Home / Standards / GB/T 5443-1985 GB/T 5443-1985 Active The test methods for the technical specifications of ringing and tone for automatic telephone switchingnetwork 电话自动交换网铃流和信号音技术指标测试方法 Standard Type GBT ICS 33.040.30 CCS M15 Status 现行 Issue Date 1985-10-30 Implementation 1986-06-01 Responsible Dept 工业和信息化部（通信） Drafting Unit 工业和信息化部（通信）