1、 STD-BSI BS EN ISO/IEC SbbL-ENGL LSS7 Lb24bb9 ObZbB88 57b BRITISH STANDARD Information technology - Data interchange on 12,7 mm wide magnetic tape caxtridges - 18 tracks, 1491 data bytes per millimetre u rn * The European Standard EN ISO/IEC 9661 : 1995 has the status of a British Standard ICs 35.22
2、0.20 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW _ - - _- - BS EN ISOAEC 9661 : 1997 STD*BSI BS EN ISO/IEC SbbL-ENGL 1997 Lb24bb9 ObZb889 402 direction of the DISC Board, was published under the authority of the Standards Board and comes ina effect on 15 July 1997 Amd. No.
3、 BS EN ISO/EC 9661 : 1997 Da Text affected National foreword This British Standard is the English language version of EN ISOLEC 9661 : 1995. It is identical with ISO/IEC 9661 : 1994. It supersedes BS 7062 : 1989 which is withdrawn. The UK participation in its prepamtion was entrusted to Technicai Co
4、mmittee IST/4, Magnetic and optid media for digital data, which has the responsibility to: - aid enquirem to understand the text; - present to the responsible internationaUEuropean committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed - monitor re
5、lated internationd and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement intemational or European pubiications referred to in this document may
6、 be found in the BSI Standards Catalogue under the section entitled Inteniational Stanch- id R to 5 x lo9 S for backcoated tapes. I l V V 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 electro
7、des except that through the coating under test Note - Particular attention should be given to keeping the surfaces clean. 6.14 Tape durability This International Standard does not specifi parameters for assessing tape durability. However, a recommended procedurr: is described in annex D. 6.15 Inhibi
8、tor tape This International Standard does not specify parameters for assessing whether or not a tape is an inhibitor tape. However, annex B gives further information on inhibitor tapes. 6 - - STD-BSI BS EN ISO/IEC SbbL-ENGL L777 Lb24bb7 ObZb904 547 W EN ISO/IEC 9661 : 1995 6.16 Tape abrasivity Tape
9、abrasivity is the tendency of the 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. 6.17 Pre-recording condition Prior to recording data or to testing, the tape shall have been erased using alternating magnetic
10、 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. 6.18
11、Magnetic recording characteristics The magnetic recording characteristics shall be as defined by the testing requirements given below. When performing these tests, the output or resultant signal shall be measured on the same relative pass for both a tape calibrated to the Master Standard Reference T
12、ape and the tape under test (read-while-write or first forward-rca-pass) on the same equipment. The following conditions shall apply to the testing of ail magnetic recording characteristics, unless otherwise stated: - tapecondition : pre-recording condition - tapespeed : not greater than 2.5 m/s - r
13、ead-wxk : within the Written track - azimuth alignment - write-gaplength : 1,4 pm f 0.2 pm - write head saturation density - tapctension : 2.2 N f 0,2 N - recording current : test recording current 6.18.1 Typical field The typicai field of the tape shall be between 90 % and 110 % of the reference fi
14、eld. Traceability to the reference field is provided by the calibration factors supplied with each Secondary Standard Reference Tape. : not greater than 6 between the mean write transitions and the read gap : 0,34 T .t 0,03 T 6.183 Signai amplitude The average signal amplitude at the physical record
15、ing density of 972 ftpmm shall be between 70 % and 140 96 of the standard reference amplitude. Traceability to the standard reference amplitude is provided by the calibration factors supplied with each Secondary Standard Reference Tape. 6.183 Resolution The ratio of the average signal amplitude at t
