1、BRITISH STANDARD BS 6758:1987 Incorporating Amendments Nos 1, 2 and 3 IEC 558:1982 (including A1:1987 and A2:1993) Specification for Type C helical video tape recorders (Implementation of CENELECHD573S1)BS6758:1987 This British Standard, having been prepared under the directionof the Electronic Equi
2、pment Standards Committee,was published underthe authority of the BoardofBSI and comes intoeffecton 30April1987 BSI 11-1999 The following BSI references relate to the work on this standard: Committee reference EEL/22 Draft for comment 79/23889 DC and 86/27996 DC ISBN 0 580 15471 8 Committees respons
3、ible for this British Standard The preparation of this British Standard was entrusted by the Electronic Equipment Standards Committee (EEL/-) to Technical Committee EEL/22, upon which the following bodies were represented: Association of Sound and Communications Engineers Limited British Broadcastin
4、g Corporation British Kinematograph, Sound and Television Society Council for Educational Technology for the UnitedKingdom Electronic Engineering Association Independent Television Companies Association Industrial Council for Educational and Training Technology Ltd. Training and Educational Systems
5、Testing Bureau The following bodies were also represented in the drafting of the standard, through subcommittees and panels: Association of Professional Audio and Radio Consultants Association of Professional Recording Studios Limited Audio Engineering Society British Tape Industry Association Royal
6、 Photographic Society Amendments issued since publication Amd. No. Date of issue Comments 5722 November 1987 6404 September 1991 8906 September 1996 Indicated by a sideline in the marginBS6758:1987 BSI 11-1999 i Contents Page Committees responsible Inside front cover National foreword ii Foreword 2
7、1 Scope 3 2 Object 3 3 Format description 3 4 Environment 3 5 Tapes and spools 3 6 Transport geometry parameters and description of the basic system 4 7 Dimensions and location of records 5 8 Electrical parameters 8 Appendix A Transmission characteristics of the signal chain 19 National appendix Z T
8、ext deleted 20 Figure 1 Measurement of the curvature of the magnetic tape 10 Figure 2 Spools for television tape 11 Figure 3 Pole tip locations and drum dimensions 12 Figure 4 Record location and dimensions 13 Figure 5A Video and sync record locations for525-60 systems 14 Figure 5B Video and sync re
9、cord locations for625-50 systems 15 Figure 6A Tracking-control waveform and timing for525-60 systems 16 Figure 6B Tracking-control waveform and timing for625-50 systems (PAL) 17 Figure 6C Tracking-control waveform and timing for625-50 systems (SECAM) 18 Figure A.1 19 Figure A.2 19 Table I Spool dime
10、nsions 3 Table II Dimension B 3 Table III Approximate spool capacities 3 Table IV Record locations and dimensions 6 Table V 8 Table VI 8 Publications referred to Inside back coverBS6758:1987 ii BSI 11-1999 National Foreword This British Standard has been prepared by Technical Committee EPL/60, Recor
11、ding, and is identical with IEC558:1982 Type C helical video tape recorders as amended by Amendment No.1: February1987 and AmendmentNo2: September1993, published by the International Electrotechnical Commission (IEC). This British Standard is also in agreementwith Harmonization Document HD573 S1:198
12、2 and its amendmentA1: June1995, published by the European Committee for Electrotechnical Standardization (CENELEC). InFigure 5A the control track frame numbers associated with U, i.e. “87” and“288”, were corrected by Amendment No.1:1987 to read “77” and “278” respectively. A British Standard does n
13、ot purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Cross-references Publication referred to Corresponding British Sta
14、ndard BS EN 60094 (BS 6288) Magnetic tape sound recording and reproducing systems EN 60094-1:1993 (IEC 94-1:1981) Part 1:1994 Specification for general conditions and requirements EN 60094-2:1993 (IEC 94-2:1975) Part 2:1993 Specification for calibration tapes IEC 94-3:1979 BS 6288 Magnetic tape soun
15、d recording and reproducing systems Part 3:1990 Methods of measuring the characteristics of recording and reproducing equipment for sound on magnetic tape HD 311.6 S1:1987 (IEC 94-6:1985) Part 6:1987 Specification for reel-to-reel systems IEC 347:1982 BS 4967:1983 Specification for transverse track
16、video tape recorders IEC 503:1975 BS 5575:1978 Specification for spools for1 in (25.4 mm) video magnetic tape ISO 1860:1986 a BS 3732: Reels for magnetic tape for instrumentation applications Part 1:1988 Specification for precision reels with76mm (3in) centre hole a ISO 1860:1978 has been superseded
17、 by ISO 1860:1986. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, theHD title page, pages2 to20, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated i
