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目前,TDA(飞利浦)国产二片彩色电视机,深受用户欢迎。本文以飞跃47C3-3型彩电为例,简要介绍它的维修。故障现象1 开机后,屏幕既无光栅出现,也无伴音。用万用表测不到整机所需的115V、26V、16V、12V 电压。分析检修:无光栅无伴音一般都是电源部分的故障。本机电源采用改进型的东芝分立开关电源,由开关管(BUT_(11))、桥式整流器、频率脉宽调制器、误差放大器、开关变压器等组成。无光栅无电压输出的原因,大多是开关稳压电路没有起振:(1)整流管6703～6706中有一个击穿,整流管击穿后,一般都要烧毁2A 熔丝。
At present, TDA (Philips) made two color TV sets, welcomed by users. This leap 47C3-3 color TV, for example, a brief description of its maintenance. Symptom 1 boot, the screen neither raster nor audio. Can not measure with a multimeter required 115V, 26V, 16V, 12V voltage. Analysis and maintenance: no grating no sound is generally part of the power failure. This machine adopts improved Toshiba discrete switching power supply, the switch (BUT_ (11)), bridge rectifier, frequency pulse width modulator, error amplifier, switching transformers and other components. No grating no voltage output, most of the switching regulator circuit is not starting: (1) rectifier 6703 ~ 6706 in a breakdown, the rectifier breakdown, the general must burn 2A fuse.