16、he physical recording density of 1 458 ftpmm to that at the physical recording density of 972 ftpmm shall be between 80 % and i20 96 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 s
17、upplied 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
18、 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
19、 Tape is provided by the calibration factors supplied with each Secondary Standard Reference Tape. 7 STD.BS1 BS EN ISO/IEC SbbL-ENGL 1797 lb24bb9 Ob2b705 485 EN ISO/IEC 9661 : 1995 Record a tone pattern which shall be the following sequence of flux transitions: O O O O O 1 O O O O O where: a = 1,029
20、 pm a2 = 0,514 p 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 fpmm signal) and the average signal amplitude of the 972 ftpmm signai. Both amplitude measure
21、ments should be made using suitable filters. 6.18.5 Narrow-Band Signai-to-Noise Ratio (NB-SNR) The narrow-band signal-to-noise ratio is the average signal amplitude mis power divided by the average integrated (side band) nns noise power, and is expressed in dB. 6.18.5.1 Requirement The NB-SNR ratio
22、shail be equal to, or greater than, 30 dB when normalized to a track width of 410 pm. The normalization factor is dB(410) = dB(W) + 10 log 410/W, where W is the track width used when measuring dB(W). 6.1852 Procedure The NB-SNR ratio shall be measured using a spectrum analyzer with a resolution band
23、width (RBW) of 1 kXz and a video bandwidth (VBW) of 10 Hz. The tape speed shall be 762 ds for the frequencies specified below. The NB-SNR ratio shall be measured as follows: i) ii) Measure the read-signal amplitude of the 972 ftpmm signal, taking a minimum of 150 samples over a minimum length of tap
24、e 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 MIz. For other tape speeds all the frequencies shall be linearly scaled. 6.19 Tapeq
25、uality 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 foliowing conditions shall apply to all quality testing requirements: environment tape condition tapcspeed read-track widt
26、h physical recording density write-gap length azimuth alignment write head saturation density recording current format tape tension : operating environment : pre-recording condition : 2ds : 410 pm : 972 fipmm : 1,4 pm I 0,2 prn : not greater than 6 between the mean write transitions and the read gap
27、 : 0,34 T f 0.03 T : test recording current : 18 tracks : 2,2 N f 0,2 N 8 EN ISOAEC 9661 : 1995 6.19.1 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 76, or less, of half the average signal amplitude for the
28、 preceding 25,4 mm of tape. 6.19.2 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 i mm of tape has been measured. The missing pulse zone rate shall be less than one in 8 x 106 flux transitions recorded. 6
29、.193 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-numbed tracks. A simultaneous missing pulse zone condition on two or more tracks of a 9-track group is a coincident missing pulse z
30、one. If a coincident missing pulse zone occurs at the same time in both groups of tracks, 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
31、pulse zone. No 165 m length of tape shall have more than 12 coincident missing pulse zones. No coincident missing pulse zone shall exceed 50 mm. Section 3 - Cartridge requirements - 7 Dimensional and mechanid characteristics of the cartridge - - - II m - a reel for the magnetic tape; The cartridge s
32、hall consist of the following elements: - a case; - - - a write-inhibit mechanism; - a leader block; - Dimensional characteristics are specified for those parameters deemed manutory for intercange and compatible use of the cartridge. Where there is freedom of design, only the functional characterist
33、ics of the elements described are indicated. In the figures a typicai 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
34、 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. = * * a magnetic tape wound on the hub of the reel; a locking mechanism for the reel; a latching mechanism for the leader block.
