
`
`SONY Exhibit 1027
`SONY Exhibit 1027
`SONY v. FUJI
`SONYv. FUJI
`
`

`

`Free copies of this documentare available from ECMA,
`European Computer Manufacturers Association,
`114 Rue du Rhéne - CH-1204 Geneva (Switzerland)
`
`Internet: helpdesk@ecma.ch
`
`Phone: +41 22 735 3634 Fax: +41 22 786 52 31
`X.400: C=ch, A=arcom, P=ecma, O=genevanet,
`OU l=ecma, S=heipdesk
`
`

`

`EOCMA
`
`EUROPEAN COMPUTER MANUFACTURERS ASSOCIATION
`
`STANDARD ECMA-120
`
`DATA INTERCHANGEON 12,7 mm
`
`18-TRACK MAGNETIC TAPE CARTRIDGES
`
`3rd Edition - December 1993
`
`

`

`

`

`Brief History
`
`In 1985 ECMA decided to produce an ECMA Standard for a 12,7 mm, 18-Track Magnetic Tape Cartridge. Considerable
`work was invested in this project so that an urgently needed standard was developed rapidly and published in December
`1986.
`
`Upon request of ISO/TC97/SC11 this ECMA Standard has been contributed to ISO for further processing as draft
`International Standard DIS 9661 under the ISO fast-track procedure.
`
`The requirements for magnetic properties were defined in the first edition of Standard ECMA-120 by meansof new tests not
`requiring to relate the performance of the tape undertest to that of a Master Standard Reference Tape. Extensive work in
`several laboratories, specially in the USA, had shown in the meantime that these new tests presented more difficulties than
`originally assessed and that muchreliability and simplification could be achieved by reverting to the use of a Master Standard
`Reference Tape. Such a tape has been established at the National Institute for Standards and Technology (NIST) in
`Washington, as well as Secondary Standard Reference Tapes.
`
`As a consequence of these developments ISO DIS 9661 was reviewed accordingly and the original tests for the magnetic
`properties were replaced by tests based on the Reference Tape. A small number of numeric values, in particular of the
`dimensionsof the case, were also amended.
`
`A 2nd Edition of Standard ECMA-120 was developed to makeit technically identical with International Standard ISO 9661.
`
`Standard ECMA-152 is an extension of Standard ECMA-120 and has been accepted under the fast-track procedure as
`ISO/IEC 11559. The contents of this International Standard as well as comments raised during theletter ballot of DIS 11559
`have led to two Technical Corrigenda to ISO 9661 and some remaining comments. A new edition of ISO 9661 includes all
`these changes, is fully aligned with ISO/IEC 11559, and will be published as ISOMEC 9661:1994. This 3rd Edition of
`Standard ECMA-120is technically identical with International Standard ISO/IEC 9661:1994.
`
`Adopted as the 3rd Edition of ECMA-120 by the General Assembly of December 1993.
`
`

`

`

`

`Table of contents
`
`Section
`
`1 - General
`
`Scope
`
`Conformance
`
`References
`
`Definitions
`
`4.1
`
`4.2
`
`43
`
`4.4
`
`4.5
`
`46
`
`4.7
`
`48
`
`4.9
`
`4.10
`
`4.11
`
`4.12
`
`4.13
`
`4.14
`
`4.15
`
`4.16
`
`4.17
`
`4.18
`
`4.19
`
`4.20
`
`4.21
`
`4.22
`
`5.1
`
`5.2
`
`5,3
`
`5.4
`
`Average Signal Amplitude
`back surface
`
`Beginning of Tape (BOT)
`byte
`cartridge
`Cyclic Redundancy Check character
`data density
`Error Correcting Code
`flux transition position
`flux transition spacing
`magnetic tape
`Master Standard Reference Tape
`physical recording density
`Postamble
`
`Preamble
`
`Reference Field
`
`Secondary Standard Reference Tape
`Standard Reference Amplitude (SRA)
`Standard Reference Current
`
`Test Recording Current
`track
`
`Typical Field
`
`Environment and safety
`
`Cartridge/Tape testing environment
`Cartridge operation environment
`Cartridge storage environment
`Safety requirements
`
`5.4.1
`
`Safety
`
`Page
`
`WONNNNNNYNNNYNYBYNmmeet
`
`eoWWWwWWwWwW
`
`

