1、CEN EN*:218b4 93 3404589 00b122L T51 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 21864 November 1993 CDC (i81.327.636 Supersedes EN 21864 : 1991 eccriptors: Data processing, information interchange, magnetic tapes, virgin medium, characteristics, dimensions, interchangeability, codification
2、 English version Information technology - Unrecorded 12,7 mm (O. 5 in) wide magnetic tape for information interchange - 32 ftpmm (800 ftpi), NRZ1, 126 ftpmm (3 200 ftpi) phase encoded and 356 ftpmm (9 042 ftpi), NRZ1 (ISO/IEC 1864 : 1992) Technologie de linformation - Bande magntique vierge de 12, 7
3、 mm (0.5 in) de large, pour lechange dinformation - 32 ftpmm (800 ftpi), NRZl, 126 ftpmm (3 200 ftpi) par codage de phase et 356 ftpmm (9 042 ftpi), NRZl (ISO/IEC 1864 : 1992) Informationstechnik - Unbeschriebenes 12,7 mm (0.5 in) breites Magnetband fr den Datenaustausch bei 32, 126 und 356 Flusswec
4、hsel/mm (800, 3 200 und 9 042 Flusswechel/in) (ISO/IEC 1864 : 1992) This European Standard was approved by CEN on 1993-11-25. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard w
5、ithout any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other languag
6、e made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, I
7、taly, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, 5-1060 Brussels O 1993 Copyright reserved to CEN members R
8、ef. No. EN 21864 : 1993 E CEN EN+21864 93 3404589 00bL222 998 Page 2 EN 21864 : 1993 Foreword On the proposal of the CEN Central Secretariat, the Technical Board decided to submit the International Standard, Information technology - Unrecorded 12,7 mm (O. 5 in) wick magnetic tape for infomation inte
9、rchange - 32 ftpwim (800 ftpi), NRZl, 126 ftpmm (3 200 ftpi) phase encoded and 356 ftpmm (9 042 ftpi), NRZl (ISO/IEC 1864 : 1992), to the formal vote. The result of the formal vote was positive. For the time being, this document exists only in English. This European Standard shall be given the statu
10、s of a national standard, either by publication of an identical text or by endorsement, at the latest by May 1994, and conflicting national standards shall be withdrawn at the latest by May 1994. In accordance with the CENKENELEC Internal Regulations, the following countries are bound to implement t
11、his European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN EN*2LBb4 33 m 3404589 O063223 824 m I N TE R NAT I O NA L STANDARD ISOAEC Fourth edition 1992-06-
12、1 5 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 linformation - Bande magntique vierge de 12,7 mm (0,5 in) de large, pour /change d
13、information - 32 ftpmm (800 flpi), NRZI, 126 flpmm (3 200 flpi) par codage de phase et 356 flpmm (9 042 flpi), NRZI Reference number ISOIIEC 1864:1992(E) I CEN ENlr23864 93 3404589 O063224 760 m Foreword IS0 (the International Organization for Standardization) and IEC (the In- ternational Electrotec
14、hnical Commission) form the specialized system for worldwide standardization. National bodies that are members of IS0 or IEC participate in the development of International Standards through technical committees established by the respective organization to deal with particular fields of technical a
15、ctivity. IS0 and IEC technical com- mittees collaborate in fields of mutual interest. Other international or- ganizations, governmental and non-governmental, in liaison with IS0 and IEC, also take part in the work. In the field of information technology, IS0 and IEC have established a joint technica
16、l 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 ISO/IEC 1864 w
17、as prepared by Joint Technical Committee ISOAEC JTC 1, Information technology, Sub-Committee SC 11, Flexible magnetic media for digital data interchange. This fourth edition cancels and replaces the third edition (IS0 1864:1985), of which it constitutes a technical revision. Annexes A and B form an
18、integral part of this International Standard. Annex C is for information only. O ISO/iEC 1992 All rights reserved. No part SRA: The Aver- age Signal Amplitude from the Master Standard Reference Tape when it is recorded with the appro- priate Test Recording Current at one of the specified physical re
19、cordi ng densities. Traceability to the Standard Reference Amplitude is provided by the calibration factor(s) supplied with each Secondary Standard Reference Tape. 3.10 reference edge: The edge furthest from an observer when the tape is lying fiat with the mag- netic surface uppermost and the direct
20、ion of move- ment for recording is from left to right. 3.11 in-contact: An operating condition in which the magnetic surface of a tape is in contact with a mag- netic head. 3.12 track: A longitudinal area on a tape along which a series of magnetic signals may be recorded. 3.13 row: Nine transversely
