ISO/IEC 1864:1992

INTERNATIONAL
STANDARD
1864
Fourth edition
1992-06-15
Information technology - Unrecorded 12,7 mm
(0,5 in) wide magnetic tape for information
interchange - 32 ftpmm (800 ftpi), NRZI,
126 ftpmm (3 200 ftpi) Phase encoded and
356 ftpmm (9 042 ftpi), NRZI
Technologie de I’informafion - Bande magnetique vierge de 12,7 mm
(0,5 in) de /arge, pour I’khange d’infonnation - 32 ftpmm (800 ftpi),
NRZI, 126 ftpmm (3 200 ftpi) par codage de phase et 356 ftpmm
(9 042 ftpi), NRZI
Reference number
ISO/IEC 1864: 1992(E)

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ISO/IEC 1864:1992(E)
Foreword
ISO (the International Organization for Standardization) and IEC (the In-
ternational 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 com-
mittees collaborate in fields of mutual interest. Other international or-
ganizations, governmental and non-governmental, in liaison with ISO
and IEC, also take patt in the work.
In the field of information technology, ISO and IEC have established a
joint technical committee, ISOAEC JTC 1. Draft International Standards
adopted by the joint technical committee are circulated to national bod-
ies for voting. Publication as an International Standard requires ap-
proval by at least 75 % of the national bodies casting a vote.
International Standard ISOAEC 1864 was prepared by Joint Technical
Committee ISOAEC JTC 1, Information technology, Sub-Committee SC
11, Flexible magnetic media for digital data Werchange.
This fourth edition cancels and replaces the third edition
(ISO 1864:1985), of which it constitutes a technical revision.
Annexes A and B form an integral part of this International Standard.
Annex C is for information only.
0 ISO/IEC 1992
All rights reserved. No part of this publication may be reproduced or utilized in any form
or by any means, electronie or mechanical, including photocopying and microfilm, without
Permission in writing from the publisher.
lSO/IEC Copyright Office l Case Postale 56 l CH-1211 Geneve 20 l Switzerland
Printed in Switzerland
ii

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ISO/IEC 1864:1992(E)
INTERNATIONAL STANDARD
Information technology - Unrecorded 12,7 mm (0,5 in) wide
magnetic tape for information interchange - 32 ftpmm
(800 ftpi), NRZI, 126 ftpmm (3 200 ftpi) Phase encoded and
356 ftpmm (9 042 ftpi), NRZI
ISO 468:1982, Surface roughness - Parameters, their
1 Scope
values and general rules for specifying
requirements.
This International Standard specifies the character-
istics of 12,7 mm (0,5 in) wide magnetic tape with
ISO 1863:1990, Information processing - 94rack, 12,7
reel, to enable magnetic and mechanical inter-
mm (0,5 in) wide magnetic tape for information
changeability of such tape between information
interchange using MRZ 1 at 32 ftpmm (800 ftpi) - 32
processing Systems.
cpmm (800 cpi).
This International Standard applies solely to mag-
ISO/IEC 3788: 1990, Information processing - 9-track,
netic tape for digital recording using the NRZI
12,7 mm (0,5 in) wide magnetic tape for information
method of recording at 32 ftpmm and 356 ftpmm
interchange using Phase encoding at 126 ftpmm (3
(800 ftpi and 9 042 ftpi) or the Phase-encoded
200 ftpi}, 63 cpmm (1 600 cpi).
method of recording at 126 ftpmm (3 200 ftpi) in
which the direction of magnetization is nominally
ISO 5652: 1984, Information processing - 9-Track,
longitudinal.
12,7 mm (0.5 in) wide magnetic tape for information
NOTE 1 Some numeric values in the SI and/or Imperial interchange - Format and recording, using group
measurement System in this International Standard have
coding at 246 cpmm (6 250 cpi).
been rounded off and therefore are consistent with, but
not exactly equal to, each other. Either System may be
ISO 6098: 1984, Information processing - Self-loading
used, but the two should be neither intermixed nor re-
cartt-idges for 12,7 mm (0.5 in) wide magnetic tape.
converted. The original design was made using the Im-
perial measurement System.
