ISO/IEC 15896:1999

INTERNATIONAL ISO/IEC
STANDARD 15896
First edition
1999-12-15
Information technology — Data
interchange on 12,7 mm 208-track
magnetic tape cartridges — DLT 5 format
Technologies de l'information — Échange de données sur cartouches
de bande magnétique de 12,7 mm, 208 pistes — Format DLT 5
Reference number
©
ISO/IEC 1999
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ii © ISO/IEC 1999 – All rights reserved

ISO/IEC ISO/IEC 15896:1999 (E)
Contents
Section 1 - General 1
1 Scope 1
2 Conformance 1
2.1 Magnetic tape cartridges 1
2.2 Generating systems 1
2.3 Receiving systems 1
3 Normative references 1
4 Definitions 1
4.1 Average Signal Amplitude 2
4.2 azimuth 2
4.3 back surface 2
4.4 Beginning-Of-Tape marker (BOT) 2
4.5 block 2
4.6 byte 2
4.7 cartridge 2
4.8 Cyclic Redundancy Check (CRC) character 2
4.9 Early Warning (EW) 2
4.10 Error-Detecting Code (EDC) 2
4.11 End-Of-Tape marker (EOT) 2
4.12 Entity 2
4.13 Error-Correcting Code (ECC) 2
4.14 Envelope 2
4.15 Envelope size 2
4.16 flux transition position 2
4.17 flux transition spacing 2
4.18 logical track 2
4.19 magnetic tape 2
4.20 Master Standard Reference Tape 2
4.21 object 2
4.22 page 2
4.23 physical recording density 2
4.24 physical track 2
4.25 Record 2
4.26 Reference Edge 2
4.27 Reference Field 2
4.28 Secondary Standard Reference Tape 2
4.29 Standard Reference Amplitude (SRA) 3
4.30 Standard Reference Current 3
iii
4.31 Test Recording Current 3
4.32 Typical Field 3
5 Conventions and notations 3
5.1 Representation of numbers 3
5.2 Dimensions 3
5.3 Names 3
5.4 Acronyms 3
6 Environment and safety 3
6.1 Cartridge and tape testing environment 3
6.2 Cartridge operating environment 4
6.3 Cartridge storage environment 4
6.4 Safety 4
6.4.1 Safeness 4
6.4.2 Flammability 4
6.5 Transportation 4
Section 2 - Requirements for the unrecorded tape 5
7 Mechanical and electrical requirements 5
7.1 Material 5
7.2 Tape length 5
7.3 Width 5
7.4 Total thickness 5
7.5 Discontinuity 5
7.6 Longitudinal curvature 5
7.6.1 Requirement 5
7.6.2 Procedure 5
7.7 Out-of-Plane distortions 5
7.8 Cupping 5
7.9 Roughness of the coating surfaces 5
7.9.1 Roughness of the back coating surface 5
7.9.2 Roughness of the magnetic coating surface 5
7.10 Coating adhesion 6
7.11 Layer-to-layer adhesion 6
7.11.1 Requirements 6
7.11.2 Procedure 6
7.12 Modulus of elasticity 7
7.12.1 Requirement 7
7.12.2 Procedure 7
7.13 Flexural rigidity 7
7.13.1 Requirement 7
7.13.2 Procedure 7
7.14 Tensile yield force 8
7.14.1 Procedure 8
7.15 Electrical resistance 8
7.15.1 Requirement 8
7.15.2 Procedure 8
7.16 Inhibitor tape 9
7.17 Abrasivity 9
7.17.1 Requirement 9
7.17.2 Procedure 9
7.18 Light transmittance of the tape and the leader 9
7.19 Coefficient of dynamic friction 9
7.19.1 Requirements 9
7.19.2 Procedure for the measurement of the friction between the magnetic surface and the back surface 10
iv
ISO/IEC     ISO/IEC 15896:1999 (E)
7.19.3 Procedure for the measurement of the friction between the magnetic surface or the back surface and calcium
titanate ceramic 10
8 Magnetic recording characteristics 10
8.1 Typical Field 11
8.2 Signal amplitude 11
8.3 Resolution 11
8.4 Overwrite 11
8.4.1 Requirement 11
8.5 Peak shift 11
8.5.1 Requirement 11
8.5.2 Procedure 11
9 Tape quality 12
9.1 Missing pulses 12
9.1.1 Requirement 12
9.2 Missing pulse zone 12
9.2.1 Requirement 12
9.3 Tape durability 12
Section 3 - Mechanical specifications of the tape cartridge 12
10 General 12
10.1 Bottom side and right side 13
10.2 Back side and left side 14
10.3 Tape reel 14
10.4 Tape leader 15
10.5 Front side 16
10.6 Operation of the cartridge 16
10.7 Tape winding 17
10.8 Moment of inertia 17
10.9 Material 18
Section 4 - Requirements for an interchanged tape 27
11 Method of recording 27
11.1 Physical recording density 27
11.2 Channel bit cell length 27
11.2.1 Average Channel bit cell length 27
11.2.2 Long-term average Channel bit cell length 27
11.2.3 Short-term average Channel bit cell length 27
11.3 Flux transition spacing 27
11.4 Read signal amplitude 27
11.5 Azimuth 28
11.6 Channel skew 28
12 Tape format 28
12.1 Reference Edge 28
12.2 Direction of recording 28
12.3 Tape layout 28
12.4 Calibration and Directory Area 28
12.4.1 Scratch Area 29
12.4.2 Guard Area G1 29
12.4.3 Calibration Tracks Area 29
12.4.4 Guard Area G2 30
12.4.5 Directory Area 30
12.4.6 Guard Area G3 30
12.5 Data Area 30
12.5.1 Physical tracks 31
v
12.5.2 Logical tracks 33
13 Data format 34
13.1 Data Bytes 34
13.2 Data Blocks 34
13.3 Types of Blocks 34
13.4 Entities 34
13.5 Envelopes 34
13.6 Block format 34
13.6.1 Preamble 35
13.6.2 Sync 35
13.6.3 Data Field 35
13.6.4 EDC 36
13.6.5 Control Field 1 (CF1) 37
13.6.6 Control Field 2 (CF2) 38
13.6.7 CRC 39
13.6.8 Postamble 39
