彩电无光栅或光栅暗是一种常见故障。原因常与自动亮度控制、行扫描、显像管等电路异常有关。但在遥控彩电中还有一种使光栅变暗的原因,尚未引起人们的重视,本文就其现象和原因予以讨论。故障现象:一台金星C4918型彩电,即使将亮度、对比度调至最大,屏幕依然无光。将色饱合度调至最大,黑暗中才能见到一点影子。分析检修:根据经验,检查了自动亮度控制、 Colorless grating or raster dark is a common fault. Reasons often associated with automatic brightness control, line scan, CRT and other circuit anomalies. However, there is another reason for darkening the grating in the remote color TV, which has not attracted people’s attention. This article discusses the phenomenon and the reason. Symptoms: a Venus C4918-type TV, even if the brightness, contrast adjusted to maximum, the screen is still dull. To the full color saturation, the darkness to see a little shadow. Analysis and Maintenance: According to experience, check the automatic brightness control,