`

`-li-
`
`5.4.2
`
`5.5
`
`Flammability
`
`Transportation
`
`Section 2 - Tape requirements
`
`6
`
`Characteristics of the tape
`
`6.1
`
`6.2
`6.3
`6.4
`6.5
`6.6
`
`6.7
`6.8
`6.9
`6.10
`
`Material
`
`Tape length
`Tape width
`Tape discontinuity
`Total thickness of tape
`Base material thickness
`
`Longitudinal curvature
`Out-of-plane distortions
`Cupping
`Dynamicfrictional characteristics
`
`6.10.1
`6.10.2
`
`Frictional drag between the recording surface and the tape back surface
`Frictional drag between the tape recording surface andferrite after environmental cycling
`
`6.11
`6.12
`6.13
`
`6.14
`6.15
`6.16
`6.17
`6.18
`
`6.18.1
`6.18.2
`6.18.3
`
`6.18.4
`
`6.18.5
`
`Coating adhesion
`Flexural rigidity
`Electrical resistance of coated surfaces
`
`Tape durability
`Inhibitor tape
`Tape abrasivity
`Pre-recording condition
`Magnetic recording characteristics
`
`Typical Field
`Signal amplitude
`Resolution
`
`Overwrite
`
`Narrow-BandSignal-to-Noise Ratio (NB-SNR)
`
`6.19
`
`Tape quality
`
`6.19.1
`6.19.2
`6.19.3
`
`Missing pulses
`Missing pulse zones
`Coincident missing pulse zones
`
`Section 3 - Cartridge requirements
`
`7
`
`Dimensional and mechanical characteristics of the cartridge
`
`71
`7.2
`73
`TA
`
`Overall dimensions(figures 4 to 6)
`Write-inhibit mechanism (figures 4 and 5)
`Labelarea ofthe rear side (figures 5 and 6)
`Label area ofthe top side (figure 5)
`
`oOwowoOmMmNAHNAAAIAAMAWnFfSFhbSSfF&LHHHHKSH
`
`—OoOo©&
`
`10
`
`10
`
`11
`
`11
`
`11
`
`12
`
`

`

`- ili -
`
`75
`
`7.6
`
`V7
`
`78
`
`79
`
`7.10
`
`711
`
`7.12
`
`- Case opening (figures 4, 5, 7 and 9)
`Locating notches (figures 7, 8 and 10)
`Locating areas (figure 7)
`Inside configuration of the case around the case opening (figures 7 and 11)
`Other external dimensionsof the case (figure 8)
`Central window(figure 7)
`Stacking ribs (figures 6 and 7)
`Flexibility of the case
`
`7.12.1
`
`7.12.2
`
`Requirements
`Procedure
`
`7.13
`
`Tape reel (figures 12 and 13)
`
`7.13.1
`
`7.13.2
`
`7.13.3
`
`7.13.4
`
`7.13.5
`
`7.13.6
`
`7.13.7
`
`7.14
`
`7.15
`
`7.16
`
`717
`
`7.18
`
`7.19
`
`7.20
`
`Locking mechanism (figure 13)
`Axis of rotation of the reel
`
`Metallic insert (figure 8)
`Toothed rim (figure 8)
`Hubofthe reel (figure 8)
`Relative positions
`Characteristics of the toothed rim (figure 12)
`
`Leaderblock (figure 15)
`Attachmentofthe tape to the leader block (figure 16)
`Latching mechanism (figure 17)
`Tape wind
`Wind tension
`
`Circumference ofthe tape reel
`Momentofinertia
`
`Section 4 - Recording requirements
`
`8
`
`Method of recording
`
`8.1
`8.2
`8.3
`8.4
`8.5
`8.6
`8.7
`
`8.8
`
`Physical recording density
`Bit cell length
`Averagebit cell length
`Long-term average bit cell length
`Short-term average bit cell length
`Rate of change
`Bit shift
`
`Total character skew
`
`8.9
`8.10
`
`Read signal amplitude
`Coincident missing pulses
`
`9
`
`Track format
`
`9.1
`
`9.2
`
`Numberoftracks
`
`Reference edge
`
`RRRRRRRRG&
`
`25
`
`26
`
`26
`
`26
`
`26
`
`26
`
`