14 Use of blocks 39
14.1 Data Blocks 39
14.2 Filler Blocks 39
14.3 End of Track Blocks (EOTR) 40
14.4 End of Data Blocks (EOD) 40
14.5 ECC Blocks 40
15 Format of Entities 40
16 Format of Envelopes 40
17 Error handling 40
Annexes
A - Measurement of light transmittance 41
B - Generation of the Data Block CRCs 44
C - ECC generation 45
D - Generation of page CRCs 48
E - Format of MAP entries 49
F - Format of Control Field 1 50
G - Format of Control Field 2 51
H - Recommendations for transportation 52
J - Inhibitor tape 53
K - Recommendations on tape durability 54
L - Handling guidelines 55
vi
ISO/IEC    ISO/IEC 15896:1999 (E)
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission)
form the specialized system for worldwide standardization. National bodies that are members of ISO or IEC
participate in the development of International Standards through technical committees established by the
respective organization to deal with particular fields of technical activity. ISO and IEC technical committees
collaborate in fields of mutual interest. Other international organizations, governmental and non-governmental, in
liaison with ISO and IEC, also take part in the work.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
In the field of information technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
Draft International Standards adopted by the joint technical committee are circulated to national bodies for voting.
Publication as an International Standard requires approval by at least 75% of the national bodies castinga vote.
Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of
patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
International Standard ISO/IEC 15896 was prepared by ECMA — European association for standardizing
information and communication systems (as ECMA-259) and was adopted, under a special “fast-track procedure”,
by Joint Technical Committee ISO/IEC JTC 1, Information technology, in parallel with its approval by national
bodies of ISO and IEC.
Annexes A toG form a normative part of this International Standard. Annexes H toL are for information only.
vii
Introduction
This International Standard constitutes a further development of the magnetic tape cartridge specified in International Standard
ISO/IEC 15307. The number of tracks is raised to 208. As a result a native capacity of 35 Gbytes or, with compressed data, of
typically at least 70 Gbytes is achieved.
viii
4.1 Average Signal Amplitude: The average peak-to-peak value of the output signal from the read head at the physical
recording density of 2 254 ftpmm measured over a minimum length of track of 25,4 mm, exclusive of missing pulses.
4.2 azimuth: The angular deviation, in degrees of arc, of the mean flux transition line of the recording made on a track
from the line normal to the Reference Edge.
4.3 back surface:
The surface of the tape opposite the magnetic coating which is used to record data.
4.4 Beginning-Of-Tape marker (BOT): A hole punched on the centreline of the tape towards the end nearest to the
leader.
4.5 block: A set of contiguous bytes recorded on a physical track and considered as a unit.
4.6 byte: An ordered set of bits acted upon as a unit.
Note - In this International Standard, all bytes are 8-bit bytes.
4.7 cartridge: A case containing a single supply reel of 12,7 mm wide magnetic tape with a leader attached at the outer
end.
4.8 Cyclic Redundancy Check (CRC) character: A 64-bit character, generated by a mathematical computation,
used for error detection.
4.9 Early Warning (EW): A signal generated by the drive indicating the approaching end of the recording area.
4.10 Error-Detecting Code (EDC): A mathematical computation yielding check bytes used for error detection.
4.11 End-Of-Tape marker (EOT): A hole punched on the centreline of the tape towards the end farthest from the
leader.
4.12 Entity: A group of twenty blocks treated as a logical unit and recorded on a logical track, except Filler Blocks ,if any.
4.13 Error-Correcting Code (ECC): A mathematical computation yielding check bytes used for the correction of
errors detected by the CRC and the EDC.
4.14 Envelope: A group of Entities.
4.15 Envelope size:
The number of Entities in an Envelope.
4.16 flux transition position: The point which exhibits the maximum free-space flux density normal to the tape surface.
4.17 flux transition spacing: The distance on the magnetic tape between successive flux transitions.
4.18 logical track: A group of four physical tracks that are written or read simultaneously.
4.19 magnetic tape: A tape that accepts and retains magnetic signals intended for input, output, and storage purposes on
computers and associated equipment.
