Picture has lines on screen and is too bright

give a good whak on back of picture tube

I think you may have a tv tube problem...

Hello
You have stated that your TV has a lot of horizontal lines before it went off picture. We say that lines as retrace lines. So many of them will there on the entire screen, at about one inch or so apart, horizontaly scattered along with picuture. At that time, you may be unable to down the brightness control also. Even though you have reduced the brightness control to zero position, there will be some brightness level on the screen. You should have to repair that fault at the begining. There is a voltage going to the picture tube base, known as screen voltage. That voltage determine the emission of the picture tube, and we call it a bias voltage. When it goes higher than normal, this trouble ie retrace lines will occur. In long run it may spoil the picture tube itself. I don't know what the case of yours.
Anyway it is best for you to consult an experience technician in this case. Ok.

Hello
Adjust colour control to zero, and check for a pure black/white picture. Adjust contrast and brightness control to minimum and check whether the picture goes completly off or a slight picture prevails. If the picture goes out when you turn down brightness control to 1/3 position, that is about 20 points, your TVs screen voltage is very low, and it can be adjustable. If the picture does not go out and more brightness prevails, screen voltage is high. If the screen voltage is high, there will be some fine lines across the screen at about an inch apart; on the whole screen from top to bottom.
Screen voltage adjustment is critical for the clarity of the picture. If it is low, no proper colour will be dispayed. If it is high, it is harmful to both picture tube and your eyes.
Never try to adjust it without proper knowledge about it. The screen control can be located alongwith the LOT [Line Output Transformer], of your tv. There will have two adjustable controls there, one is for Focus, and the other is for Screen. Both are interactive, that is adjusting one will effect an other.

check the high voltage with the screen control turned up high where there is no raster. suspect problem within the video circuit where there is no high voltage or defective picture tube.some time when the screen is black and the screen control advanced,you can see if the tv has video or vertical or horizontal problems on the screen.service the high voltage circuit if there is no raster or high voltage is seen.no raster can be caused by the no heater or filament in the CRT.---- a defective picture tube can cause many problems, such as, poor brightness ,missing colors,intermittent picture,poor focus,a single-colored raster,arching in the gun assembly,retrace lines in the picture,negative picture,chassis shutdown,noheater or filament lit and no raster to name a few.an open filament or heater can cause no picture or no raster symptom.a defective CRT can have an extremely bright screen.loose particles of the cathode element can lodge between the grids and cause an intermittent black and white picture. simply tap the ends of the CRT gun assembly and notice if the picture begins to flash off and on.---- with a leaky picture tube after turn on the raster dims and get extremely bright.a dim picture with no green in the raster can result from a bad green assembly. a heater-to-cathode short can cause a raster to change colour or a result in no raster at all.replace the picture tube if there is severe arching in the neck of CRT. excessive brightness with retrace lines and a vertical collapse to a thin line can be caused by a bad coil on the neck board of the picture tube.rejuvenate the picture tube when there is very bright green screen. check for the resistance change on the resistors of the CRT neck board for an excessively bright picture with retrace lines.excessive dust inside the CRT spark gaps within the picture tube socket can cause the very bright raster and the chassis shutdown.a defective video amp,luminance buffer,or reference transistor can cause a bright picture with retrace lines. -------- for getting any required parts to replace you can get it from www.radioshack.com or from www.partstore.com or from www.shopjimmy.com --------- thanks.please do rate the solution.thank you for using fixya.keep updated.

vertical output ic needs to be resoldered. careful leaving that bright line displayed on the screen as this will cause a permanent phosphor burn into the tube. this can not be corrected once burned unless you replace the tube. mch

Hi Shailendrar , your problem sounds like vertical collapse , the whole picture has collapsed into a thin , very bright centre line ? maybe the result of dry solder joints , does banging on the side of the tv temporarily fix ? if so , the circuit board requires inspection for bad solder joints . Alternately the vertical chip/transistor may be blown , replace as required. Cheers T

If you feel good about opening your set then you can try this: Look for the flyback (high voltage) transformer, with the thick red wire which goes to the top of the picture tube. There are 2 controls on the flyback transformer, focus (top) and screen (bottom)Turn the brightness and contrast all the way down and then increase the screen control until you see retrace lines, and then back it down until those lines just vanish. Return the brightness and contrast to normal and adjust the focus control, if necessary, for a nice sharp picture. Let me know if that brings your brightness back.

This RCA set uses the CTC187BD chassis. Look on the back of the set and to the right of the cable connector you will see 2 controls sticking out, one on top of the other. The top control is for focus and the bottom one is screen, or overall brightness. If these controls have been turned clockwise then you will have a bright, fuzzy picture with white lines (retrace lines) through it. Tune in a channel with white letters on the screen and turn the top (focus) control until the letters are crisp and sharp. Go into the menu and turn the contrast and brightness all the way down, and then turn the bottom control (screen) until you can just see the picture, just above the point where the picture is too dark to see. Go back into the menu and reset the contrast and brightness and the picture will be back to perfect.

if the screen is real bright green with thin small white lines in it its probably a shorted picture tube. Or a shorted Green driver Transistor. Good Luck