若每条HW线均为PCM基群,则HW2TS5位于复用线上的TSX,其中X=() ["74","73","42","41"]
变压器中性点接地运行方式有何规定??
在PCM系统中,抽样频率() ["300hz","500hz","800hz","8000hz"]
忙时试呼次数缩写为()。 ["A、ISDN","B、BHCB","C、MTBF","D、BHCA"]
在采用比特型时间表调度时钟级程序时,设时间表共有16行、9列,则程序周期最多有()种。 ["A、16","B、9","C、3","D、5"]
热化系数及选择