4.20 Master Standard Reference Tape: A tape selected as the standard for Reference Field, signal amplitude,
resolution, peak shift, and overwrite characteristics.
Note - The Master Standard Reference Tape has been established by the Quantum Corporation.
4.21 object: A Record or a page of type Tape Mark.
4.22 page:
A logical division of a block.
4.23 physical recording density: The number of recorded flux transitions per unit length of track, expressed in flux
transitions per millimetre (ftpmm).
4.24 physical track: A longitudinal area on the tape along which a series of magnetic signals can be recorded.
4.25 Record: A collection of User Bytes, the number of which is determined by the host.
4.26 Reference Edge:
The bottom edge of the tape when viewing the magnetic coating of the tape with the BOT to the
left and the EOT to the right of the observer.
4.27 Reference Field: The Typical Field of the Master Standard Reference Tape.
4.28 Secondary Standard Reference Tape: A tape the characteristics of which are known and stated in relation to
those of the Master Standard Reference Tape.
Note - Secondary Standard Reference Tapes can be ordered under Reference "SSRT/DLT4"from Quantum Corporation, 333 South Street, Shrewsbury, Mass.
01545-4195, USA. It is intended that these be used for calibrating tertiary reference tapes for routine calibration.
In principle, these Secondary Standard Reference Tapes will be available for a period of 10 years from the publication of the first version of this International
Standard. However, this period may be changed to take into account the demand for such Secondary Standard Reference Tapes.
ISO/IEC  ISO/IEC 15896:1999 (E)
4.29 Standard Reference Amplitude (SRA): The Average Signal Amplitude from the Master Standard Reference
Tape when it is recorded with the Test Recording Current at 2 254 ftpmm.
4.30 Standard Reference Current: The current that produces the Reference Field.
4.31 Test Recording Current: The current that is 1,1 times the Standard Reference Current.
4.32 Typical Field: In the plot of the Average Signal Amplitude against the recording field at the physical recording
density of 2 254 ftpmm, the minimum field that causes an Average Signal Amplitude equal to 95 % of the maximum
Average Signal Amplitude.
5 Conventions and notations
5.1 Representation of numbers
The following conventions and notations apply in this International Standard, unless otherwise stated.
− A measured value is rounded off to the least significant digit of the corresponding specified value. It implies that a specified
value of 1,26 with a positive tolerance +0,01, and a negative tolerance -0,02 allows a range of measured values from 1,235
to 1,275.
− In each block and in each field the bytes shall be arranged with Byte 1, the least significant, first. Within each byte the bits
shall be arranged with Bit 1, the least significant, first and Bit 8, the most significant bit, last. This order applies to the data,
and to the input and output of the error-detecting and error-correcting codes, and to the cyclic redundancy characters.
− Letters and digits in parentheses represent numbers in hexadecimal notation.
− The setting of bits is denoted by ZERO or ONE.
− Numbers in binary notation and bit patterns are represented by strings of 0 and 1 shown with the most significant bit to the

left.
5.2 Dimensions
The dimensions in figure 1 to 4 are nominal dimensions. Unless otherwise stated, all dimensions in figures 8 to 23 are in
millimetres with a tolerance of ± 50 mm.
5.3 Names
The names of basic elements, e.g. specific fields, are written with a capital initial letter.
5.4 Acronyms
BOT Beginning of Tape
CF1 Control Field 1
CF2 Control Field 2
CRC Cyclic Redundancy Check (character)
CT1 Calibration Track 1
CT2 Calibration Track 2
ECC Error-Correcting Code
EDC Error-Detecting Code
EOD End of Data
EOT End of Tape
EOTR End of Track
EW Early Warning
RLL Run Length Limited
SRA Standard Reference Amplitude
6 Environment and safety
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 drive.
6.1 Cartridge and tape testing environment.
Unless otherwise stated, tests and measurements made on the cartridge and tape to check the requirements of this International
Standard shall be carried out under the following conditions:
− temperature: 23 °C ± 2 °C
− relative humidity: 40 % to 60 %
− conditioning before testing: 24 h
6.2 Cartridge operating environment
Cartridges used for data interchange shall be capable of operating under the following conditions:
− temperature: 10 °C to 40 °C
− relative humidity: 20 % to 80 %
− wet bulb temperature: 25 °C max.

Note - Localized tape temperatures in excess of 49 °C may cause tape damage.
If during storage and/or transportation a cartridge has been exposed to conditions outside the above values, it shall be
conditioned before use by exposure to the operating environment for a time equal to, or greater than, the time away from the
operating environment up to a maximum of 24 h. There shall be no deposit of moisture on or in the cartridge.
6.3 Cartridge storage environment
Cartridges shall be stored under the following conditions:
− temperature: 16 °C to 32 °C
− relative humidity: 20 % to 80 %
The stray magnetic field at any point on the tape shall not exceed 4000 A/m. There shall be no deposit of moisture on or in the
cartridge.
6.4 Safety
6.4.1 Safeness
The cartridge and its components shall not constitute any safety or health hazard when used in the intended manner, or through
any foreseeable misuse in an information processing system.
