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广东惠州TCL通讯设备公司生产的HA868(Ⅲ)P/TSD型电话的设计性能是比较合理的、质量也较好,所以用户很欢迎。现以这种机型为例,介绍一下雷击损坏后的典型故障修理方法。电话机雷击后较普遍存在如下故障:不振铃无音、不能拨号、拨号音切不断,现逐步分析这几部分的工作原理和故障修理方法。一、不振铃在振铃电路中,A301、KA—2410及外围元件组成电子铃电路,VD305—VD308组成电子铃整流电路、V301为稳压二极管、C302为滤波电容、R302为电子铃灵敏度控制电阻、R304、C305控制着双音调振荡器的输出频率、R303、C303控制着双音调振荡器的切换频率、T301为输出变压器。
The design performance of HA868 (Ⅲ) P / TSD telephone produced by Guangdong Huizhou TCL Communication Equipment Company is more reasonable and the quality is better, so users are welcome. Now take this model as an example, introduce the typical failure repair method after the lightning damage. After telephone lightning strikes more commonly the following failures: no ringing no sound, can not dial, dial tone cut continuously, now the progressive analysis of these parts of the working principle and troubleshooting methods. A, no ring In the ringing circuit, A301, KA-2410 and the external components of the electronic bell circuit, VD305-VD308 form electronic bell rectifier circuit, V301 for Zener diode, C302 for the filter capacitor, R302 electronic bell sensitivity control Resistor, R304, C305 control the dual tone oscillator output frequency, R303, C303 control the switching frequency of dual tone oscillator, T301 for the output transformer.