`

`-~iv-
`
`9.3
`
`9.4
`
`9.5
`
`Track positions
`Track width
`
`Azimuth
`
`10
`
`Data format
`
`10.1
`
`Types of bytes
`
`10.1.1
`
`10.1.2
`
`Data bytes
`Pad bytes
`
`10.2
`
`10.3
`
`10.3.1
`
`10.3.2
`
`10.3.3
`
`10.3.4
`
`10.3.5
`
`10.3.6
`
`Frame
`
`Data Block
`
`Prefix
`
`Data Frames
`
`Residual Frame 1
`
`Residual Frame 2
`
`Summary of requirements for Residual Frames
`Suffix
`
`10.4
`
`Error Correcting Code (ECC)
`
`10.4.1
`
`10.4.2
`
`10.4.3
`
`Diagonal Redundancy Check (DRC)
`Vertical Redundancy Check (VRC)
`ECC Format
`
`26
`
`26
`
`27
`
`27
`
`27
`
`28
`
`28
`
`28
`
`28
`
`28
`
`29
`
`30
`
`31
`
`32
`
`32
`
`32
`
`33
`
`10.4.4
`
`Summary of ECC
`
`10.5
`
`10.6
`
`Recording of 8-bit bytes on the tape
`Recorded Data Block
`
`10.6.1
`
`10.6.2
`
`10.6.3
`
`10.6.4
`
`10.6.5
`
`Preamble
`
`Beginning of Data Mark (BDM)
`Resync Control Frame
`End of Data Mark (EDM)
`Postamble
`
`10.7
`
`Data density
`
`11
`
`Tape format
`
`11.1
`
`11.2
`
`41.3
`
`11.4
`
`11.4.1
`
`11.4.2
`
`11.5
`
`11.6
`
`11.6.1
`
`11.6.2
`
`Density Identification Burst
`ID Separator Burst
`Interblock Gaps
`Erase Gaps
`
`Normal Erase Gaps
`Elongated Erase Gaps
`
`Tape Marks
`Relationship between Interblock Gaps, Erase Gaps and Tape Marks
`
`Interblock Gap followed by a Tape Mark
`Tape Mark followed by an Interblock Gap
`
`33
`
`34
`
`35
`
`35
`
`35
`
`35
`
`35
`
`35
`
`35
`
`35
`
`36
`
`36
`
`37
`
`37
`
`37
`
`37
`
`37
`
`37
`
`38
`
`38
`
`38
`
`

`

`11.6.3
`
`11.6.4
`
`11.6.5
`
`11.7
`
`11.8
`
`11.8.1
`
`11.8.2
`
`Interblock Gap followed by an Erase Gap
`Erase Gap followed by an Interblock Gap
`Summaryof the relationship between Interblock Gaps, Erase Gaps and Tape Marks
`
`First and last recording on the tape
`Summary ofthe tape format
`
`Characteristics of recording other than recorded Data Blocks
`Arrangementof recording on the tape
`
`Annex A -
`
`Recommendationsfor transportation
`
`Annex B -
`
`Inhibitor tape
`
`Annex C -
`
`Tape abrasivity measurement procedure
`
`Annex D -
`
`Recommendations on tape durability
`
`Annex E -
`
`Pre-recording condition
`
`Annex F -
`
`Representation of 8-bit bytes by 9-bit patterns
`
`Annex G -
`
`Measurementofbit shift
`
`38
`
`38
`
`39
`
`39
`
`40
`
`40
`
`40
`
`41
`
`43
`
`45
`
`49
`
`51
`
`§3
`
`57
`
`

`

`

`

`Section 1 - General
`
`Scope
`This ECMA Standard specifies the physical and magnetic characteristics of a 12,7 mm wide, 18-track magnetic tape
`cartridge to enable interchangeability of such cartridges. It also specifies the quality of the recorded signals, the
`format and the recording method thus allowing, together with Standard ECMA-13 for Magnetic Tape Labelling, full
`data interchange by meansof such magnetic tape cartridges.
`
`Conformance
`
`A magnetic tape cartridge shall be in conformance with this Standard if it meets all mandatory requirements
`specified herein. The tape requirements shall be satisfied throughout the extent ofthe tape.
`
`References
`
`ECMA-6 (1991)
`
`7-Bit Coded Character Set
`
`ECMA-13 (1985)
`
`File Structure and Labelling of Magnetic Tapesfor Information Interchange
`
`ECMA-35 (1993)
`
`Code Extension Techniques
`
`ECMA-43 (1991)
`
`ISO 683-13:1986
`
`8-Bit Coded Character Set Structure and Rules
`
`Heat-treatable steels, alloy steels and free-cutting steels - Part 13: Wrought stainless
`Steels
`
`ISO 1302:1992
`
`Technical drawing - Method of indicating surface texture on drawings
`
`Definitions
`
`For the purposesofthis Standard, the following definitions apply.
`
`Average Signal Amplitude
`The average peak-to-peak value of the signal output of the read head measured over a minimum of 25,4 mm of
`tape exclusive of missing pulses,
`
`back surface
`
`The surface of the tape opposite the magnetic coating used to record data.
`
`Beginning of Tape (BOT)
`The point along the length of the magnetic tape indicated by the start of the Density Identification Burst.
`
`4.5
`
`4.6
`
`4.7
`
`4.8
`
`4.9
`
`byte
`An ordered set of eight bits acted upon as a unit and recorded as a 9-bit pattern.
`
`cartridge
`A container holding a supply reel of magnetic tape with an attached leader block.
`
`Cyclic Redundancy Check character
`A character represented by two bytes, placed at the end of a Data Block and used for error detection.
`
`data density
`The numberof 8-bit bytes stored per unit length of tape, expressed in bytes per millimetre.
`
`Error Correcting Code
`A mathematical procedure yielding bits used for the detection and correction oferrors.
`
`flux transition position
`That point which exhibits maximum free-space flux density normal to the tape surface.
`
`