ASTM D 2000, Rubber products in automotive appli-
cations, classification System for.
2 Normative references
3 Definitions
The following Standards contain provisions which,
For the purposes of this International Standard, the
through reference in this text, constitute provisions
following definitions apply.
of this International Standard. At the time of publi-
cation, the editions indicated were valid. All stan-
dards are subject to revision, and Parties to 3.3 magnetic tape: A tape that will accept and re-
agreements based on this International Standard tain the magnetic Signals intended for input, output
are encouraged to investigate the possibility of ap- and storage purposes on Computers and associated
plying the most recent editions of the Standards in- equipment.
dicated below. Members of IEC and ISO maintain
registers of currently valid International Standards.
3.2 Master Standard Reference Tape: A tape selec-
ted as the Standard for Signal amplitude.
ISO 209-1: 1989, Wrought aluminium and aluminium
alloys - Chemical composition and forms of prod-
NOTE 2 A Master Standard Reference Tape has been
established at the US National Institute of Standards and
ucts - Part 1: Chemical composition.
1

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ISO/IEC 1864:1992(E)
Technolgy (NIST) for the physical recording densities of
Traceability to the Standard Reference Amplitude is
32 ftpmm (800 ftpi) and 126 ftpmm (3 200 ftpi).
provided by the calibration factor(s) supplied with
each Secondary Standard Reference Tape.
A further Master Standard Reference Tape has been es-
tablished at the NIST for the physical recording density
3.10 reference edge: The edge furthest from an
of 356 ftpmm (9 042 ftpi).
observer when the tape is lying flat with the mag-
netic surface uppermost and the direction of move-
3.3 Secondary Standard Reference Tape: A tape for
ment for recording is from left to right.
which the magnetic characteristics are known and
stated in relation to that of the Master Standard
3.11 in-contact: An operating condition in which the
Reference Tape. it is intended that these be used for
magnetic surface of a tape is in contact with a mag-
calibrating tertiary reference tapes for use in routine
netic head.
calibration. See annex B.
3.12 track: A longitudinal area on a tape along
NOTE 3 Secondary Standard Reference Tapes are
which a series of magnetic Signals may be recorded.
available from the NIST, Office of Standards Reference
Materials, Room 205, Building 202, National Institute of
row: Nine transverse ly-related locations (one
Standards Technology, Gaithersburg, MD 20899, USA, 3.13
under the following part numbers:
ch tra ck) in which bits are recorded.
in ea
SRM 3200 for 32 ftpmm (800 ftpi) and 126 ftpmm
3.14 Position of flux transition: That Point which
(3 200 ftpi)
exhibits the maximum free-space flux density
normal to the tape surface.
SRM 6250 for 356 ftpmm (9 042 ftpi)
3.15 physical recording density: The number of re-
3,4 Average Signal Amplitude: The average peak-
corded flux transitions per unit length of track
to-peak value of the Signal output to the read head
(ftpmm or ftpi).
when measured over a minimum of 76 mm (3,0 in)
of tape.
3.16 data density: The number of data characters
stored per unit length of tape (cpmm or cpi).
3.5 Typical Field: In the plot of the Average Signal
3.17 resistance per Square: The surface resistance
Amplitude against the recording field at the speci-
of a Square area of any size measured between
fied physical recording density, it is the minimum
electrodes placed along two opposite sides of the
Geld that Causes an Average Signal Amplitude equal
Square. The unit of measurement is the ohm.
to 95 % of the maximum Average Signal Amplitude.
3.18 Oxide coating to brass and chrome: The re-
3.6 Reference Field: The typical field of the Master
sistance of the tape Oxide coating to motion on brass
Standard Reference Tape at the specified physical
(chrome).
recording density.
