Samsung 731BF no light

[retiredcaps]

Re: Samsung 731BF no light

hello
i have an lcd monitor,samsung 731bf that goes off from illuminocity almost imediately.

If I understand you correctly, it sounds like you are describing 2 seconds to black. If yes,

2 seconds to black can be

a) bad caps
b) bad ccfls
c) bad ccfl wiring (especially the return wiring)
d) bad secondary windings on the inverter transformer

More details starting with post #19 at

https://www.badcaps.net/forum/showthread.php?t=10419

Also, see budm's Inverter tester using old CFL

https://www.badcaps.net/forum/showthread.php?t=19987

here are some info

Post your pics and schematics following my instructions below exactly.

i placed it on the upper end of the last resistor on the left and to the ground.typically the output is 650 volt there.the cap didnt even warmed up even its rated 100V.

Indicate that in your picture. Right now, I have no idea what area you are talking about.

[xifias]

hello
i have an lcd monitor,samsung 731bf that goes off from illuminocity almost imediately.i changed the bulged caps from the power supply board,yet the problem insists.i found accidentally that if the voltmeter is in paralel on the high voltage output,it manages to stay on and show picture normally.
i tried a 47nF/100V capacitor that laid around instead of the voltmeter and it worked also.

but i want a more confident solution.why is that happening?will it be dangerous or so?its not mine you see,its for a friend,and i wont be able to monitor it after i give it back.

here are some info
http://monitory-lcd.magazyn.pl/pic_m...sung-731bf.jpg

http://www.gzskyhorse.com/images/FGH001.jpg

and the schematics

http://dc435.4shared.com/doc/NYMefbxe/preview001.png

http://dc435.4shared.com/doc/NYMefbxe/preview002.png


the model of the power supply board is IP-35155A

many thanks in advance!!

PS:the voltmeter is a typical multimeter,no high voltage.it reads no voltage,but the picture is on.i placed it on the upper end of the last resistor on the left and to the ground.typically the output is 650 volt there.the cap didnt even warmed up even its rated 100V.