1、INTERNATIONAL TELECOMMUNICATION UNION)45G134 2 TELECOMMUNICATIONSTANDARDIZATION SECTOROF ITU4%,%2!0(94%,%2!0(G0G042!.3-)33)/.0%2)/$)#)49G0G0/ amended at New Delhi, 1960and Geneva, 1964)The CCITT,consideringthat, for technical supervision of operations, maintenance measurements on international voice
2、-frequencytelegraph (VFT) channels are necessary,unanimously declares the view(1) that maintenance measurements be carried out on international VFT channels once every three months(once every six months for 50-baud channels spaced at 240 Hz conforming to Recommendation R.35 bis);(2) that there is no need to carry out measurements more frequently on channels making up long circuits orcircuits used in a switched network;(3) that, when it is observed that the number of maladjustments is too high, supplementary measurementsshould be performed by agreement between the Administrations concerned.