6.4.2 Flammability
The cartridge and its components shall be made from materials which, if ignited from a match flame, and when so ignited do
not continue to burn in a still carbon dioxide atmosphere.
6.5 Transportation
This International Standard does not specify parameters for the environment in which cartridges should be transported. Annex
H gives some recommendations for transportation.
ISO/IEC  ISO/IEC 15896:1999 (E)
Section 2 - Requirements for the unrecorded tape
7 Mechanical and electrical requirements
7.1 Material
The tape shall consist of a base material (oriented polyethylene terephthalate film or its equivalent) coated on one surface with a
strong yet flexible layer of ferromagnetic material dispersed in a suitable binder. The other surface of the tape shall be coated
with a non-ferromagnetic conductive coating.
7.2 Tape length
The length of the tape from the leader splice to the hub shall be 557 m ± 5 m.
7.3 Width
The width of the tape shall be 12,649 mm ± 0,010 mm.
The width shall be measured across the tape from edge to edge when the tape is under a tension of less than 0,28 N.
7.4 Total thickness
The total thickness of the magnetic tape at any point shall be between 8,3 μm and 9,3 μm.
7.5 Discontinuity
There shall be no discontinuities in the tape between the BOT and EOT such as those produced by tape splicing or perforations.
7.6 Longitudinal curvature
The longitudinal curvature is measured as the departure of the Reference Edge of the tape from a straight line along the
longitudinal dimension of the tape in the plane of the tape surface.
7.6.1 Requirement
Any deviation of the Reference Edge from a straight line shall be continuous and shall not exceed 0,076 mm within any 229
mm length of tape.
7.6.2 Procedure
Measure at a tension of 1,39 N ± 0,28 N in a test fixture equipped with two guides spaced at 229 mm. The two guides shall be
spring-loaded to position the Reference Edge of the tape against two edge control surfaces. Measure the maximum deviation of
the Reference Edge of the tape from the line drawn between the two control surfaces.
7.7 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.
7.8 Cupping
The departure across the width of the tape from a flat surface shall not exceed 2,54 mm.
Cut a 1,0 m ± 0,1 m length of tape. Condition it for a minimum of 3 h in the test environment by hanging it so that both surfaces
are freely exposed to the test environment. From the centre portion of the conditioned tape cut a test piece of approximately
25 mm length. 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 test piece to
the reticle and determining the distance from the aligned edges to the corresponding surface of the test piece at its centre.
7.9 Roughness of the coating surfaces
7.9.1 Roughness of the back coating surface
The back coating surface shall have an arithmetic average roughness R between 0,003 µm and 0,018 µm (ISO 1302:N 2). This
a
measurement shall be made using a contacting stylus of radius 12,5 µm with a 20 mg load, and a 254 µm cut-off range.
7.9.2 Roughness of the magnetic coating surface
The magnetic coating surface shall have an arithmetic average roughness R between 0,003 µm and 0,008 µm (ISO 1302: N 3).
a
For this measurement, the contacting stylus radius shall be 12,5 µm with a 20 mg load, and a 254 µm cut-off range.
7.10 Coating adhesion
The force required to peel any part of the coating from the tape base material shall not be less than 0,4 N.
Procedure
i. Take a test piece of the tape approximately 380 mm long and scribe a line through the recording coating across the width of
the tape 125 mm from one end.
ii. Using a double-sided pressure sensitive tape, attach the full width of the test piece to a smooth metal plate, with the
magnetic coating (recording surface) facing the plate, as shown in figure 1.
iii. Fold the test piece over 180°, adjacent to, and parallel with, the scribed line. 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.
iv. Note the force at which any part of the coating first separates from the base material. If this is less than 0,4 N, the tape has
failed the test. If the test piece peels away from the double-sided pressure sensitive tape before the force exceeds 0,4 N, an
alternative type of double-sided pressure sensitive tape shall be used.
v. Repeat i) to iv) for the back coating.
Figure 1 - Measurement of the coating adhesion
7.11 Layer-to-layer adhesion
Layer-to-layer adhesion refers to the tendency of a layer, when held in close proximity to the adjacent layer, to bond itself to an
adjacent layer so that free and smooth separation of the layers is difficult.
7.11.1 Requirements
There shall be no evidence of delamination or other damage to the coatings.
7.11.2 Procedure
i. Fasten one end of a 914 mm length of tape, magnetic coating inwards, to a horizontally mounted stainless steel cylinder with
a low cold-flow adhesive material.
ii. The dimensions of the cylinder shall be:
- diameter: 12,7 mm
- length: 102 mm
iii. Attach a mass of 1 000 g to the opposite end of the tape.
iv. Attach, 25,4 mm above the mass, a narrow strip of double-sided adhesive tape to the magnetic coating.
v. Slowly rotate the cylinder, so that the tape winds uniformly around it into a compact and even roll. The double-sided tape
secures the end and prevents unwinding when the mass is removed.
vi. The cylinder with the tape shall then be exposed to the following temperature and humidity cycle:
ISO/IEC  ISO/IEC 15896:1999 (E)
Time Temperature RH
16 h to 18 h 54 °C 85 %
4 h 54 °C 10 % or less
1 h to 2 h 21 °C 45 %
vii.Open the end of the roll and remove the double-sided adhesive tape.
viii.Release the free end of the tape.
ix. The outer one or two wraps shall spring loose without adhesion.
x. Hold the free end of the tape and allow the cylinder to fall, thereby unwinding the tape.
xi. The tape shall show no coating delamination, except for the 51 mm of tape nearest to the cylinder.
