1、 CENELEC ENxb3237-2 95 3404583 0363384 5T4 BRITISH STANDARD BS EN Methods of measurement Broadcast video tape recorders Part 2. Electrical measurements of analogue composite video signals The European Standard EN 61237-2 : 1995 has the status of a British Standard UDC 621.394.452 : 621.317.08 51237-
2、2 : 1995 EC 1237-2 : 1995 CENELEC EN*b1237-2 95 3404.583 0163185 430 BS EN 61237-2 : 1995 This British Standard, having been prepared under the direction of the Electrotechnical Sector Board, was published under the authority of the Standards Board and comes into effect on 15 December 1995 O BSI 199
3、5 Committees responsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee EPIJGO, Recording, upon which the following bodies were represented: Association of Professional Recording Services Limited Audio Engineering Society British Broadcasting
4、Corporation British Kinematograph, Sound and Television Society British !kpe Industry Association Federation of the Electronics Industry ITVAssociation (ITVA) National Council for Educational kchnology (NCET) Royal Photographic Society Royal %levision Society Amendments issued since publication I Te
5、xt affected The following BSI references relate to the work on this standard: Committee reference EPU6O Draft for comment 92/26134 DC ISBN O 580 24840 2 CENELEC EN*bL237-2 95 m 3404583 OLb3LBb 377 M BS EN 61237-2 : 1995 Contents page Committees responsible Inside front cover National foreword u Fore
6、word 2 kxt of EN 61237-2 3 i CENELEC EN*bL237-2 95 = 3404583 0163187 203 m BS EN 61237-2 : 1996 National foreword This British Standard has been prepared by Technical Committee EPU6O and is the English language version of EN 61237-2 : 1995 Broadcast Wo tape recorders. Methods of masu-t. Part 2 : Ele
7、ctrical measurements of analogue composite video signaEs, published by the European Committee for Electrotechnical Standardization (CENELEC). It is identical with IEC 1237-2 : 1995, published by the International Electrotechnical Commission (IEC). BS EN 61237 consists of the following parts: Part 1
8、Mechanical measurements Pari 2 Part 3 Part 4 Part 5 Part 6 Electrical measurements of analogue composite video signals Electrical measurements of analogue component video signals Measurements of audio performaneel) Electrical measurements of digital composite video signals and digital audio signals1
9、) Electrical measurements of digital component video signals and digital audio signals) Cross-references Publication referred to EN 60244-10 : 1993 (IEC 244-10 : 1986) EN 60756 : 1993 (IEC 756 : 1991) EN 61041-1 : 1995 (IEC 1041-1 : 1990) HD 527 S1: 1989 (IEC883: 1987) Corresponding British Standard
10、 BS EN 60244 Methods of measurement fw dio tmmitten Part 10 : 1993 Methods of measurement for television transmitten and transposers employing insertion test SiZ.dS BS EN 60756 : 1993 Non-broadcast video tape recorders. Time base stability BS EN 61041 Non-broadcast video tape recorders. Methods of m
11、asumt Part 1 : 1995 Geneml video (NTSC/IPAL) and audio BS 7595 : 1992 Measuring method fw chrominance signal-to-randmn noise ratio for video tape recorders (longitudinal) chamtics 1 in preparation. ii CENELEC EN*bL237-2 95 I 3404583 OLb3L8 /LIT m EUROPE“ STANDARD NORME EUROPENNE EUROPmm Nom EN 61237
12、-2 June 1995 UDC 621.394.452 : 621.317.08 Supersedes HD 439 S1 : 1983 Descriptors: Electroacoustics, video recording, recording apparatus, video tape recorders, radiocommunications, video signais, analogue signais English version Broadcast video tape recorders Methods of measurement Part 2: Eleetrie
13、al measurements of analogue composite video signals (IEC 1237-2 : 1995) Magntoscopes de radiodiffusion Mthodes de mesure Partie 2 : Mesures lectriques pour les signaux vido analogiques composites zusammengesetzten Videosignalen Videobandgerte fur den Rundfunk MeBverfahen Teil 2 : Elektrische Messung
14、en an Gerten fr analoge magnetische Aukeichnung von (CE1 1237-2 : 1995) (EC 1237-2 : 1995) Thic European Standard was approved by CENELEC on 19940348. CENELEC members are bound to comply with the CENKENELEC Internal Regulations which stipulate the conditions for giving this European Standard the sta
15、tus of a national standard without 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 CENELEC member. This European Standard exists in three official versions (English, French, German)
16、. A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Centrai Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Denmark, Fi
17、nland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CENELEC European Committee for Electrotechnical Standardization Comit Europen de Nonnalisation Electrotechnique Europisches Komitee fr Elektrotechnische
