akira 21SHS3 Series, Руководство по обслуживанию

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Model No: 21SHS3-CE.doc
Version 1.0
D Only vertical line in the middle of the screen
This is a dangerous failure. It probable causes flashover and smoking inside the set. Don’ t let your TV work for a long time as this failure appears. Because the electron beam can not move in the horizontal
orientation, the failure should be in the horizontal deflection circuit. We mainly check the open-circuit fault in horizontal deflection circuit. The detail checking and repairing steps are as follow:
E UOC does not work
In television, remote-control system is similar with the computer system. In theory , it can work if it holds two conditions as follow:
1) The power supply: In general, it is 5V, the error is not above 10% and the disturbance pulse is as small as possible.
2) The clock pulse: In TDA93XX circuit, the clock pulse is generated by pin58 / pin59 of N301 and 12M crystal oscillator.
Television’ s remote-control system also needs reset circuit that can preset the values in internal register. The circuit around pin57
of N204 is called auto-reset circuit. If UOC detects errors in resetting, it will come to the state of programme protected.
YES
YES
NO
Vertical line
Repair CRT The horizontal yoke is opened or not
Whether “ XS403” is opened
Check if there is bad solder between XS403, and the main board
Check L452, VD436, C467,C455,especial in inductive components and connector
NO