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Hi. It seems that the g2 voltage of the picture tube is too high, resulting in a white screen, often with white horizontal lines. The g2 (= second grid) voltage is derived from the flyback high voltage. The voltage divider is mostly integrated in the flyback trafo housing.(including the adjustment knobs). A failure in this divider may lead to this defect. The static you hear may come from sparking in the divider. The flyback trafo is soldered onto the main printed cirrcuit board. Sometimes, one of the pins sits loose in the soldering pads. Turn on the set and observe for any sparking around the entire flyback circuitry, and, or the flyback trafo itself The screen turns black after a while, as a too high beamcurrent is detected. The set disables the flyback. Stand-by blinks meaning that there is a fault condition. Be carefull with the high voltages. The flyback voltage is very high (20-30 Kilovolts !) and may be lethal !!
You have to replace the flyback transformer of your monitor. Its a high voltage stepup tansformer which provides necessory volteges for the picture tube like Anode voltage, screen voltage and focus voltage. After some years of use the insulation stength of the flyback transformer will become bad and the high voltage will try to discharge trough the nearest ground poit. At that time you will hear the sprking sound. Its because of the high voltage Anode volt is discharing to the ground it will reflect on the screen. Using the monitor in this condition will result in the failure of horizontal driver transistor and even the power supply. Replacing the flybalck will solve your problem.
Hello, If everything else works - there is sound and high voltage (static on the screen) - but there is no picture (including no on-screen menus), this limits the likely area of problems is the video output circuitry or CRT filament connections. Check to see if the CRT filaments are glowing. If they are not glowing, check for bad soldering on the CRT neck board and around the flyback transformer.
Where the picture is erratic - coming and going entirely or changing brightness suddenly, with power off, remove the picture tube socket (carefully!) and clean the pins with fine sandpaper and use contact cleaner on the socket. This source of bad connections can result in a variety of erratic symptoms. Check for bad solder connections on the CRT neck board.
hello, If everything else works - there is sound and high voltage (static on the screen) - but there is no picture (including no on-screen menus), this limits the likely area of problems is the video output circuitry or CRT filament connections. Check to see if the CRT filaments are glowing. If they are not glowing, check for bad soldering on the CRT neck board and around the flyback transformer.
. This source of bad connections can result in a variety of erratic symptoms. Check for bad solder connections on the CRT neck board.
retrace lines usually means screen voltage is to high . that could mean bad picture tube.or flyback.
But there is something you could try. Be careful high voltage.on the back on the flyback transformer there to adjustments screen voltage and and focus go slightly counter clockwise or in your case clockwise that pot addustment will make it darker or lighter.If this does not fix it you have a flyback oy tue problem.
I hope this helps thanks doctor video leadingedgeelectronics 1987
help is here. back off that screen control tell them lines go away.
you have these things working Powersupply, Vertical, High voltage, sound, leaves video problem , go the the video circuit on schematic and find the video out transitor or ic or whatever they use, check to see if proper voltage or better yet see if got video with a scope, I see allot of shorted video out transistors.
also check and see if you can inject video with a vcr out to the tv in.
there is loose contact on the high voltage section in your tv.what you are going to do is open it,and reheat with soldering iron and a piece of soldering lead the video chroma section and the high voltage section,near the flyback