Question about SAMTRON 55V 15" CRT Monitor

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Low brightness

I havelg cb775cna maonitor,its very low brightness. i cheked the voltages of filament and screen these are normal.i could't find any components abbout brightness section ..anybody help me?

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Re: low brightness

He is talking about the screw on the flyback. It is on the high voltage part of the circuity. I resell monitors and computers and I have to take off the back to get to this. I would not recommend it to a novice. This will light up your life. When you turn it up too much you get those scan lines across the screens. To find the fly back look for the heavy plastic thick thing on the circuit board to the back away from the picture tube. I had one of these on a samsung tv that looked like an arc welder. It is best to leave it unplugged for 48 hours for the electricity to discharge.

Posted on May 18, 2007

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Re: low brightness

I did not understand the term 'normal', but you can try increasing the screen from the FBT Potentiometer knob.

Posted on May 04, 2007

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Possible failure of the screen control potentiometer which is found near the line output transformer( fly back -LOT).
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Best take it to a shop or replace it..

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