`

`4.10
`
`4.11
`
`4.12
`
`4.13
`
`flux transition spacing
`The distance along a track between successive flux transitions.
`
`magnetic tape
`A tape which will accept and retain the magnetic signals intended for input, output and storage purposes on
`computers and associated equipment.
`
`Master Standard Reference Tape
`A tape selected as the standard for referencefield, signal amplitude, resolution and overwrite.
`
`NOTE 1
`
`A Master Standard Reference Tape has been established at the National Institute for Standards and Technology
`(NIST) for this Standard.
`
`physical recording density
`The number of recorded flux transitions per unit length of track, expressed in flux transitions per millimetre
`(ftpmm).
`
`4.14
`
`Postamble
`
`A repeated 9-bit pattern at the end of a recorded Data Block providing electronic synchronization when reading in
`the reverse direction.
`
`4.15
`
`Preamble
`
`A repeated 9-bit pattern at the beginning of a recorded Data Block providing electronic synchronization when
`Teading in the forward direction.
`
`4.16
`
`Reference Field
`
`The Typical Field of the Master Standard Reference Tape.
`
`4.17
`
`Secondary Standard Reference Tape
`A tape the performance of which is known andstated in relation to that of the Master Standard Reference Tape.
`NOTE 2
`
`Secondary Standard Reference Tapes have been developed at the National Institute for Standards and Technology
`(NIST) and are available from the NIST Office of Standard Reference Materials, Room 205, Building 202,
`National Institute of Standards and Technology, Gaithersburg, MA 20899, USA, under reference number SRM
`3202 until the year 2004.
`
`It is intended that these be usedfor calibrating tertiary reference tapes for use in routine calibration.
`
`4.18
`
`Standard Reference Amplitude (SRA)
`The Average Signal Amplitude from the Master Standard Reference Tape when it is recorded with the Test
`Recording Current on the NIST measurement system at 972 ftpmm.
`
`Traceability to the SRA is provided by the calibration factors supplied with each Secondary Standard Reference
`Tape.
`
`4.19
`
`Standard Reference Current
`
`The current that produces the Reference Field.
`
`4.20
`
`Test Recording Current
`The currentthatis 1,5 times the Standard Reference Current.
`
`4.21
`
`track
`
`A longitudinal area on the tape along which a series of magnetic signals may be recorded.
`
`

`

`4.22
`
`5
`
`5.1
`
`’ Typical Field
`In the plot of the Average Signal Amplitude against the recording field at the physical recording density of
`972 ftpmm, the minimum field that causes an Average Signal Amplitude equal to 85 % of the maximum Average
`Signal Amplitude.
`
`Environmentandsafety
`Unless otherwise stated, the conditions specified below refer to the ambient conditions in the test or computer room
`and not to those within the tape equipment.
`
`Cartridge/Tape testing environment
`Unless otherwise stated, tests and measurements made on the tape cartridge to check requirements of this
`Standard shall be carried out under the following conditions:
`
`temperature:
`relative humidity:
`conditioning period
`before testing:
`
`23 °C 42°C
`40 % to 60 %
`
`24 hours.
`
`5.2
`
`Cartridge operation environment
`Cartridges used for data interchange shall be capable of operating under the following conditions:
`
`temperature:
`relative humidity:
`wet bulb temperature:
`
`16 °C to 32 °C
`20 % to 80 %
`25 °C max,
`
`The average temperature ofthe air immediately surrounding the tape shall not exceed 40,5 °C.
`NOTE 3
`
`Localized tape temperatures in excess of49 °C may cause tape damage.
`
`Conditioning before operating: If a cartridge has been exposed during storage and/or transportation to conditions
`outside the above values,it shall be conditioned for a period of at least 24 hours.
`
`5.3
`
`Cartridge storage environment
`Cartridges used for data interchange shall be stored under the following conditions.
`
`temperature:
`relative humidity:
`wet bulb temperature:
`
`5 °C to 32 °C
`5 % to 80 %
`26 °C max.
`
`5.4
`
`5.4.1
`
`5.4.2
`
`5.5
`
`Safety requirements
`Safety
`The cartridge and its components shall not constitute any safety or health hazard when used in its intended
`manneror in any foreseeable misuse in an information processing system.
`
`Flammability
`The cartridge and its components shall be made from materials which, if ignited from a match flame, do not
`continue to burn in a still carbon dioxide atmosphere.
`
`Transportation
`This Standard does not specify parameters for the environment in which cartridges should be transported. Annex
`A gives some recommendations for transportation.
`
`