35、 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 is a general view of the whole cartridge; shows the front side of the case which lies on reference surface A, shows the top side of the case; shows the rear
36、 side of the case; shows the bottom side of the case which lies in reference surface C; shows the side of the case which lies in reference surface B; shows an enlarged view of a part of figure 4; shows an enlarged cross-section of a location notch; shows an enlarged cross-section of a detail of the
37、opening of the case; shows an enlarged partial cross-section of the cartridge in hand; shows the same cross-section as figure 12 but of the cartridge in the drive; shows schematically the teeth of the toothed rim; shows two views and an enlarged cross-section of the leader block; shows the fixation
38、of the tape to the leader block, and shows the leader block inserted in the case. 9 STD-BSI BS EN ISOIIEC SbbL-ENGL 1997 W Lb24bb9 13b26907 258 EN ISOAEC 9661 : 1995 7.1 The overall dimensions of the case shall be I, = 125.0 mm f 0,32 mm I, = 109.00 mm I 0.32 mm I,= 24,50mm Overail dimensions (figur
39、es 4 to 6) + 0.50 mm - 0,32 ii The comers of the case shall be rounded off as specified by r1 = 3,OO max. r2 = 4,O ma. r3 = 3,OO min. Write-inhibit mechanism (figures 4 and 5) 7.2 The write-inhibit mechanism shall have a flat surface identified by a visual mark, e.g. a white spot, when in the positi
40、on in which writing is inhibited. The flat surface shall be accessible through a window in the front of the case. The location and dimensions of the window are specified by I, = 11.80 mm I 0,25 mm I, = 15.60 mm i 0.25 mm I, = 7,40 mm f 0.25 mm 1, = 12,OO mm f 0,25 mm In the write-inhibit position th
41、e fiat surface of the write-inhibit mechanism shall be behind this window at a distance 1, = 2,55 mm min. from the front side of the case. In the write-enable position this surface shall be within 0.25 mm of the front side of the case. The force required for the operation of the write-inhibit mechan
42、ism shall be in the range 2N to 9N when applied tangentially to the surface of the case. This international Standard does not prescribe the actual implementation of the write-inhibit mechanism. For example, it can be a rotatable or a slidable element. The implementation may require a larger or addit
43、ional window but shall not impair the integrity of the case against potential contaminants. 73 Label area of the rear side (figures 5 and 6) On the rear side of the case there shall be a label area specified by l9 = 7,OO mm I 0,25 mm Zl0 = 80.00 mm I, , = 12.30 mm i 0,25 mm I, = 0.50 mm f 0,25 rnm r
44、, = 1,OO mm max. + 0.30 mm - 0.16 ii 10 v; * - STD*BSI BS EN ISOIIEC SbbL-ENGL 1997 Lb24bb9 Ob2b908 194 = EN ISO/IEC 9661 : 1995 7.4 On the top side of the case there shall be a label area, recessed by 0,50 mm I 0.25 mm, specified by l, i, 4, and in addition by Label area of the top side (figure 5)
45、I, = 3 1 ,00 mm i 0,25 mm il, = 75,00 mm Case opening (figures 4,5,7 and 9) + 0,u) mm - 0.16 ii 7.5 The case shall have an opening for the tape in which the leader block can be inserted (see also figure 17). This opening shall be specified by Il5 = 4,70 mm I 0,25 mm lI6 = 14.90 mm i 0,32 mm I, = 7.5
46、0 mm 0,25 mm 1, = 87,lO mm I 0,25 mm l, = 4,00 mm 0,25 mm r5 = 4.00 mm 0.25 mm Q =50“1 1“ Figure 7 shows at a larger scale the details of the configuration of the case opening as seen at the right-hand side of figure 2. i61 = 3,9 mm OS mm + OS mm = 16,9 mm - 0.4 im 16, = 3,O mm OS mm lu= 11,6mm10,5m
47、m O1 = l“130 y = 20“ f 2“ 7.6 There shall be two locating notches open towards the bottom side. These location notches shall be specified by Locating notches (figures 7,8 and 10) 1, = 106,Oo mm f 0.25 mm fZi = 5.00 mm t 0,25 mm lZ2 = 7.00 mm I 0,25 mm i, = 104,00 mm i: 0,25 mm I, = 230 rnrn i 0,25 m
48、rn = l“30130 y =2“130 7.7 Locating areas (figure 7) The bottom side of the case shall have three circular locating areas al, a2 and a3 which shall lie in the same horizontal plane within 0.25 mm. Areas u1 and u2 shall have a diameter of 10,00 mm I 0,25 mm. The position of their centres shall be spec
49、ified by 11 STD-BSI BS EN ISOIIEC SbbL-ENGL 1977 Lb24bh7 ObZbSOS O20 M EN ISOAEC 9661 : 1995 i, = 108.50 mm f 0.25 mm i, = 330 mm f 0,25 mm = 105.50 mm f 0,25 mm Area a3 shall have a diameter of 14,oO mm f 0,25 mm. The position of its centre shall be specified by i, = 31.25 mm f 0.25 mm i, = 54,50 mm I 0,25 mm Inside configuration of the case around the case opening (figures 7 and 11) 7.8 Figures 7 and 11 show the inside configuration of the case around the opening of the case. This configuration shall be defined as follows (see al