18、Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels O 1995 Copyright reserved to CENELEC members Ref. No. EN 61237-2 : 1995 E CENELEC EN*b3237-2 95 3404583 0363389 O86 Page 2 EN 61237-2 : 1995 Foreword The text of document 60B(C0)159 + 1594 future edition 1 of IEC 1237-2, prepared by SC
19、 60B, Video recording, of IEC TC 60, Recording, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61237-2 on 199443348. This European Standard supersedes HD 439 S1: 1983. The following dates were fixed - latest date by which the EN has to be implemented at national lev
20、el by publication of an identical national standard or by endorsement (dop) 1996-0501 latest date by which the national standards conflicting with the EN have to be withdrawn - (dow) 1996-0501 Annexes designated nonnative are part of the body of the standard. Annexes designated informative are given
21、 for information oniy. In this standard, annex ZA is nonnative and annexes A, B, C and D are informative. Annex ZA has been added by CENELEC. CENELEC EN*bL237-2 75 3404583 OLb3L70 BTB IPI Page 3 EN 61237-2 : 1995 CONTENTS Page FOREWORD Clause Scope and object Normative references . General Test cond
22、itions Measuring methods and test signals . 5.1 Manual and automatic measurements 5.2 Measurement of differences between adjacent tracks (fields/segments) 5.3 Procedure of measurement . 5.4 Test signals 5.4.1 Introduction . 5.4.2 Amplitudes and characteristics of test signals 5.4.3 Test signal arran
23、gement Measure men ts of characteristics 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 Amplitude of output signals in E- mode and playback . 6.1.1 Luminance bar amplitude error . 6.1.2 Synchronizing pulse amplitude error 6.1.3 Burst amplitude error . Short and line time distortions . 6.2.1 K factor . 6.2.2 2T
24、lbar ratio 6.2.3 Bar tilt . 6.2.4 Base-line distortion Chrominance-luminance gain inequality Chrominance-luminance delay inequality Amplitude/frequency characteristics . 6.5.1 Luminance . 6.5.2 Chrominance . Non-linear distortions . 6.6.1 Differential gain . 6.6.2 Differential gain versus frequency
25、6.6.3 Differential phase . 6.6.4 Group delay . Chrominance-luminance cross-talWintermodulation . Luminance signal-to-noise ratio Chrominance signal-to-noise ratio 6.9.1 Measurement of PAUNTSC colour video signals 6.9.2 Measurement of SECAM colour video signals . 2T 2 5 5 6 6 7 7 7 7 8 8 8 9 9 9 9 10
26、 10 10 11 12 13 14 15 16 16 16 17 17 17 18 18 19 20 21 21 22 a CENELEC EN*bL237-2 95 E 3404583 OLb3L9L 734 Page 4 EN 61237-2 : 1995 Clause Page 6.10 Field time distortions 23 6.10.1 Vertical tilt 23 6.1 1 Long time distortion 24 6.1 1.1 Signal bounce 24 6.1 1.2 Power supply interference . 24 7 Speci
27、al measurements . 7.1 FM characteristic frequencies . 7.2 Non-linear preemphasis . 7.3 Noise coring . 7.4 Moir . 7.5 Time base errors (measurements before time base error corrector) . 7.5.1 Velocity errors . 7.5.2 Phase step . 7.5.3 Jitter . 7.5.4 Time base errors after correction . 7.6 Sc/H phase 2
28、5 25 25 27 27 28 28 29 29 30 30 Annexes A (informative) Test signals elements . 34 B (informative) 625-line systems . 43 C (informative) 525-line systems . 52 D (informative) Bibliography 59 ZA (normative) Normative references to international publications with their corresponding European publicati
29、ons . 61 CENELEC ENxb2237-2 95 3404583 OLb3292 hi0 Page 5 EN 61237-2 : 1995 BROADCAST VIDEO TAPE RECORDERS - METHODS OF MEASUREMENT - Part 2: Electrical measurements of analogue composite video signals 1 Scope and object This part of IEC 1237 describes the test signals and measuring methods for equi
30、pments mainly dedicated to record/playback analogue composite TV-signals on magnetic tape on reels or in cassettes. The allowable tolerances for the rated values for acceptable performance are not given in this standard, but may be derived from the specifications for the related system, .e. appropri
31、ate publications, manufacturers specifications, etc. The necessary reference and calibration tapes are either mentioned in the specific IEC publication of equipment under test or included in IEC 1105 (reference tapes) and IEC 1295 (calibration tapes). The principal object of this standard is to desc
32、ribe the methods of measurement, test signals and procedures which may apply to characteristics of video recording/playback machines mainly intended for professional use. The measuring methods described here- after do not directly concern home equipment and it would appear that some will be difficul
33、t to apply to them. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this patt of IEC 1237. At the time of publication, the editions indicated were valid. All normative documents are subject to revision, and p
34、arties to agree- ments based on this part of IEC 1237 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. Members of IEC and IS0 maintain registers of currently valid International Standards. IEC 244-1 O: 1986, Methods of mea