21、-related locations (one in each track) in which bits are recorded. 3.14 posltion of flux transition: That point which exhibits the maximum free-space flux density normal to the tape surface. 3.15 physical recordlng density: The number of re- corded flux transitions per unit length of track (ftpmm or
22、 ftpi). 3.16 data density: The number of data characters stored per unit length of tape (cpmm or cpi). 3.17 resistance per square: The surface resistance of a square area of any size measured between electrodes placed along two opposite sides of the square. The unit of measurement is the ohm. 3.18 o
23、xide coating to brass and chrome: The re- sistance of the tape oxide coating to motion on brass (chrome) . 3.19 oxide coating to tape back surface: The re- sistance of the tape oxide coating to motion on the tape back surface. 3.20 tape back surface to stainless steel: The re- sistance of the tape b
24、ack surface to motion on stainless steel. 3.21 the tape back surface to motion on rubber. rubber to tape back surface: The resistance of 4 Environment The conditions specified below refer to the ambient conditions in the test or computer room and not to those within the tape drive equipment. 4.1 Tes
25、ting environment Unless otherwise stated, ali measurements made on a tape to check compliance with the require- ments of this International Standard and all tests 2 CEN EN*ZL864 93 W 3404589 0061227 47T prescribed for a tape in this International Standard shall be carried out under the environmental
26、 con- ditions of 23 “C * 2 “C (73 OF * 4 OF) and relative humidity 40 Oh to 60 YO, after at least 24 h of con- ditioning in the same environment. 4.2 Operating environment The operating temperature shall be within the range 16 OC to 32 “C (60 OF to 90 OF) and the relative hu- midity 20 ?lo to 80 %.
27、Operation near the extremes of these ranges can result in degraded performance. The wet bulb temperature slicill not exceed 25 OC (78 “F). 4.3 Storage environment During storage, it is recommended that the tapes are kept within the following conditions: 4.3.1 Unrecorded tape temperature: 5 “C to 48
28、“C (40 “F to 120 OF) relative humidity: 20 10 to 80 Yo wet bulb temperature: not greater than 26 “C (80 OF) 4.3.2 Recorded tape temperature: 5 “C to 32 “C (40 OF to 90 OF) relative humidity: 20 YO to 80 O% wet bulb temperature: not greater than 26 “C (80 OF) 5 Characteristics of the tape ISOIIEC 186
29、4:1992(E) 5.4 Base material thickness The base material thickness shall be 0,038 mm (0,001 5 in) nominal. 5.5 Coatlng thickness The coating thickness shall not exceed 0,015 mrn (0,000 6 in). 5.6 Length The normal minimum length of tape is 732 m (2 400 fi) splice-free. If the length of the tape is le
30、ss than 732 m (2 400 fi), the actual length shall be stated. Maximum tape length is limited by thickness, E value (see 5.7), moment of inertia and reel di- mensions. 5.7 Evalue The E value is the radial distance by which the reel flanges extend beyond the outermost layer of a tape which has been wou
31、nd at a tension of 2 N to 3,6 N (7 ozf to 13 ozf) on the specified reel. The minimum E value shall be 3,2 mm (0,125 in). When the tape is used with a self-loading cartridge (see IS0 6098), the E value shall satisfy: 6,3 mm (0,25 in) E Q 15,9 rnrn (0,625 in) 5.8 Elastoplastic properties The elastopla
32、stic properties of the tape shall be such that when the tape is subjected to a tension of 30 N (108 020 for a period of 3 min under any com- bination of temperature and relative humidity within the ranges of 10 “C to 50 “C (50 “F to 122 OF) and 20 Yo to 80 % relative humidity, the permanent elongati
33、on 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 polyethylene terephthalate film or its equivalent) coated on one side with a strong yet flexible layer of ferromagnetic ma
34、terial dispersed in a suitable binder. If the tape is also coated on the rear surface, the coating shall be non-ferromagnetic. 5.2 Width The width of the tape shall be 12,7 1:; mm (0,500 4,004 in). t0,000 5.3 Total tape thickness The total tape thickness, at any point, shall be 0,048 mm k 0,008 rnm
35、(0,001 9 in k 0,000 3 in). There shall be a minimum radius of curvature for the edge of the tape, defined and tested by allowing a 1 m (36 in) length of the tape to unroll and assume its natural curvature on a flat surface. The minimum radius shall be 33 m (108 fi). If measured over an arc of a circ
36、le, this corresponds to a deviation of 3,8 mm (1/8 in) from a 1 m (36 in) chord. 5.10 Tape wind Tape shall be wound, with its magnetic surface to- ward the reel hub, in a clockwise direction; .e. when the reel is viewed from the front, the loose end of the tape hangs from the right side of the reel.
