Symptom: After the start of the lack of green.kQQservice manual download site
Analysis and maintenance: the lack of a color display may have the following two reasons: (1) RGB three kinds of signal input missing a color signal, which may be the display card output signal is missing a color, that is, the graphics card itself; 2) from the RGB input to the tube between the three cathodes of the channel on a link failure. This channel includes a signal processing circuit, a video amplifier circuit, a protection and a development circuit. Use the oscilloscope to carefully check the lack of a color channel circuit, you can find the point of failure.kQQservice manual download site
With the oscilloscope's two red and black pen, respectively, access to the cathode of the CRT cathode GK test, GK no waveform, and BK, RK are waveform. And then use the oscilloscope test Q314 at the base A point. This point has a signal waveform, so judge the fault from Q314 base and GK between a component. First suspected Q314 damage. Welding Q314, static measurement is normal; taking into account the RV302 Department of carbon film potentiometer, prolonged heating may be deterioration or blown. Under the welding, with a multimeter test to find its twokQQservice manual download site
The end has been disconnected. After replacement, troubleshooting.kQQservice manual download site
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