1. At the beginning of the screen startup, the entire screen is reddish or blueish, and there will be a line displayed when it is turned on, but it will be restored after a while;
⒉. Occasionally the screen turns red during use, but it will be restored after a while;
3. The overall screen is white and red, with a heavy flyback line, and immediately turns off the screen, there is a black screen, there is no way to open it.
For this kind of failure, many people say that it is a hardware failure, some people say that the picture tube is scrapped, and some people say that it is caused by damage to the display driver. These views are wrong.
Causes of failure and countermeasures:
Of course, LCD display tube failures (such as electrode contact) will cause this failure phenomenon, but it is not impossible to repair it-a slight electric shock can be used, severe filament power windings may rewind, and sometimes this failure phenomenon may also be caused by Caused by welding failure, a certain color electron gun's visible discharge power supply resistance is open-circuit damaged or the resistance is too large. In addition, in some cases, there is only a certain degree of inter-electrode leakage, which usually does not require maintenance, but there will be an instantaneous color deviation when it is lit, and it will naturally recover after a few seconds.
For pole-touch (sometimes only leakage) faults, they can only be repaired by professional maintenance personnel, which is characterized by protective shutdown. For irregular color deviation faults, it can usually be solved by repairing the discharge power supply resistance and peripheral components of the relevant electron gun.
The fault phenomenon caused by the open circuit damage of the power supply resistance is the same as that of the contact pole. The full screen is brought back to sweep the line, a certain color is very bright, but it will not cause the protection to stop. The solution is very simple-replace the new resistor with the same resistance value! Of course, if the resistance becomes larger, it should also be updated. In the rainy season, we must take into account the oxidation of the CRT socket. Although there are few color deviation failures caused by this, the author has also encountered it. After analysis, it may be due to poor design or component quality.
I don't know if it is a design habit or other reasons. The color deviation has the greatest probability of failure, followed by blue, and finally green.
Please note that if the display has been used for more than five years, we can regard it as a color deviation failure caused by the aging of the electron gun of the LCD liquid crystal display.
