First clockwise to adjust the screen grid voltage adjustment potentiometer , improving the screen grid voltage , then the screen , there are three possible situations: ( 1 ) there is still no light ; ( 2 ) was the level of a bright line grating ; ( 3 ) back to full screen raster scan lines . On " ( 1 ) " case, the components are easily damaged T702 line output transformer winding short , there are line output tube V702 (BU2508DF) breakdown , rarely is the line voltage protection tube V709 (2SC458) damage and flyback capacitor C715 (470pF/1600V), C726 (9100pF/1600V) and the line deflection coil shorted. On " ( 2 ) " case, usually field scanning block IC601 (TDA3653) damage , and some farm supply current limiting resistor R930 (2.2Ω) open, but also occasional feedback branch of R616 (15kΩ), R617 ( 8.2kΩ) and RP615 (4.7kΩ), RP618 (220Ω) or open resistance increases , but no scene power rectifier filter circuit is faulty. Of " ( 3 ) " a case, a pulse generation and transmission fort circuit failure . The components are easily damaged fortress slicer Zener diode V504 (H2-12A) breakdown or R705 (2.2Ω) open , there are R704 (2kΩ) resistance becomes larger or open .UTVservice manual download site

There are three cases of the above sound dull , just one adjustment ( screen grid voltage ) , two observation ( raster screen ) , you can quickly determine , troubleshooting.UTVservice manual download site