Figure 2 - Measurement of layer-to-layer adhesion
7.12 Modulus of elasticity
The modulus of elasticity (Young's modulus) is the ratio of stress to strain in the longitudinal direction.
7.12.1 Requirement
2 2
The modulus of elasticity shall be between 4 900 N/mm and 11 700 N/mm .
7.12.2 Procedure
Clamp a test piece of tape at least 178 mm in length with an initial 102 mm separation between the jaws of a universal testing
machine with a nominal crosshead speed of 3 mm per minute. Calculate the modulus using the chord of the curve between the
force at 0 % and 1 % elongation.
7.13 Flexural rigidity
Flexural rigidity is the ability of the tape to resist bending in the longitudinal direction.
7.13.1 Requirement
-7 -7
The flexural rigidity of the tape in the longitudinal direction shall be between 2 x 10 N ⋅ mm and 8 x 10 N ⋅ mm.
7.13.2 Procedure
Calculate the flexural rigidity D from the following equation:
Et×
D = ×−()1 υ
where:
E = modulus of elasticity obtained from 7.12
t = measured thickness of the tape in mm
ν = Poisson's ratio, set to 0,33
7.14 Tensile yield force
The tensile yield force required to elongate the test piece by 3 % shall not be less than 9,6 N.
7.14.1 Procedure
Use a static-weighing-constant-rate-of-grip separation tester capable of indicating the load with an accuracy of 2 %. Clamp a
test piece of tape at least 178 mm long with an initial 102 mm separation between the jaws. Elongate the test piece at a rate of
51 mm per minute until a minimum elongation of 10 % is reached. The force required to produce an elongation of 3 % is the
tensile yield force.
7.15 Electrical resistance
7.15.1 Requirement
The electrical resistance of any square area of the magnetic coating shall
− be greater than 5 x 10 Ω
− not exceed 50 x 10 Ω
The electrical resistance of any square area of the back coating shall
− not exceed 100 x 10 Ω
7.15.2 Procedure
Condition a test piece of tape in the test environment for 24 h. Position the test piece over two 24-carat gold-plated, semi-
circular electrodes having a radius r = 25,4 mm and a finish of at 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 each other at a distance d = 12,7 mm between
their centres. Apply a force F of 1,62 N to each end of the test piece. Apply a d.c. voltage of 100 V ± 10 V across the
electrodes and measure the resulting current flow. From this value, determine the electrical resistance.
Repeat for a total of 5 positions along the test piece and average the 5 resistance readings. For the back coating repeat the
procedure with the back surface in contact with the electrodes.
r r
d
FF
Figure 3 - Measurement of electrical resistance
When mounting the test piece, make sure that no conducting paths exist between the electrodes except that through the coating
under test.
ISO/IEC  ISO/IEC 15896:1999 (E)
Note - Particular attention should be given to keeping the surfaces clean.
7.16 Inhibitor tape
This Standard does not specify parameters for assessing whether or not a tape is an inhibitor tape. However, annex J gives
further information on inhibitor tapes.
7.17 Abrasivity
Tape abrasivity is the tendency of the magnetic coating to wear the magnetic heads.
7.17.1 Requirement
The depth of the wear pattern in a ferrite wear bar shall be less than 1,27 µm.
7.17.2 Procedure
A test piece 61 m in length shall be passed for 100 passes (50 cycles) over a rectangular bar of manganese zinc ferrite. The bar
shall be 0,3 mm wide and its top surface shall be rounded off with a radius r = 5 mm. The tape speed shall be 2,54 m/s, the
tension shall be nominally 1,3 N and the wrap angle shall be 12°. The wear depth is measured with a profilometer across the
width of the tape path.
Note - Manganese zinc ferrite should be available from Philips Ceramic Division in Saugerties (NY) under order part number 3H7.
Figure 4 - Measurement of abrasivity (not to scale)
7.18 Light transmittance of the tape and the leader
The light transmittance of the tape and the leader shall be less than 5 % when measured according to the method specified in
annex A.
7.19 Coefficient of dynamic friction
The coefficient of dynamic friction is measured between the surfaces of the tape, and calcium titanate ceramic.
7.19.1 Requirements
Between the magnetic surface and the back surface : greater than 0,15
Between the magnetic surface and other surfaces: 0,05 to 0,35
Between the back surface and calcium titanate: 0,05 to 0,20
7.19.2 Procedure for the measurement of the friction between the magnetic surface and the back surface
i. Wrap a first piece of tape around a calcium titanate ceramic cylinder (R = 0,05 μm) of diameter 25,4 mm and wrap it with
a
a total wrap angle of more than 90° with the back surface outwards.
ii. Wrap a second test piece, with the magnetic surface inwards, around the first test piece with a total wrap angle of 90°.