`

`Section 2 - Tape requirements
`
`6
`
`6.1
`
`Characteristics of the tape
`Material
`
`6.2
`
`6.3
`
`6.4
`
`6.5
`
`6.6
`
`6.7
`
`6.8
`
`6.9
`
`The tape shall consist of a base material (oriented polyethylene terephthalate film or its equivalent) coated on one
`side with a strong, yet flexible layer of ferromagnetic material dispersed in a suitable binder. The back surface of
`the tape mayalso be coated with a ferromagnetic or non-ferromagnetic material.
`
`Tape length
`The length of the tape shall notbe less than 165 m.
`
`Tape width
`The width of the tape shall be 12,650 mm + 0,025 mm. The width shall be measured across the tape from
`edge-to-edge whenthe tape is under a tension of less than 0,28 N.
`
`Tape discontinuity
`There shall be no discontinuities in the tape such as those produced bytape splicing or perforations.
`
`Total thickness of tape
`Thetotal thickness of the tape at any point shall be between 0,0259 mm and 0,0337 mm.
`
`Base material thickness
`
`The thickness of the base material shall be 0,0234 mm nominal.
`
`Longitudinal curvature
`Theradius of curvature of the edge of the tape shall not be less than 33 m.
`
`Procedure
`
`Allow a length of tape of 1 m to unroll and assumeits natural curvature on a flat smooth surface. Measure the
`deviation from a 1 m chord. The deviation shall not be greater than 3,8 mm. This deviation corresponds to the
`minimum radius of curvature of 33 m if measured overan arc ofcircle.
`
`Out-of-plane distortions
`All visual evidence of out-of-plane distortion shall be removed when the tape is subjected to a uniform tension of
`0,6 N. Out-of-plane distortions are local deformations which cause portions of the tape to deviate from the plane of
`the surface of the tape. Out-of-plane distortions are most readily observed when the tape is lying on a flat surface
`under no tension.
`
`Cupping
`The departure across the width of tape from a flat surface shall not exceed 0,3 mm.
`
`Procedure
`
`Cut a length oftape of 1,0 m + 0,1 m . Condition it for a minimum of 3 hours in the test environment by hanging
`it so that the coated surface is freely exposed to the test environment. From the centre portion of the conditioned
`tape cut a test piece of length 25 mm.Stand the test piece on its end in a cylinder which is at least 25 mm high
`with an inside diameter of 13,0 mm + 0,2 mm. With the cylinder standing on an optical comparator measure the
`cupping by aligning the edges of the sample to the reticle and determining the distance from the aligned edges to
`the corresponding surface of the test piece atits centre.
`
`6.10
`
`Dynamic frictional characteristics
`In the tests of 6.10.1 and 6.10.2 the specified forces of 1,0 N and 1,50 N, respectively, comprise both the force
`componentof the dynamic friction and the force of 0,64 N appliedto the test piece of tape.
`NOTE 4
`
`Particular attention should be given to keeping the surfaces clean.
`
`

`

`6.10.1 °
`
`Frictional drag between the recording surface and the tape back surface
`The force required to move the recording surface in relation to the back surface shall not be less than 1,0 N.
`
`Procedure
`
`a) Wrapatestpiece of tape around a 25,4 mm diametercircular mandrel with the back surface of the test
`piece facing outward.
`
`b)
`
`c)
`
`Place a secondtest piece of tape, with the recording surface facing in, aroundthe first test piece fora total
`angle of wrap of 90°.
`
`Apply a force of 0,64 N to one end of the outer test piece of tape. Secure its other end to a force gauge
`which is mounted on a motorizedlinear slide.
`
`d)_—Drivetheslide at a speed of 1 mm/s.
`
`6.10.2
`
`Frictional drag between the tape recording surface and ferrite after environmental cycling
`The force required to movethe tape at a point 1,34 m from the leader block of the cartridge shall not be greater
`than 1,50 N. The force required at a point 4,3 m from the junction of the tape with the cartridge hub shall not
`exceed the first force by more than a factor of 4.
`
`Procedure
`
`a)
`
`Windtape onto a spool hub of diameter 50 mm to an outside diameter of 97 mm with a winding tension
`of 2,2N+0,2N.
`
`b)_—_—Repeat the following twostepsfive times:
`
`a)
`
`b)
`
`Store for 48 hours at a temperature of 50 °C and a relative humidity of 10 % to 20 %.
`
`—Acclimatize in the testing environmentfor 2 hours and rewind with a tension of 2,2 N+ 0,2 N.
`
`¢)
`
`Condition the tape for 48 hours at a temperature of 30,5 °C anda relative humidity of 85 %. The tape
`shall remain in this environmentfor steps d) and e).
`
`d)=Apply a force of 0,64 N to one end of a test piece of tape of not more than 1 m, taken 1,34 m from the
`leader block. Pass the test piece over a ferrite rod of diameter 25,4 mm with the recording surface in
`contact with the rod for a total angle of wrap of 90°.
`
`The rod shall be made from the ferrite specified in annex C. It shall be polished to a roughness value R,
`of 0,05 pum (roughness grade N2, ISO 1302). Pull the other end ofthe test piece horizontally at 1 mm/s.
`
`e)
`
`Repeat step d) for a similar test piece taken 4,3 m from the junction of the tape with the cartridge hub.
`
`6.11
`
`Coating adhesion
`The force required to peel any part of the coating from the tape base material shall not be less than 1,5 N.
`
`Procedure
`
`a)
`
`Take a test piece of the tape approximately 380 mm long andscribe a line through the recording coating
`across the width of the tape 125 mm from one end.
`
`b)—Using a double-sided pressure sensitive tape, attach the full width of the test piece to a smooth metalplate,
`with the recording surface facing the plate, as shownin the figure below.
`
`c)
`
`d)
`
`Fold the test piece over 180°, attach the metal plate and the free end of the test piece to the jaws of a
`universal testing machine and set the speed of the jaw separation to 254 mm per min.
`
`Note the force at which any part of the coating first separates from the base material. If this is less than
`1,5 N,the test has failed. If the test piece peels away from the double-sided pressure sensitive tape before the
`force exceeds 1,5 N, an alternative type of double-sided pressure sensitive tape shall be used.
`
`e)—If the back surface of the tape is coated, repeat a) to d) for the back coating.
`
`