37、 Tape shall be wound with a tension of 2 N to 3,6 N (7 ozf to 13 ozf) (see figure 2). 3 - CEN ENxilLBb4 93 m ISOIIEC 1864:1992(E) 5.11 Magnetic properties The magnetic properties of the tape are not defined here by B-H loops or similar parameters, but are defined by the testing procedures given in 5
38、.13 and 5.15. 5.12 Test density For the purpose of testing tape in accordance with this International Standard, the physical recording density shall be 32 ftpmm, 126 ftpmm or 356 ftpmm (800 Rpi, 3 200 ftpi or 9 042 ftpi). The fiux transitions shall be uniformly spaced. The flux transition spac- ing
39、and the track configuration shall conform to IS0 1863, IS0 3788 or IS0 5652 as appropriate. 5.13 Typical Field The Typical Field of the tape under test shall be within f 20 Yo of the Reference Field for a physical recording density of 32 ftpmm (800 ftpi) or 126 Rpmm (3 200 ftpi) and within f 15 YO o
40、f the Ref- erence Field for a physical recording density of 356 Rpmm (9 042 ftpi). 5.14 Average Signai Amplitude When read back on a system, each channel of which has been calibrated relative to the SRA, the Average Signal Amplitude shall be within b) at 126 ftpmm (3 200 fipi), any pair of consecuti
41、ve output pulses from any track together having a peak-to-peak amplitude less than 35 Yo of the SRA; c) at 356 Rpmm (9 042 Rpi), any signal from any track having a base-to-peak amplitude less than 35 Oh of half the SRA; 5.16.2 Extra pulses Following OC-erasure of the tape on the machine used for con
42、ducting the missing pulse test as de- scribed in 5.16.1, any signal from any track when measured base-to-peak which exceeds 10 YO of half the SRA shall be an extra pulse. 5.16.3 Allowable number of missing puises and extra pulses The allowable number of missing pulses and of ex- tra pulses is not sp
43、ecified by this International Standard, but is a matter for agreement between interchange parties. NOTE 5 It is considered impractical to specify this number for the following reasons: a) the performance of test equipment for magnetic tape is not uniform but depends on such things as tape tension, h
44、ead design, and the method of guidance employed: b) different machines and systems of programming vary in their ability to tolerate missing and extra pulses on tapes. 4 CEN EN*2LBb4 93 5.17 Reflective markers Each reel of tape shall be furnished with two photo- reflective markers, each consisting of
45、, or equivalent to, a transparent plastic base with a metallic (for example, vaporized aluminium) coating sandwiched between the base and a thin layer of low cold flow thermal setting adhesive. Reflective markers shall be placed on the side of the tape which does not carry the magnetic surface, and
46、they shall be on opposite edges of the tape with the beginning-of-tape reflective marker (BOT) on the reference edge. The width of the markers shall be 4,8 mm I0,5 mm (0,19 in k 0,02 in). The length of the markers shall be 28 mm k 5 mm (1,l in k 0,2 in). The thickness of the markers, measured after
47、their application to the tape, shall be not greater than 0.020 mm (0.000 8 in). The beginning-of-tape reflective marker (BOT) shall be placed 4,9 m k 0,6 m (16 ft k 2 ft) from the be- ginning of the tape and the end-of-tape marker (EOT) shall be placed 7,6 ?$ m (25 -7i ft) from the end of the tape a
48、nd such that the tested area is at least 720,6 m (2 363 ft) in length. The distance from the outer edge of a marker to the adjacent edge of the tape shall be 0,8 mm max. (0,031 in max.) and the marker shall not protrude beyond the edge of the tape. The markers shall be free of wrinkles and excessive
49、 ad hesive. NOTE 6 It is desirable that the thinnest markers be employed which perform satisfactorily in minimizing the distortion of the layers of tape adjacent to them. 5.18 Cupping Cupping is the departure across the width of tape from a flat surface. The maximum cupping of a 6,35 mm (0,25 in) long length of tape shall not ex- ceed 0,25 mm (0,010 in) when placed concave side down on a smooth, flat surface. The time between cutting and the measurement should be 1 h. 5.19 Opacity Opacity is a characteristic which limits the amount of transmission of light through the t
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