1、INTERNATIONAL TELECOMMUNICATION UNION)45G134 - TELECOMMUNICATIONSTANDARDIZATION SECTOROF ITU-!).4%.!.#% ).4%2.!4)/.!,G0G04%,%0(/.%G0G0#)2#5)43-!).4%.!.#%G0G0/&G0G0!G0G0#)2#5)4&)44%$G0G07)4(G0G0!G0G0#/-0!.$/2)45G134G0G0RecommendationG0G0- (Extract from the “LUEG0“OOK)NOTES1 ITU-T Recommendation M.670
2、 was published in Fascicle IV.1 of the Blue Book. This file is an extract fromthe Blue Book. While the presentation and layout of the text might be slightly different from the Blue Book version, thecontents of the file are identical to the Blue Book version and copyright conditions remain unchanged
3、see below).2 In this Recommendation, the expression “Administration” is used for conciseness to indicate both atelecommunication administration and a recognized operating agency. ITU 1988, 1993All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means
4、 electronic ormechanical, including photocopying and microfilm, without permission in writing from the ITU.Fascicle IV.1 - Rec. M.670 1Recommendation M.670Fascicle IV.1 - Rec. M.670MAINTENANCE OF A CIRCUIT FITTED WITH A COMPANDOR1 In-station testsThe compandor should be tested at intervals determin
5、ed by the Administration. The tests should be inaccordance with the appropriate design information which should be made available in a suitable form to the repeaterstation staff.2 Circuit testsNo special objective test of the circuit to check the operation of the compandor is recommended, but when thecircuit is routine tested a speaking test should also be made.The unaffected level of the circuit and the noise advantage should be checked in accordance with 3 ofRecommendation M.590, at intervals determined by the Administration.