`

`Recording surface Scribedline Pressure-sensitive
`
`125 mm
`
`tape
`
`6.12
`
`Flexural rigidity
`The flexural rigidity of the tape in the longitudinal direction shall be between 0,06 N-mm2 and 0,16 N-mm2,
`
`Figure 1 - Coating adhesion
`
`Procedure
`
`Clamp a 180 mm test piece of tape in a universal testing machine, allowing a 100 mm separation between the
`machine jaws. Set the jaw separation speed at 5 mm per minute. Plot force against distance. Calculate the flexural
`rigidity using the slope of the curve between 2,2 N and 6,7 N bythe formula:
`
`dF /WT
`E =—
`bL/L
`
`3
`Tl=WT /12
`
`Flexural rigidity = EJ
`
`where :
`
`85F
`
`T
`
`Ww
`
`== changein force in N
`
`= measured thickness in mm
`
`= measured width in mm
`
`dL/L = changein length oftest piece between the jaws divided bythe original length between the jaws.
`Electrical resistance of coated surfaces
`
`6.13
`
`The electrical resistance of any square area of the recording surface shall be within the range:
`-
`105 Qto 5 x 108 Q for non-backcoated tapes;
`
`-
`
`10° Qto 5.x 10° Q for backcoated tapes,
`
`Theelectrical resistance of any backcoating shall be less than 10° Q.
`
`

`

`~ Procedure
`
`Condition a test piece of tape to the test environment for 24 hours. Position the test piece over two 24-carat
`gold-plated, semi-circular electrodes having a radius r = 25,4 mm andafinish ofat least N4, so that the recording
`surface is in contact with each electrode. These electrodes shall be placed parallel to the ground and parallel to
`eachother at a distance d = 12,7 mm between their centres. Apply a force F of 1,62 N to each endofthetest piece.
`Apply a d.c. voltage of 500 V + 10 V across the electrodes and measure the resulting current flow. From this
`value, determine the electrical resistance.
`
`Repeat for a total of five positions along the test piece and average the five resistance readings. For back-coated
`tape repeat the procedure with the backcoating in contact with the electrodes.
`
`F
`
`F
`
`Figure 2 - Position of test piece over two semi-circular electrodes
`
`When mounting the test piece, make sure that no conducting paths exist between the electrodes except that
`through the coating undertest.
`
`NOTE 5
`
`Particular attention should be given to keeping the surfaces clean.
`
`Tape durability
`This Standard does not specify parameters for assessing tape durability.
`
`However, a recommended procedure is described in annex D.
`
`Inhibitor tape
`This Standard does not specify parameters for assessing whetheror not a tape is an inhibitor tape.
`
`However, annex B gives further information on inhibitor tapes.
`
`Tape abrasivity
`Tape abrasivity is the tendency ofthe tape to wear the tape transport. The length of the wear pattern on a wear bar
`shall not exceed 56 pm when measured as specified in annex C.
`
`Pre-recording condition
`Prior to recording data or to testing, the tape shall have been erased using alternating magnetic fields of decaying
`levels (anhysteretic process) to ensure that the remanent magnetic moment of the recording surface does not
`exceed 20 % of the maximum remanent magnetic moment. Annex E specifies the method of measurement.
`
`In addition no low density transitions shall be present on the tape.
`
`Magnetic recording characteristics
`The magnetic recording characteristics shall be as defined by the testing requirements given below.
`
`6.14
`
`6.15
`
`6.16
`
`6.17
`
`6.18
`
`