18、n the amendment table on the inside front cover.HARMONIZATION DOCUMENT DOCUMENT DHARMONISATION HARMONISIERUNGSDOKUMENT HD573 S1/A1 June1995 UDC621.397.452 ICS33.160.40 Descriptors: Recording equipment, video recording, video tape recorder, magnetic tape, dimension, recording track, characteristic En
19、glish version Type C helical video tape recorders (IEC 558:1982/A2:1993) Magntoscopes enregistrement hlicodal de type C (CEI 558:1982/A2:1993) Videobandgerte mit Schrgspuraufzeichnung Typ C (IEC 558:1982/A2:1993) This amendment A1 modifies the Harmonization Document HD573 S1:1990; it was approved by
20、 CENELEC on1995-05-15. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for implementation of this amendment on a national level. Up-to-date lists and bibliographical references concerning such national implementation may be obtained on app
21、lication to the Central Secretariat or to any CENELEC member. This amendment exists in three official versions (English, French, German). CENELEC members are the national electrotechnical committees of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg,
22、Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and UnitedKingdom. CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels 1995
23、Copyright reserved to CENELEC members Ref. No. HD573 S1:1990/A1:1995 EBS6758:1987 2 BSI 11-1999 Foreword The text of amendment2:1993 to the International Standard IEC558:1982, prepared by SC60B, Video recording, of IEC TC60, Recording, was submitted to the formal vote and was approved by CENELEC as
24、amendment A1 to HD573 S1:1990 on1995-05-15 without any modification. The following dates were fixed: latest date by which the existence of the amendmenthas to be announced at national level (doa) 1996-01-01 latest date by which the amendment has to be implemented at national level by publication of
25、a harmonized national standard or by endorsement (dop) 1996-07-01 latest date by which the national standards conflicting with the amendment have to be withdrawn (dow) 1996-07-01BS6758:1987 BSI 11-1999 3 1 Scope This standard applies to magnetic video recording and/or reproduction using25.4mm (1 in)
26、 tape on type C helical video tape recorders suitable for broadcast applications. 2 Object The object of this standard is to define the electrical and mechanical characteristics of equipment which will provide for interchangeability of recordings. The requirements given are related to525 line-60 fie
27、ld and/or625 line-50 field systems. 3 Format description Two video recording heads are used, one for the active period of the field and a part of the vertical interval and one for the remainder of the vertical interval. Use of the latter head is optional. 4 Environment Tests and measurements made on
28、 the recorder to check the requirements of this standard shall be carried out under the following conditions: 5 Tapes and spools 5.1 Dimensions of magnetic tape for television The magnetic tape used for television recording shall conform to the following dimensions: 5.2 Spools 5.2.1 Spools shall con
29、form to the requirements ofISO Standard1860. The preferred spool diameters are listed in IEC Publication503: Spools for1 in (25.4mm) Video Magnetic Tape. If a friction ring is used, dimension C shall be: 115 mm (4.528in) The friction ring shall not impair spool performance or long-term storage of ta
30、pe. (SeeTable I and Table II andFigure 2, page 11.) Table I Spool dimensions Table II Dimension B Table III Approximate spool capacities 5.2.2 A minimum distance of3mm (0.12in) from the tape to the spool periphery shall be allowed. Approximate spool capacities are given inTable III. 5.3 Magnetic tap
31、e properties 5.3.1 The magnetic coating shall be longitudinally oriented. 5.3.2 The coercivity shall be more then30 10 3A/m. Temperature (drum diameter) 23 0.5 C Temperature (all other tests) 23 1 C Relative humidity 48% to 52% Barometric pressure 86 kPa to 106 kPa Conditioning before testing: 24 h
32、Millimetres Inches Width 25.350 0.9980 Maximum overall thickness 0.030 0.0012 Maximum longitudinal curvature 1.3 in 1 m 0.051 in 39.4 NOTEThe curvature shall be measured by standard IEC procedures as shown inFigure 1,page 10. +0.025 0.025 +0.001 0.001 +2 1 +0.079 0.039 Dimensions Millimetres Inches
33、Degrees A 76.2 3.000 C 114.0 4.500 0.010 D 82.5 3.250 0.002 E 5.60 0.219 G 120.0 0.1 H 0.65 max. 0.025 max. J 2.5 max. 0.098 max. K 91.5 min. 3.600 min. L 153 min. 6.000 min. M 30.8 0.1 1.212 0.003 Millimetres Inches 203.0 8.000 0.010 229.0 9.000 0.010 248.0 9.750 0.010 267.0 10.500 0.010 Diameter o
34、f spool Approximate capacity based upon nominal thickness of 0.030 mm Approximate maximum playing time (min) Millimetres Inches Metres Feet 625 line-50 field system 525 line-60 field system 203 8 650 2 100 45 44 229 9 900 3 000 62 61 248 9.75 1 125 3 700 78 77 267 10.5 1 400 4 600 97 95 +0.1 0.0 +0.
