BS8800时钟参考源丢失告警告警原因有()。 ["A、所配置的时钟参考源不存在","B、外部参考时钟故障","C、CC单板故障","D、线缆故障","E、载频故障"]
车轴轮座比原型公称尺寸的变化量为()。 ["+1-2mm","+2-3mm","+3-5mm","+3-6mm"]
以下哪项属于硬件故障()? ["坐标系误差","连接故障","海图误差","海图显示不当"]
6502型电气集中控制台调车信号复示器在调车信号开放时亮()。 ["红灯","绿灯","白灯","白闪"]
轴身及轴中央部直径比原型公称直径的减小量不大于()。 ["2mm","3mm","4mm","5mm"]
一个时隙可以提供多少码道?扩频因子决定一个时隙的码道数目吗?