`

`Whenperforming these tests, the output or resultant signal shall be measured on the samerelative pass for both a
`tape calibrated to the Master Standard Reference Tape and the tape undertest (read-while-write orfirst forward-
`read-pass) on the same equipment.
`
`The following conditions shall apply to the testing of all magnetic recording characteristics, unless otherwise
`stated:
`
`—
`
`—
`
`~
`
`—
`
`—
`
`tape condition
`
`tape speed
`
` read-track
`
`: pre-recording condition
`
`: not greater than 2,5 m/s
`
`: within the written track
`
`azimuth alignment
`
`‘ not greater than 6' between the mean write transitions and the read gap
`
` write-gap length
`
`21,4 um + 0,2 pm
`
`— write head saturation density
`
`:0,34T+0,03T
`
`—
`
`—
`
`tape tension
`
`:2,.2N+0,2N
`
`recording current
`
`: Test Recording Current
`
`6.18.1
`
`Typical Field
`The Typical Field of the tape shall be between 90 % and 110 % of the Reference Field.
`
`Traceability to the Reference Field is provided by the calibration factors supplied with each Secondary Standard
`Reference Tape.
`
`6.18.2
`
`Signal amplitude
`The Average Signal Amplitude at the physical recording density of 972 ftpmm shall be between 70 % and
`140 % of the SRA.
`
`Traceability to the Standard Reference Amplitude is provided by the calibration factors supplied with each
`Secondary Standard Reference Tape.
`
`6.18.3
`
`Resolution
`
`The ratio of the Average Signal Amplitude at the physical recording density of 1 458 ftpmm to that at the
`physical recording density of 972 ftpmm shall be between 80 % and 120 % of the sameratio for the Master
`Standard Reference Tape.
`
`Traceability to the resolution of the Master Standard Reference Tape is provided by the calibration factors
`supplied with each Secondary Standard Reference Tape.
`
`6.18.4
`
`Overwrite
`
`Overwrite is the ratio of the Average Signal Amplitude of the residual of the fundamental frequency of a tone
`pattern after being overwritten at 972 ftpmm to the Average Signal Amplitude of the 972 ftpmm signal. The
`Average Signal Amplitude of the tone pattern is the peak-to-peak amplitude of the sinusoidal signal with equal
`rms power.
`
`6.18.4.1
`
`Requirement
`The overwrite for the tape shall be less than 120 % of the overwrite for the Master Standard Reference Tape.
`
`Traceability to the overwrite of the Master Standard Reference Tape is provided by the calibration factors
`supplied with each Secondary Standard Reference Tape.
`
`Procedure
`
`Record a tone pattern which shall be the following sequenceof flux transitions:
`
`

`

`0
`
`0
`
`0
`
`0
`
`0
`
`1
`
`0
`
`0
`
`0
`
`0
`
`0
`
`a,
`
`|@
`
`where: a, = 1,029 pm
`a, = 0,514 pm
`
`Record a 972 ftpmm signal over the tone pattern. Measure the Average Signal Amplitude of the residual of
`the fundamental frequency of the tone pattern (one sixth of the frequency of the 972 ftpmm signal) and the
`Average Signal Amplitude of the 972 ftpmm signal. Both amplitude measurements should be made using
`suitable filters.
`
`6.18.5
`
`6.18.5.1
`
`Narrow-Band Signal-to-Noise Ratio (NB-SNR)
`The narrow-bandsignal-to-noise ratio is the Average Signal Amplitude rms power divided by the average
`integrated (side band) rms noise power, and is expressed in decibels.
`
`Requirement
`The NB-SNR ratio shall be equal to, or greater than, 30 dB when normalized to a track width of 410 tm.
`The normalization factor is dB(410) = dB(W) + 10 log 410/W, where W is the track width used when
`measuring dB(W).
`
`6.18.5.2
`
`Procedure
`
`The NB-SNR ratio shall be measured using a spectrum analyzer with a resolution bandwidth (RBW)of
`1 kHz and a video bandwidth (VBW) of 10 Hz. The tape speed shall be 762 mm/s for the frequencies
`specified below.
`
`The NB-SNR ratio shall be measured as follows:
`
`a)
`
`b)
`
`Measurethe read-signal amplitude of the 972 ftpmm signal, taking a minimum of 150 samples over a
`minimum length of tape of 46 m.
`
`On the next pass (read only) measure the rms noise power over the same section of tape and integrate
`the rms noise power (normalizing for the actual resolution bandwidth) over the range from 332 kHz to
`366 kHz.
`
`For other tape speedsall the frequencies shall be linearly scaled.
`
`6.19
`
`Tape quality
`The tape quality (including the effects of exposure to storage and transportation environments) is defined by the
`testing requirements given in the following clauses. The following conditions shall apply to all quality testing
`requirements:
`
`environment
`
`tape condition
`
`tape speed
`
`tead-track width
`
`: operating environment
`
`: pre-recording condition
`
`:2 m/s
`
`2410 pm
`
`physical recording density
`
`> 972 ftpmm
`
`write-gap length
`
`: 1,4 um + 0,2 wm
`
`azimuth alignment
`
`: not greater than 6' between the mean write transitions and the read gap
`
`write head saturation density
`
`0,34 T + 0,03 T
`
`recording current
`
`: Test Recording Current
`
`format
`
`tape tension
`
`: 18 tracks
`
`:2,2N+0,2N
`
`