35、004 0.000 +0.5 0.0 +0.1 0.0 +0.15 0.00 +0.006 0.000 +0.5 0.0 +0.5 0.0 +0.5 0.0 +0.5 0.0BS6758:1987 4 BSI 11-1999 6 Transport geometry parameters and description of the basic system 6.1 Definitions of terms The following definitions of terms are given to assist in the correct understanding of this pa
36、rt of the standard. 6.1.1 Scanner The mechanical assembly comprising a drum, rotating pole tips and tape-guiding elements. It is used to record and reproduce video tape recordings. 6.1.2 Drum The circular cylinder around which tape is at least partially wrapped in order to form the head-to-tape inte
37、rface of a video tape recording system. 6.1.3 Upper drum That part of the drum in a helical-scan video recording system which does not contact the reference edge of the tape in this format. 6.1.4 Lower drum That part of the drum in a helical-scan video recording system which contacts the reference e
38、dge of the tape and usually contains tape-guiding elements. 6.1.5 Effective drum diameter The value of drum diameter which when used in theoretical calculations will correspond to the actual video record produced in a helical-scan video tape recording system. The effective value is equal to or great
39、er than the actual drum diameter. 6.1.6 Helix angle The angle formed between the path of the rotating pole tips and the tape-reference-edge guiding system on the scanner of a helical-scan video tape recording system. 6.1.7 Track angle The angle of the recorded video track with respect to the referen
40、ce edge of the tape in a helical video tape recording. 6.1.8 Centre span tension The calculated value of tape tension at a point midway between tape entrance and exit guides of the scanner in a video tape recording system. 6.2 Video and sync record system 6.2.1 Exactly one field of video shall be re
41、corded during each scanner revolution. The video record shall contain all active picture lines and sufficient vertical-sync information for playback synchronization. Information not contained in thevideo record is defined as the vertical-interval drop-out. 6.2.2 Recording of the missing vertical int
42、erval information shall be optional. However, no other information shall be recorded in the allotted tape area for525-60 systems. A longitudinal audio track (audio4) may be recorded in the area in lieu of the missing vertical information for625-50 systems. 6.2.3 The optional record of the vertical i
43、nterval information shall, contain a number of horizontal TV lines during the vertical interval, those of the vertical interval including drop-out and sufficient overlap of information for playback switching. 6.3 Scanner pole tips 6.3.1 There shall be six circumferential pole tip locations as shown
44、inFigure 3, page12 (top view). When an operational pole tip is not required, a suitable inoperative tip shall be placed in the same location. NOTEThe inoperative tips have mechanical characteristics similar to those of the pole tips but without any electrical function. Their main function is to caus
45、e the tape to assume the same deformation as that produced when a pole tip is used in the same place. 6.3.2 Each tip projection shall be0.06 0.03mm (0.0024 0.0012in) measured from the outer surface of the upper drum to the end of the pole tip. 6.3.3 The axial distance between each video-head pole ti
46、p and its associated sync-head pole tip shall be as shown inFigure 3 (side view). 6.4 Scanner guides 6.4.1 Location of the tape entrance and exit guides shall provide a tape-wrap angle such that the video record vertical-interval drop-out is10.00 0.25 horizontal lines for525-60 systems or11.90 0.30
47、lines in625-50 systems due to loss of head-to-tape contact, with no electronic switching of therecording signal. Start and end of the vertical-interval drop-out shall be measured at the half-amplitude points of the r.f. signal envelope produced by the video head. The measurements shall be made with
48、a tip projection of0.06mm (0.0024in). 6.4.2 The helix angle formed by the scanner and the associated tape guides shall be2 35 29 2 . 6.5 Drum diameter and tape tension Effective drum diameter, tape tension, helix angle,and tape speed completely determine the video-record track angle. Different metho
49、ds of design and/or minor variations in drum diameter and tape tension shall produce equivalent recordings for interchange purposes. Values and operating conditions specified in this sub-clause will produce the reference value of track angle. 6.5.1 The actual upper drum diameter shall be134.620mm (5.300 00in). +0.018 0.000 +0.000 71 0.000 00BS6758:1987 BSI 11-1999 5 The actual lower drum diameter shall be134.580mm (5.298 43in). 6.5.2 The upper drum shall rotate in synchron
