1、Union internationale des tlcommunications Place des Nations 1211 GENEVE 20 Suisse Switzerland Suiza COVERING NOTE GENERAL SECRETARIAT OF THE INTERNATIONAL TELECOMMUNICATION UNION Geneva, 20 July 2005 ITU TELECOMMUNICATION STANDARDIZATION SECTOR Subject: Erratum 1 (07/2005) to ITU-T Recommendation G.
2、703 (11/2001), Physical/electrical characteristics of hierarchical digital interfaces 1) In Figure 22/G.703 “Mask of a pulse corresponding to a binary 0 (at the 155 520 kbit/s interface)“, mask values were incorrect (pulse period of 19.3 ns instead of 6.43 ns). Replace the whole figure by the following: 2 2) In Figure 26/G.703 “Mask of a pulse corresponding to a binary 0 (at the 51 840 kbit/s interface)“, correct Note 4 as follows: NOTE 4 For the purpose of these masks, the rise time and decay time should be measured between 0.4 V and 0.4 V, and should not exceed 26 ns.