3.19 Oxide coating to tape back surface: The re-
3.7 Standard Reference Current: The current that
sistance of the tape Oxide coating to motion on the
produces the Reference Field.
tape back surface.
Traceability to the Standard Reference Current is
3.20 tape back surface to stainless steel: The re-
provided by the calibration factor(s) supplied with
sistance of the tape back surface to motion on
each Secondary Standard Reference Tape.
stainless steel.
3.8 Test Recording Current: The current that is k
3.21 rubber to tape back surface: The resi stance of
times the Standard Reference Current, where k
the ta pe back s urface to motion on rubber.
equals:
4 Environment
2,0 to 2,2 at 32 f?pmm (800 ftpi)
The conditions specified below refer to the ambient
1,75 to 1,85 at 126 ftpmm (3 200 ftpi)
conditions in the test or Computer room and not to
those within the tape drive equipment.
1,35 to 1,45 at 356 ftpmm (9 042 ftpi)
4.1 Testing environment
3.9 Standard Reference Amplitude; SRA: The Aver-
age Signal Amplitude from the Master Standard
Reference Tape when it is recorded with the appro- Unless otherwise stated, all measurements made
on a tape to check compliance with the require-
priate Test Recording Current at one of the specified
physical recording densities. ments of this International Standard and all tests
2

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ISO/IEC 1864:1992(E)
prescribed for a tape in this International Standard 5.4 Base material thlckness
shall be carried out under the environmental con-
ditions of 23 “C + 2 OC (73 “F + 4 OF) and relative The base material thickness shall be 0,038 mm
humidity 40 % t&60 %, after G least 24 h of con- (0,001 5 in) nominal.
ditioning in the Same environment.
5.5 Coatlng thickness
4.2 Operating environment
The coating thickness shall not exceed 0,015 mm
(0,000 6 in).
The operating temperature shall be within the range
16 “C to 32 “C (60 “F to 90 OF) and the relative hu-
midity 20 % to 80 %. Operation near the extremes 5.6 Length
of these ranges tan result in degraded Performance.
The wet bulb temperature shall not exceed 25 OC The normal minimum length of tape is 732 m
(78 OF). (2 400 ft) splice-free. If the length of the tape is less
than 732 m (2 400 ft), the actual length shall be
stated. Maximum tape length is limited by thickn’ess,
4.3 Storage environment
E value (see 5.7), moment of inertia and reel di-
mensions.
During storage, it is recommended that the tapes
are kept within the following conditions:
5.7 E value
4.3.1 Unrecorded tape
The E value is the radial distance by which the reel
flanges extend beyond the outermost layer of a tape
temperature: 5 “C to 48 “C (40 “F to 120 OF)
which has been wound at a tension of 2 N to 3,6 N
(7 ozf to 13 ozf) on the specified reel. The minimum
relative humidity: 20 % to 80 %
E value shall be 3,2 mm (0,125 in).
wet bulb temperature: not greater than 26 OC
When the tape is used with a self-loading cartridge
(80 OF)
(see ISO 6098), the E value shall satisfy:
6,3 mm (0,25 in) < E < 15,9 mm (0,625 in)
4.3.2 Recorded tape
temperature: 5 OC to 32 “C’(40 “F to 90 OF) 5.8 Elastoplastic properties
relative humidity: 20 % to 80 %
The elastoplastic properties of the tape shall be
such that when the tape is subjected to a tension of
wet bulb temperature: not greater than 26 “C
30 N (108 ozf) for a period of 3 min under any com-
(80 OF)
bination of temperature and relative humidity within
the ranges of IO “C to 50 “C (50 OF to 122 OF) and
20 % to 80 % relative humidity, the permanent
5 Characteristics of the tape
elongation measured with negligible tension after a
second 3 min interval is less than 1,0 %.
