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Re: Television has no picture
That TV uses the PTK195 chassis, and the fact that you see only a thin line for each color near the bottom of the screen tells me your vertical output IC has stopped working, and is putting a small DC voltage across the yokes. I have seen this caused by a defective vertical output IC and I have also seen vertical problems caused by a small CRT coolant leak which drips onto the main board near the vertical output IC. If you do not have experience servicing the PTK195 chassis than have a qualified tech handle it for you.
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Vertical scan section circuit fault. Check and replace damaged component/s at its vertical scan output section circuit. If you wish to get some details, check the site linked here. Pull up older posts. Check the site in 'Mosaic' view. It will make search easy. http://electronicshelponline.blogspot.com/
the problem is vertical collapse,i am not so sure you can trouble shoot this on your own but you can send the board to eithor pts electronics or tristate module for repair
to get a price get the number off the sticker--left hand board(looking from the back) it will start CTC195---- write down entire number before you call them
Are they thin, white lines running east to west? If so, they are called retrace lines and indicate that the screen settings for the picture tubes is set too high or there may be a mal-function of the CRT driver circuitry. Try adjusting the screen controls which are located behind the front grill of the TV behind an access panel. Once you remove the grill and access panel, you'll see a small control assembly the has two sets of controls. Three for adjusting the red, green, and blue focus, the other, the red, blue, and green screen controls. To adjust correctly, put the TV on an unused input(dark, blank picture) and adjust until there are no visable retrace lines or color in the image.
I can't tell you how to fix this set, but I can tell you that its not a "lamp" issue as this doesn't have a lamp. Its a 3 picture tube projection TV. the three tubes are in a red green blue format, and average about $175 for each one, not including the labor to install them. your problem, may not be the tube, but just a power supply problem, but there is a chance it is.
Sound like you lost Vertical Deflection.Youshould not have a line across the screen because this could destroy the threeCRT Red, Green, and Blue (Picture tubes) if left on to long.There is a protection circuit built in to protect your CRT’s.Check on the PCB-SIGNALboard (Tuner located on this board) transistors Q-206 Collector should be around 1 Volt Base and Emitter 0V. If the voltage atthis point is greater then 5 Volts the Vertical output IC-401 (Mounted on heat sink 7 pin inline IC) is bad, Part # LA7845. Pin Voltages should be PIN 1= 0V, 2= 34V, 3= 32V, 4= 3V, 5= 3V, 6= 33v, 7= -6V. Data sheet located at http://pdf1.alldatasheet.com/datasheet-pdf/view/40357/SANYO/LA7845.html
The lines you saw, i;m sure they are the ones called retrace lines but know the failure could be located on the red CRT board. Most likely the video amplifier is defective and not necessarily the CRT.
What is the model number of your TV?