`

`-10-
`
`6.19.1
`
`6.19.2
`
`6.19.3
`
`Missing pulses
`A missing pulse is a loss of read signal amplitude. A missing pulse exists when the base-to-peak read signal
`amplitude is 25 %, orless, of half the Average Signal Amplitude for the preceding 25,4 mm oftape.
`
`Missing pulse zones
`A missing pulse zone begins with a missing pulse and ends when 64 consecutive flux transitions are detected or
`a length of 1 mm oftape has been measured.
`The missing pulse zone rate shall be less than one in 8 x 10° flux transitions recorded.
`
`Coincident missing pulse zones
`There are two 9-track groups in the 18-track format. One group comprises the odd-numbered tracks, the other
`group comprises the even-numbered tracks. A simultaneous missing pulse zone condition on two or more tracks
`of a 9-track group is a coincident missing pulse zone.
`
`If a coincident missing pulse zone occurs at the same time in both groupsoftracks, it shall be considered as a
`single coincident missing pulse zone. Its length shall begin with the start of the earliest coincident missing
`pulse zone and terminate with the end of the latest coincident missing pulse zone.
`
`No 165 m length of tape shall have more than 12 coincident missing pulse zones.
`
`Nocoincident missing pulse zone shall exceed 50 mm.
`
`Section 3 - Cartridge requirements
`
`7
`
`Dimensional and mechanical characteristics of the cartridge
`Thecartridge shall consist of the following elements:
`a case;
`a reel for the magnetic tape;
`a magnetic tape wound on the hub ofthereel;
`a locking mechanism for the reel;
`a write-inhibit mechanism;
`a leader block;
`a latching mechanism for the leader block.
`
`Dimensional characteristics are specified for those parameters deemed mandatory for interchange and compatible use
`of the cartridge. Where there is freedom of design, only the functional characteristics of the elements described are
`indicated. In the figures a typical implementation is presented. Third angle projection is used.
`
`Where they are purely descriptive the dimensions are referred to three reference surfaces A, B and C forming a
`geometrical trihedral (see figure 3). Where the dimensions are related to the position of the cartridge in the drive,
`they may be referred to another surface of the cartridge. Figure 4 to 11 show the dimensions of the empty case.
`
`Figure 3
`
`Figure 4
`
`Figure 5
`
`Figure 6
`
`Figure 7
`
`Figure 8
`
`Figure 9
`
`Figure 10
`
`Figure 11
`
`Figure 12
`
`is a general view of the whole cartridge;
`
`showsthe front side of the case which lies in reference surface A;
`
`showsthe top side ofthe case;
`
`showstherear side ofthe case;
`
`showsthe bottom side of the case which lies in reference surface C;
`
`showsthe side of the case whichlies in reference surface B:
`
`showsan enlarged view of a part (case opening)offigure 4;
`
`showsan enlarged cross-section of a location notch;
`
`showsan enlarged cross-section of a detail of the opening of the case;
`
`showsan enlarged partial cross-section of the cartridge in hand;
`
`

`

`-1l-
`
`Figure 13
`
`Figure 14
`
`Figure 15
`
`Figure 16
`
`Figure 17
`
`showsthe samecross-section as figure 12 butof the cartridge in the drive;
`
`showsschematically the teeth of the toothed rim;
`
`shows two viewsand an enlarged cross-section of the leader block;
`
`showsthe fixation ofthe tape to the leader block, and
`
`showsthe leader block inserted in the case.
`
`7.1
`
`Overall dimensions (figures 4 to 6)
`The overall dimensionsof the case shall be
`
`i, = 125,00 mm + 0,32 mm
`L, = 109,00 mm + 0,32 mm
`+0,50 mm
`Ig = 24,50 mm “oo
`The corners ofthe case shall be rounded off as specified by
`
`r, = 3,00 m