5.1 Material
5.9 Longitudinal curvature
The tape shall consist of a base material (oriented
There shall be a minimum radius of curvature for the
polyethylene terephthalate film or its equivalent)
edge of the tape, defined and tested by allowing a
coated on one side with a strong yet flexible layer
1 m (36 in) length of the tape to unroll and assume
of ferromagnetic material dispersed in a suitable
its natura1 curvature on a flat surface. The minimum
binder. If the tape is also coated on the rear surface,
radius shall be 33 m (108 ft). If measured over an arc
the coating shall be non-ferromagnetic.
of a circle, this corresponds to a deviation of
3,8 mm (1/8 in) from a 1 m (36 in) chord.
5.2 Width
5.10 Tape wind
Th e width of the tape shall be 12,7 Ti*: mm
I
500 -t~O,OOO l
9
(0 -0,004 In) *
Tape shall be wound, with its magnetic surface to-
ward the reel hub, in a clockwise direction; i.e. when
the reel is viewed from the front, the loose end of the
5.3 Total tape thickness
tape hangs from the right side of the reel. Tape shall
be wound with a tension of 2 N to 3,6 N (7 ozf to
The total tape thickness, at any Point, shall be
13 ozf) (see figure2).
0,048 mm + 0,008 mm (0,001 9 in + 0,000 3 in).

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iSO/iEC 1864:1992(E)
5.11 Magnetit properties 5.16 Test for missing Pulses and extra Pulses
The magne These tests shall be carried out in the in-contact
tic properties of the tape are not defi ned
condition and over the entire tested area, which
here by B- H loops or similar paramete rs, but are
shall extend from 0,2 m (8 in) before the BOT re-
defined by the testing procedu res given in 5.13 and
flective marker to 3,0 m (10 ft) beyond the EOT re-
5.15.
flective marker (see figure 1).
When performing the tests in 5.16.1 and 5.16.2, the
5.12 Test density
output or resultant Signal shall be measured on the
Same relative pass for both the Master Standard
For the purpose of testing tape in accordance with
Reference Tape and the tape under test, i.e. read-
this International Standard, the physical recording
while-write or read-on-first-pass-after-write. The
density shall be 32 ftpmm, 126 ftpmm or 356 ftpmm
SRA shall be measured at the appropriate density.
(800 ftpi, 3 200 ftpi or 9 042 ftpi). The flux transitions
shall be uniformly spaced. The flux transition spac-
516.1 Missing pulses
ing and the track configuration shall conform to
ISO 1863, ISO 3788 or ISO 5652 as appropriate.
When a tape has been recorded on all tracks as
specified in 5.12 and 5.13, and is played back on a
System, each channel of which has been calibrated
5.13 Typicai Fieid
as in 5.14, a missing pulse shall be either:
The Typical Field of the tape under test shall be
at 32 ftpmm (800 ftpi), any Signal from any track
a)
within + 20 % of the Reference Field for a physical
having a base-to-peak amplitude less than 50 %
-
recording density of 32 ftpmm (800 ftpi) or
of half the SRA;
126 ftpmm (3 200 ftpi) and within + 15 % of the Ref-
erence Field for a physical recording density of
at 126 ftpmm (3 200 ftpi), any pair of consecutive
W
356 ftpmm (9 042 ftpi).
output pulses from any track together having a
peak-to-peak amplitude less than 35 % of the
SRA;
5.14 Average Signal Ampiitude
at 356 ftpmm (9 042 ftpi), any Signal from any
C)
track having a base-to-peak amplitude less than
When read back on a System, each channel of which
35 % of half the SRA;
has been calibrated relative to the SRA, the Average
Signal Amplitude shall be within + IO % of the SRA
516.2 Extra pulses
at 32 ftpmm (800 ftpi), within TfF”h at 126 ftpmm
(3 200 ftpi) and within + _ 40 % at 356 ftpmm
(9 042 ftpi). Following DC-erasure of the tape on the machine
used for conducting the missing pulse test as de-
This test shall be conducted on the read-while-write
scribed in 5.16.1, any Signal from any track when
pass for both tapes.
measured base-to-peak which exceeds IO % of half
the SRA shall be an extra pulse.