iii. Exert on one end of the outer test piece a force of F = 0,64 N.

iv. Attach the other end to a force gauge mounted on a linear slide.
v. Drive the slide at a speed of 1 mm/s, measure the force F required.
vi. Calculate the coefficient of dynamic friction γ from the equation
F 1
γ=×
ln( )
F π
where π is the value of the wrap angle in radians.
7.19.3 Procedure for the measurement of the friction between the magnetic surface or the back surface and calcium
titanate ceramic
i. Wrap a piece of tape around a calcium titanate ceramic cylinder (R = 0,05 μm) of diameter 25,4 mm and wrap it with a
a
total wrap angle of 90° with the magnetic surface or the back surface, as appropriate, inwards.
ii. Exert on one end of the test piece a force of F = 0,64 N.
iii. Attach the other end to a force gauge mounted on a linear slide.
iv. Drive the slide at a speed of 1 mm/s, measure the force F required.
v. Calculate the coefficient of dynamic friction γ from the equation
F 1
γ=×ln
( )
F π
where π is the value of the wrap angle in radians.
Note - Calcium titanate ceramic should be available from Philips Ceramic Division in Saugerties (NY) under order part Ca Ti.
8 Magnetic recording characteristics
The magnetic recording characteristics shall be defined by testing the requirements given below.
When performing the tests, the output or resultant signal shall be measured on the same relative pass for both a tape calibrated
to the Master Standard Reference Tape and the tape under test (read-while-write, or on equipment without read-while-write
capability, on the first forward-read-pass) on the same equipment.
The following conditions shall apply to the testing of all magnetic recording characteristics, unless otherwise noted.
− Tape condition: a.c. erased to 2 % or less of the Average Signal Amplitude
− Tape speed: 4,06 m/s ± 0,05 m/s
− Read track: within the written track

− Gap alignment: the read gap and the write gap to be parallel within 38,1 μm
− Write gap length: 0,89 µm ± 0,18 µm

− Write gap width: 0,216 mm ± 0,010 mm
− Read gap length: 0,18 µm ± 0,05 µm
− Read gap width: 43 µm ± 5 μm

− Tape tension: 0,79 N ± 0,08 N
ISO/IEC  ISO/IEC 15896:1999 (E)
− Recording current: Test Recording Current

− Physical recording densities: 2f = 2 254 ftpmm ± 44 ftpmm, corresponding to 4,58 MHz ± 2 %
1f = 1 127 ftpmm ± 22 ftpmm, corresponding to 2,29 MHz ± 2 %
− Bandwidth of the read
amplifier: 10,0 MHz
8.1 Typical Field
The Typical Field shall be between 75 % and 125 % of the Reference Field.
Traceability to the Reference Field is provided by the calibration factors supplied with each Secondary Standard Reference
Tape.
8.2 Signal amplitude
The Average Signal Amplitude shall be between 85 % and 115 % of the SRA.
Traceability to the SRA is provided by the calibration factors supplied with each Secondary Standard Reference Tape.
8.3 Resolution
The ratio of the average signal amplitude at the physical recording density of 2 254 ftpmm to that at the physical recording
density of 1 127 ftpmm shall be between 90 % and 120 % of the same ratio 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.
8.4 Overwrite
Overwrite is the ratio of the residual signal of the average signal amplitude recorded at 1 127 ftpmm after being overwritten at 2
254 ftpmm to the average signal amplitude of the 1 127 ftpmm signal.
8.4.1 Requirement
The overwrite for the tape shall be less than 110 % 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.
8.5 Peak shift
Peak shift is measured as the time displacement from nominal of the ONEs transitions in the recorded pattern 110110110.with
a bit cell length of 0,148 µm.
8.5.1 Requirement
For a peak shift ratio of n % for the Master Standard Reference Tape, the measured peak shift ratio shall be between (n-2) %
and (n+2) %.
Traceability to the peak shift ratio of the Master Standard Reference Tape is provided by the calibration factors supplied with
each Secondary Standard Reference Tape.
8.5.2 Procedure
The time interval measurements shall be averaged over 250 ONE-ONE-ZERO patterns taken at a sampling rate of 96 times 2f.
The time between adjacent peaks in the ONE-ONE interval is denoted as t
. The time between the last ONE in the ONE-ONE
interval to the last ONE in the following ONE-ONE interval is denoted as t .
3tt�
Peak shift� �100%
2t
Figure 5 - Measurement of peak shift
9 Tape quality
9.1 Missing pulses
A missing pulse is a loss of read signal amplitude. When a base-to-peak read signal amplitude is less than 35 % of half the
Average Signal Amplitude (see 8.2) for the preceding 25,4 mm of track, then these 25,4 mm constitute a missing pulse. This
measurement shall be carried out in steps of 25,4 mm of track.
9.1.1 Requirement
The average missing pulse rate shall be less than 20 missing pulses for any recorded length of track of 100 m.
9.2 Missing pulse zone
A missing pulse zone is a sequence of missing pulses exceeding 100 mm.
9.2.1 Requirement
Missing pulse zones shall not occur.