35、surement for radio transmitters - Part 70: Methods of measurements for television transmitters and transposers employing insertion test signals IEC 756: 1991, Non-broadcast video tape recorders - Time base stability IEC 883: 1987, Measuring method for chrominance signal-to-random noise ratio for vid
36、eo tape recorders CENELEC EN*bL237-2 95 6 3404583 OLb3L93 507 Page 6 EN 61237-2 : 1995 IEC 1041 -1 : 1990, Non-broadcast video tape recorders - Methods of measurement - Part 7: General video (NTSUPAL) and audio (longitudinal) characteristics IEC 1041 -2: 1994, Non-broadcast video tape recorders - Me
37、thods of measurements - Part 2: Video characteristics chrominance CCIR Recommendation 471 -1: 1990, Nomenclature and description of colour bar signals (Vol. Xl-1) CCIR Recommendation 567-3: 1990, Transmission performance of television circuits designed for use in international connections (Vol. XII)
38、 3 General This standard deals with the application of measuring methods designed for general use television production and transmission as well as special measurement techniques for television tape machines. The methods are applicable to acceptance tests, performance comparisons and, as far as poss
39、ible, to routine checks. To insure that the results obtained at a specific time at a specific place are comparable to other measurements it is advisable to specify the test signals, measuring devices and types of tapes used together with the results obtained. Since measurements of television tape ma
40、chines on the basis of a single test-line per field may not be fully representative of the full-field performance (see 5.2 and 5.3), they may give results which differ from those obtained or calculated with full-field test signals. There- fore it is necessary to additionally specify the measuring me
41、thod .e. - single line measurement (line number); - block measurement (start-line, step-by-step line(s), number of steps); - full-field measurement. Additionally it should be stated if the selection of lines coincides with a single recordplayback head only. 4 Test conditions If not otherwise stated
42、all measurements shall be carried out at the following atmospheric conditions. Temperature (20 f 1) “C Relative humidity Air pressure Conditioning before testing 24 h (50 f 2) % 86 kPa to 106 kPa CENELEC EN*blt237-2 95 E3 3404583 0363374 443 81 Page 7 EN 61237-2 : 1996 5 Measuring methods and test s
43、ignals 5.1 Manual and automatic measurements If an automatic measuring device is designed to give reliable results under the special conditions of television tape recording/playback as e.g. drop-out, jitter, time-base errors, head switching or partly insufficient head-to-tape contact, a significant
44、improvement in measuring speed, accuracy and comparability of results can be achieved. Therefore preference was given to measuring methods which can be carried out by auto- matic measuring equipment or which are suitable for automatic measuring techniques. Except where a distinction is made in parti
45、cular clauses between manual and automatic methods of measurement, the measurement procedures given in this standard are valid for both methods. However, although in the case of automatic measurements the procedure is carried out automatically by the test signal analyzer, the various steps are descr
46、ibed as if they were performed manually. 5.2 Measurement of differences between adjacent tracks (fields/segments) All currently standardized recording formats make use of segmented recording techniques. The length of the segments (tracks) varies between approximately 16 lines and one field where the
47、 latter is often termed “non segmented recording“ which only indicates that there is no cut within the field. Since two or more heads are used for record and playback of the video information to and from the tracks it is desirable to restrict the measurement to segments related to a specific head. T
48、his requires a special signal arrangement which provides identical information to the heads or segments in turn. A suitable arrangement for most formats is to repeat a packet of up to 16 different signals of a duration of one line within a field and to make the signals identical in both fields. 5.3
49、Procedure of measurement The measurements shall be carried out by measuring the playback signal after recording on the same equipment (best-case configuration). In certain particular cases, if the multigeneration-performance of a video recording system is measured, the measurements shall be carried out by measuring the playback signal af- ter recording on a different machine (worst-case configuration). If the television tape machine under test is equipped with external controls, e.g. tracking control, gain control, etc. these controls shall be set to