NOTE 4 lt has been observed that the Average Signal
Amplitude level at 356 ftpmm (9 042 ftpi) tan vary along
5.16.3 Allowable number of missing pulses and
the length of tape. This effect is termed “tilt” and is the
of an investigation to determine its magnitude. extra pulses
subject
Results indicate that a Variation of 20 % tan be expected.
The effect of such variations is included in the specified
The allowable number of missing pulses and of ex-
tolerante on Average Signal Amplitudes.
tra pulses is not specified by this International
Standard, but is a matter for agreement between
interchange Parties.
5.15 Ease of erasure
NOTE 5 lt is considered impractical to specify this
number for the following reasons:
When a tape has been recorded according to any of
the conditions specified in 5.13 and then passed
a) the Performance of test equipment for magnetic tape
through a longitudinal unidirectional steady field of
is not uniform but depends on such things as tape
79 500 A/m (1 000 Oe), the remaining Average Sig-
tension, head design, and the method of guidance
nal Amplitude shall not exceed 4 % of the SRA for
employed;
that density.
b) different machines and Systems of programming vary
re fiel d shall be rea sona bly uniform, such
The erasu in their ability to tolerate missing and extra pulses on
the m iddle of a sole noid. tapes.
as that in
4

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ISO/IEC 1864:1992(E)
5.20 Resistance
5.17 Reflective markers
The electrical resistance of the magnetic surface
Esch reel sf tape shall be furnished with two photo-
shall be within the range of 5 x IO5 SZ to 5 x IO8 fl.
reflective markers, each consisting of, or equivalent
to, a transparent plastic base with a metallic (for
example, vaporized aluminium) coating sandwiched
5.21 Reflectivity
between the base and a thin layer of low cold flow
thermal setting adhesive.
5.24 .l Marker reflectivity
Reflective markers shall be placed on the side of the
The photo-reflective marker shall possess a
tape which does not carry the magnetic surface, and
reflectivity of at least 90 % compared to a reference
they shall be on opposite edges of the tape with the
Standard, at a 60° angle of incidence of light and
beginning-of-tape reflective marker (BOT) on the
over the range of wavelengths from 0,4 pm to
reference edge.
1,5 Pm (16 pin to 59 Pin).
The width of the markers shall be 4,8 mm + 0,5 mm
-
The reference Standard shall be constructed from a
(0,19 in + 0,02 in).
piece of aluminium Al-Mg 1 Si Cu (see ISO 209-1)
The length of the markers shall be 28 mm + 5 mm
- with a flat face dimension of 30 mm (1,2 in) by
(IJ in + 0,2 in).
5 mm (0,20 in) with a surface roughness R, (arith-
metical mean deviation) between 0,008 pm
The thickness of the markers, measured after their
(0,32 Pin) and 0,016 pm (0,63 yin) (see ISO 468). The
application to the tape, shall be not greater than
Standard should be resurfaced periodically to pre-
0,020 mm (0,000 8 in).
vent a reflectivity shift due to Oxidation.
The beginning-of-tape reflective marker (BOT) shall
5.21.2 Tape backing reflectivity
be placed 4,9 m + 0,6 m (16 ft + 2 ft) from the be-
ginning of the tapcand the end-of-tape marker (EOT)
The tape backing shall possess a reflectivity not ex-
shall be placed 7,6 ‘fi*o m (25 ‘Tz ft) from the end
ceeding 30 % of that of the reference Standard when
of the tape and such that the tested area is at least
measured under the conditions specified in 5.21.1.
720,6 m (2 363 ft) in length.
The distance from the outer edge of a marker to the
5.22 Dynamit frictional characteristics
adjacent edge of the tape shall be 0,8 mm max.
(0,031 in max.) and the marker shall not protrude
The forte specified in 5.22.1.1, 5.22.2.1, 5
...