9.3 Tape durability
This International Standard does not specify parameters for assessing tape durability. However, a recommended procedure is
described in annex K.
Section 3 - Mechanical specifications of the tape cartridge
10 General
The tape cartridge shall consist of the following elements
− a case
− a reel for the magnetic tape
− a locking mechanism for the reel
− a magnetic tape wound on the hub of the reel
− a write-inhibit mechanism
− a tape leader
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.
Where they are purely descriptive the dimensions are referred to three reference planes A, B, and C forming a geometrical
trihedral. Where the dimensions are related to the position of the cartridge in the drive, they may be referenced to another
surface of the cartridge.
In the enclosed drawings a typical implementation is represented.
Figure 6 shows a general view of the cartridge.
Figure 7 shows the reference planes A, B, C.
Figure 8 shows the bottom side of the cartridge.
Figure 9 shows the right side of the cartridge.
Figure 10 shows the back side of the cartridge.
ISO/IEC  ISO/IEC 15896:1999 (E)
Figure 11 shows the left side of the cartridge.
Figure 12 shows a partial cross-section of the cartridge in locked position.
Figure 13 shows a partial cross-section of the cartridge in operating position.
Figure 14 shows the leader-to-tape connection.
Figure 15 shows the splice of the leader-to-tape connection.
Figure 16 shows the leader.
Figure 17 shows the front side of the cartridge.
Figure 18 shows the back side of the cartridge with partial cut.
Figure 19 shows the top side of the cartridge with partial cut and the door open.
Figure 6 shows a general view of the cartridge. When it is not in the operating position, the reel of magnetic tape is locked and
cannot rotate. When loaded into the drive, the back side is introduced first and the front side remains visible during operation.
During the loading process the tape reel is unlocked and the position of the cartridge within the drive is fixed by elements of the
drive engaging with corresponding elements of the case.
The position of the case relative to the reference planes A, B and C is shown in figure 7. The top side lies in reference plane A,
the right side lies in reference plane B and the back side lies in reference plane C.
10.1 Bottom side and right side (figures 8 and 9)
The overall dimensions of the cartridge shall be
l = 105,79 mm ± 0,20 mm
l = 105,41 mm ± 0,20 mm
l = 25,40 mm ± 0,25 mm
The bottom side shall have a window the dimensions and the position of which shall be defined by
l = 6,25 mm ± 0,10 mm
l = 4,85 mm ± 0,05 mm
l = 84,07 mm ± 0,20 mm
l = 3,81 mm ± 0,05 mm
This window allows one of the fingers of the drive to penetrate into the case for partially unlocking the reel of tape (see 10.6).
A positioning hole on the bottom side and a guiding notch, followed by a positioning notch in the right side determine the
position of the cartridge in the drive.
The dimensions and the position of the positioning hole shall be defined by
l = 21,59 mm ± 0,10 mm
+ 0,13 mm
l = 4,45 mm
- 0,00 mm
l = 2,79 mm ± 0,05 mm
l = 44,58 mm ± 0,20 mm
The dimensions and the position of the positioning notch shall be defined by
l = 5,56 mm ± 0,10 mm
l = 33,30 mm ± 0,20 mm
l = 5,08 mm ± 0,10 mm
h = 9,02 mm ± 0,10 mm
a = 14° ± 30'
The dimensions and the position of the guiding notch shall be defined by
l = 8,59 mm ± 0,10 mm
l = 24,64 mm ± 0,10 mm
l = 1,50 mm ± 0,05 mm
a = 45° ± 30'
a = 14° ± 30'
The right side shall have an indicator connected to the manually operable write-inhibit switch described in 10.5. The
dimensions and the position of this indicator shall be defined by
l = 8,64 mm ± 0,10 mm
l = 5,08 mm ± 0,10 mm
l = 86,11 mm ± 0,20 mm
l = 10,16 mm ± 0,10 mm
Writing is enabled when the surface of the indicator is substantially flush with the cartridge wall. When this surface is recessed
by at least 5,1 mm writing is inhibited. When a force of up to 1,0 N is exerted perpendicularly on the centre of the surface of the
indicator, it shall not recede by more than 0,5 mm from reference plane B.
10.2 Back side and left side (figures 10 and 11)
The back side shall have a window the dimensions and position of which shall be
l = 8,76 mm ± 0,10 mm
l = 4,25 mm ± 0,10 mm
l = 4,45 mm ± 0,10 mm
l = 8,89 mm ± 0,10 mm
This window allows a further finger of the drive to penetrate into the case to finally unlock the reel of tape (see also 10.6).
A door shall be rotatably mounted at the corner of the back side and the left side. It is described in 10.6.
