This electronic version (PDF) was scanned by the International Telecommunication Union (ITU) Library & Archives Service from an original paper document in the ITU Library & Archives collections. La présente version électronique (PDF) a été numérisée par le Service de la bibliothèque et des archives de l'Union internationale des télécommunications (UIT) à partir d'un document papier original des collections de ce service. Esta versión electrónica (PDF) ha sido escaneada por el Servicio de Biblioteca y Archivos de la Unión Internacional de Telecomunicaciones (UIT) a partir de un documento impreso original de las colecciones del Servicio de Biblioteca y Archivos de la UIT. (ITU) ﻟﻼﺗﺼﺎﻻﺕ ﺍﻟﺪﻭﻟﻲ ﺍﻻﺗﺤﺎﺩ ﻓﻲ ﻭﺍﻟﻤﺤﻔﻮﻇﺎﺕ ﺍﻟﻤﻜﺘﺒﺔ ﻗﺴﻢ ﺃﺟﺮﺍﻩ ﺍﻟﻀﻮﺋﻲ ﺑﺎﻟﻤﺴﺢ ﺗﺼﻮﻳﺮ ﻧﺘﺎﺝ (PDF) ﺍﻹﻟﻜﺘﺮﻭﻧﻴﺔ ﺍﻟﻨﺴﺨﺔ ﻫﺬﻩ .ﻭﺍﻟﻤﺤﻔﻮﻇﺎﺕ ﺍﻟﻤﻜﺘﺒﺔ ﻗﺴﻢ ﻓﻲ ﺍﻟﻤﺘﻮﻓﺮﺓ ﺍﻟﻮﺛﺎﺋﻖ ﺿﻤﻦ ﺃﺻﻠﻴﺔ ﻭﺭﻗﻴﺔ ﻭﺛﻴﻘﺔ ﻣﻦ ﻧﻘﻼ ً◌ 此电子版（PDF版本）由国际电信联盟（ITU）图书馆和档案室利用存于该处的纸质文件扫描提供。 Настоящий электронный вариант (PDF) был подготовлен в библиотечно-архивной службе Международного союза электросвязи путем сканирования исходного документа в бумажной форме из библиотечно-архивной службы МСЭ. © International Telecommunication Union INTERNATIONAL TELEPHONE CONSULTATIVE COMMITTEE (C.C.I.F.) XVIIth PLENARY ASSEMBLY Geneva, 4th to 12th October, 1954 ANNEXES TO VOLUME III LINE TRANSMISSION MEASUREMENTS ON LINES Published by the International Telecommunication Union Geneva, 1956 INTERNATIONAL TELEPHONE CONSULTATIVE COMMITTEE (C.C.I.F.) XVIIth PLENARY ASSEMBLY Geneva, 4th to 12th October, 1954 ANNEXES TO VOLUME III LINE TRANSMISSION MEASUREMENTS ON LINES I PAGE INTENTIONALLY LEFT BLANK PAGE LAISSEE EN BLANC INTENTIONNELLEMENT CONTENTS OF THE BOOK OF ANNEXES TO VOLUME III OF THE GREEN BOOK Part One — Annexes to the recommendations of the C.C.I.F. given in Volume 111 of the Green Book Page Annex 1. Calculation of the effects of echo and stability for a trunk/toll circuit .... 7 Annex 2. Cabling of racks for carrier systems as used by the Cuban Telephone Company 26 Annex 3. Note by the French Telephone Administration on cabling of standard “ 44 type ” apparatus rack s............................................................................................................... 26 Annex 4. Arrangement of cabling to reduce crosstalk on apparatus racks used for carrier systems by the British Telephone Administration.................................................. 27 Annex 5. Method used by the British Telephone Administration for balancing new un­ loaded symmetrical-pair cables designed to be used for 24-channel carrier tele­ phone system s ......................................... 28: Annex 6. Methods used in the Netherlands for balancing new unloaded symmetrical-pair cables designed to provide 48 carrier telephone c h a n n e ls..................................... 35 Annex 7. Method used by the French Telephone Administration for balancing repeater ° sections of cables containing unloaded symmetrical pairs designed to be used for 60-channel carrier s y s te m s ............................................. 37 Annex 8. Methods used in Mexico by the Sociedad Telefonos de Mexico for balancing unloaded symmetrical-pair cables designed to be used for carrier systems . 39 Annex 9. Specification for far-end crosstalk balancing networks used by the British Telephone Administration . 41 Annex JO. Specification for crosstalk balancing networks used in Mexico by the Socie­ dad Telefonos de M e x ic o .......................................................................................... 45 Annex 11. Method of synchronising frequencies used by the Bell System in U.S.A. on LI and L3 carrier systems on coaxial ca b les.................................................................. 48 Annex 12. Method used in France for checking master oscillators of a coaxial and sym­ metrical-pair cable network used for carrier sy s te m s............................................. 49' Annex 13. Synchronisation of carrier frequencies in the carrier cable network in the United Kingdom of Great Britain and Northern Ireland ................................................. 50' Annex 14. Main characteristics of stations emitting standard frequencies and time signals (information supplied by the C .C .I.R .)...................................................................... 52 Annex 15. Frequency standard used by the Italian Telephone Administration................. 54 Annex 16. Multi-purpose pilots used in the United States of America by the American Telephone and Telegraph Com pany............................................................................ 54 Annex 17. Multi-purpose pilots used by the French Telephone Administration................. 55 4 CONTENTS Page Annex 18. Multi-purpose pilots used by the British Telephone Administration.................. 