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前面介绍了HCD9919P/TSDL LCD电话机的工作原理,为了快速地维修电话机,下面列举其可能出现的有关故障现象,并介绍了这些故障现象的检修方法。 1.普通铃声 (1)不振铃。故障原因:a.整流电路存在故障。在振铃状态时,整流桥输人端铃流电压,若电压为0V,
The principle of operation of the HCD9919P / TSDL LCD telephone is described above. In order to quickly repair the telephone, the following is a list of the possible symptoms that may occur. The maintenance methods for these malfunctions are also described below. 1. Normal Ringtones (1) Not ringing. Fault causes: a rectifier circuit fault. In the ringing state, the rectifier bridge input terminal ringing voltage, if the voltage is 0V,