The left side shall have two edges the positions and lengths of which shall be
l = 61,47 mm ± 0,20 mm
+ 0,13 mm
l = 9,65 mm
- 0,00 mm
l = 41,9 mm ± 0,20 mm
+ 0,18 mm
l = 6,18 mm
- 0,00 mm
10.3 Tape reel (figures 8, 12 and 13)
The bottom side of the case shall have a circular window through which the drive spindle contacts the hub of the reel and
transmits torque. The diameter of this window shall be
d = 35,05 mm ± 0,08 mm
The position of its centre shall be defined by
l = 50,42 mm ± 0,31 mm
l = 52,83 mm ± 0,10 mm
The interface between the spindle and the hub is provided by 48 evenly spaced teeth in the hub. In the non-operating position,
the surface of the hub shall be recessed from the outside surface of the case by
l = 0,38 mm ± 0,05 mm
The tooth profile consists of straight flanks. The envelope dimensions of the teeth shall be
d = 23,88 mm ± 0,13 mm
ISO/IEC  ISO/IEC 15896:1999 (E)
d = 29,21 mm ± 0,13 mm
d = 34,29 mm ± 0,13 mm
a = 22° ± 30'
a = 15° ± 30'
where d is the pitch diameter of the teeth.
In the operating position the surface of the hub shall be at a distance
l = 23,55 mm ± 0,10 mm
from reference plane A.
10.4 Tape leader (figures 14, 15 and 16)
The positions of the BOT and EOT relative to the leader/tape connection and to the physical end of the tape shall be as follows.
The BOT shall be at a distance
l = 13 260 mm ± 150 mm
from the leader/tape connection.
The EOT shall be at a distance
l = 2 540 mm ± 610 mm
from the physical end of the tape, which is fixed to the hub of the reel. Both the BOT hole and EOT hole shall have a diameter
d = 4,78 mm ± 0,10 mm
Figure 15 shows the relative positions of the tape, the leader and the splice tape. They shall be defined by
11,81 mm min.
l =
20,32 mm max.
l = 0,25 mm max.
l = 0,41 mm max.
l = 0,00 mm min.
l = 0,20 mm max.
Dimensions l , l and l are related to, and depend on, each other. Dimension l expresses the requirement that the splice
34 35 36 35
tape shall in no case extend beyond the edges of either the tape or the leader.
There shall be no yield of the splice when a force of 22,2 N max. is applied in longitudinal direction across the splice.
Figure 16 shows the dimensions of the leader which shall be
+ 0,00 mm
l = 12,65 mm
- 0,10 mm
l = 309,63 mm ± 0,30 mm
l = 130,96 mm ± 0,10 mm
l = 22,35 mm ± 0,10 mm
l= 8,13 mm ± 0,10 mm
l = 3,05 mm ± 0,05 mm
l = 2,95 mm ± 0,05 mm
+ 0,13 mm
l = 2,79 mm
- 0,00 mm
l = 18,54 mm ± 0,10 mm
l = 8,69 mm ± 0,10 mm
l = 5,89 mm ± 0,10 mm
l = 6,33 mm ± 0,10 mm
l = 3,40 mm ± 0,05 mm
l = 3,73 mm ± 0,05 mm
l = 5,00 mm ± 0,05 mm
l = 7,47 mm ± 0,10 mm
l = 6,86 mm ± 0,10 mm
l = 8,15 mm ± 0,10 mm
l = 2,24 mm ± 0,10 mm
l = 3,40 mm ± 0,05 mm
l = 6,325 mm ± 0,001 mm
r = 4,98 mm ± 0,05 mm
r = 15,01 mm ± 0,10 mm
r = 10,21 mm ± 0,10 mm
r = 3,40 mm ± 0,05 mm
r = 4,00 mm ± 0,01 mm
a = 5° ± 30'
a = 15° ± 30'
a = 60° ± 30'
The design of the leader is explained in 10.6.
10.5 Front side (figure 17)
The manually operable write-inhibit switch shall have the dimensions
+ 0,00 mm
l = 18,29 mm
- 0,20 mm
l = 26,60 mm ± 0,20 mm
This switch shall have a detent at its two end positions with a force suitable to meet the requirement of the write-inhibit
indicator in the right side of the case with which it shall be connected. The actual force depends on the design of the
connection.
The front side shall have a slot intended for labels. The dimensions of this slot shall be
l = 54,40 mm ± 0,20 mm
l = 18,40 mm ± 0,20 mm
l = 21,40 mm ± 0,20 mm
l = 0,76 mm ± 0,10 mm
10.6 Operation of the cartridge (figures 18 and 19)
When the cartridge is introduced into the drive, the sequence of events is as follows.
i. The door shall have a movable lock the lower edge of which shall be at a distance

l = 14,50 mm ± 0,20 mm
ISO/IEC  ISO/IEC 15896:1999 (E)
from reference plane A. A cam of the drive raises this lock in order to unlock the door which shall be unlocked when the
edge is raised by 1,0 mm min.
The door is then opened 90° by the drive. It shall be able to rotate further up to 105°. In the open position of the door the
whole back side shall be accessible except the part limited by
l = 35,79 mm ± 0,20 mm.
In this position the space along the left side that is delimited by
l = 3,40 mm ± 0,05 mm
shall be free for a drive element to contact the edge defined by l and l (see figure 11).
26 27
ii. A finger of the drive penetrates into the case through the window defined by l to l (see figure 10) to partially unlock the
22 25
reel. The corresponding part of the locking mechanism shall not require a penetration other than 8 mm ± 1 mm nor a force
other than 3,3 N ± 0,4 N to be actuated.
iii. When the cartridg
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