55 Annex 19. Steps being taken or planned in different countries to improve transmission on old type trunk/toll c ir c u it s ....................................................................... 58 Annex 20. Dielectric strength tests ............................................................................... 66 Annex 21. Note by the French Administration on the definition of the cut-off frequency of a loaded c a b l e ........................................................................................................... 68 Annex 22. Study of telegraph distortion arising from phase distortion of the voice-frequency telegraph circuit (Note by the French Telephone A dm inistration)..................... 70 Annex 23. Note by the French Telephone Administration on the use of V.U. meters for the control of programme transm issions.................................................................. 74 Annex 24. Note by the Telephone Administration of the Federal German Republic on the use of peak programme meters for the control of programme transmissions . 76 Annex 25. Note by the British Telephone Administration on peak programme meters used in agreement with the British Broadcasting Corporation for monitoring pro­ gramme transm issions................................................................................................... 78 Annex 26. Note by the Telephone Administrations of France and Great Britain on methods of calculating transient response................................................................................... 80 Annex 27. Description of a volume regulator used on radio telephone circuits by the British Administration /. 86 Annex 28. Methods used in Switzerland for avoiding incorrect operation of singing sup­ pressors .............................................................................................................. 86 Part Two — Line measurement technique Section 1. — Steady-state A.C. measurements .......................................................................<). 89 1.1. Measurement of effective insertion loss and of insertion loss; tests of line trans­ formers 89 1.1.1. Measurement of effective insertion loss or effective insertion gain of any quadripole............................................................................................ 89 1.1.2. Measurement of insertion loss or gain of any quadripole................... 94 1.1.3. Tests of line transform ers........................................................................ 94 1.2. Measurement of transmission equivalent and of level over a frequency band . 97 1.2.1. Measurement of transmission equivalent of telephone circuits .... 97 1.2.2. Measurement of absolute or relative l e v e l s ....................................... 98 1.2.3. Apparatus for measurement of transmission equivalent and of level . 99 1.3. Measurement of repeater g a i n ........................................................................... 104 1.4. Measurement of impedance and of capacitance or inductance unbalance . 106 1.4.1. Steady-state impedance measurements.......................................... 106 1.4.2. Impedance measurements in the time d o m a in ................................... 110 1.4.3. Measurement of capacitance unbalances................................................ I ll 1.4.4. Measurement of inductance unbalances................................................ 112 1.5. Measurements of balance return loss, regularity return loss, return loss and active balance return l o s s .................................................................................... 113 1.5.1. Measurement of balance return lo s s ........................................................ 113 1.5.2. Measurement of regularity return lo s s .................................................... 115 CONTENTS 5 Page 1.5.3. Measurement of return l o s s .............................. ............................................ 116 1.5.4. Measurement of active balance return loss (echo attenuation) . .... 116 1.6. Measurement of transmission stability......................................................................... 116 1.6.1. Determination of singing p o in t....................................................................... 116 1.6.2. Measurement of the stability of a telephone cir c u it.................................... 119 1.6.3. Measurement of the singing margin (margin of stability) of a telephone circuit ................................................................................................................... 120 1.7. Measurement of phase distortion.................................................................................. 120 1.8. Measurement of non-linear distortion.........................................................................