I was constantly correcting the focus and eventually, the blue went into a pincushion effect and I'm not shure what teh problem is. It is too out of alignment for the convergence to fix. Does anybody have a solution to this problem? Any info would help.
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there seems to be a problem in the horizontal circuit...there is a control on the flyback transformer that is labeled "screen". (you'll have to take the back off) The flyback is the component that looks sort of round with the red high voltage lead coming out the top and connecting to the top of the picture tube.On the back of the flyback there will be 2 or 3 controls if 2 there will be 1 focus and 1 screen, if 3 there are 2 focus and 1 screen..using an insulated flat blade screwdriver, slowly turn the screen control counterclockwise to see if this will make the lines go away...if not then there is a horizontal cicuit fault and quit possibly a pincushion problem(hourglass effect)..these will need to be checked by a service shop
The pincushion it intimately related to the horizontal circuits,the electron beam must travel farther to reach the corners of the crt and it does to the middle and so without pincushion circuits the raster would be bowed in on the sides on crts 27 inches are larger.Pincushion corrections straightens the raster by modulating the horizontal yoke current at a vertical rate.In an RCA tv the pincushion circuits are usually numbered 4800and the pin amp will probably be numbered 4801,its drive transistor should be Q4802,R4802 will be the width control,and R4805 the e/w pin amplitude. its inputs from the vertical should be Q4801 (subtractor) Q4803 (buffer) you should have a parabola waveform at 4801,yoke current can be modulated here without effecting high voltage.when Q4802 conducts voltage should decrease across Q4801 and the voltage drop across the yoke increases. The east west pin amp control 4805 controls how much of the vertical parabola is input to U4801 to compensate for changes in width caused by variations in beam current.By varying the e/w control resistor you can know if the circuit fault is in the input or output,if the picture varies in size the fault is in the input to U4801,if it does not vary check the output or U4801......hope that helps
Most projection TVs have an option to refocus. For example, my Sony rear projection TV has a button on the front for focusing the lamps. Try finding this button or option in the menus with your remote.
Projection TVs actually use three lamps, one red, one green and one blue. These need to line up exactly in order to form a good picture, and when they come out of focus, you see the edges which sometimes has the effect of a 3D image when you aren't wearing 3D glasses.
Hope this helps!
The set has 3 IC's(one for each color)strictly dedicated for the aligment of each color,if one them does not align is because is going bad or is already bad becuase picture can not be adjusted,the IC's can be identify because they are mounted on a heat sink and have the markings STK--- ---,they are all the same and need to be replaced with an exact replacement.If you are familiar with tv service you can replace them,sometimes the new ones need to be aligned from the service menu,you will need the service manual,soldering and unsoldering will be involved,If you are not too familiar be safe and seek the assistance of a servicer.