故障现象 分机通话结束之后,其开关从通话拨到守候位置,而主机始终处于摘机状态。分析检修 由于主机无法挂机时摘机功能正常,从而可判断开、关导频信号产生电路及主机的接收电路工作基本正常。此时应重点检查分机是否有延时发 Symptom After an extension call ends, its switch is dialed from the call to the waiting position, while the host is always in the off-hook state. Analysis and Maintenance As the host can not hang up hook function properly, which can determine the open and close pilot signal generation circuit and the host receiver circuit basically normal. At this point should focus on checking whether extension delay