Shenzhen Xintian source Electronics Co., Ltd.
Address：Hongfa Industrial Park 1, 5th Floor, Shiyan Town, Baoan District, Shenzhen
Show blur is one of the common faults of various monitors display the main reasons blurred three aspects: First FBT (line output transformer) is focusing potential value of loose change or shift, causing the voltage applied to the CRT focus substandard, resulting in screen blurred; the second is the use of ambient humidity, causing the board to focus CRT tailstock pin rust, blurring occurs when CRT just power; Third debris within the CRT or CRT manufacturing processes internal cone bulb leaving focus (focuse) pole and the accelerating electrode (G2) between static dust, leaving the screen to form a very serious resistance blurred.
First, from the point of view of fuzzy extent, if blurring light, only the outline of the character becomes blurred, and the writing was still able to identify, are mostly the first reason;
If a large area of severely blurred, the screen goes white glow, and adjust the focus potentiometer on FBT also change screen brightness, are the third reason; if CRT just machines blurred with time, more and more clear this is typically the second reason.
For the first case, the fine-tuning of FBT Focus (focuse) potentiometer or simply replace the potentiometer to troubleshooting. For the second case, the general use of anhydrous alcohol to clean the discharge ring and tailstock to each electrode plugs and sockets, such as discharge ring rust serious tailstock parts can be replaced. For the third reason, remove the CRT transom, the CRT high voltage cap 24KV high voltage with a multimeter pen line lead to the CRT focus board socket, turn on the monitor, use a ground wire on the accelerating electrode G2 spark 2 to 3 times can be. Usually after 2 to 3 times a discharge will cause the focus (focuse) and the accelerating electrode (G2) dust extreme resistance between two electrodes breakdown. After restoring the original circuit, observe the clarity of the screen, then the appropriate adjustment to the focus potentiometer on FBT can make vague troubleshooting.
This method is commonly known as "playing Acking Law", which involve high voltage, you should be careful, and remember to protect the personal safety equipment, such as an accident, I am not responsible for IBM 2248 / G03, Envision / D350 display, with a rubber hammer head alignment gently hitting the middle part of the CRT screen several times, there may be fuzzy fault can be ruled out such a display.
Old point potentiometer located below the electron gun of the board, there are manual adjustment knob, stick the same. Now potentiometer should drive in the same, slightly larger than the drive where you want some.
Open the display cover is very dangerous, be careful, do not touch high-voltage ignition coil click ~~ will die ugly - really want to play on off 48 hours after opening the lid.