Our set was purchased in 2001. In the last month
Hello
You are saying about vertical retrace lines. Thes lines will be thin and spread all over the screen at about 1 inch aprat or so, little slanted in position. There are mainly two reasons for this fault. One is vertical output Ic and its supply related. Second is related with increase in screen voltage.
You just open your TV,and adjust the screen voltage a little less, by the help of screen voltage adjuster reistor. It can be located on the picture tube base card, diretly soldered to it. If it helps no need to do anything. After adjusting the scren voltage, increse the brightness contol a little and see whether the lines are there or not. If not it is ok. If yes, you have to go to the vertical output section of your tv. Any screen voltage adjustment should be done after decresing the brightness, contrast and colour controls to its minimum. At this condition you will only see the display items only. Screen voltage is so much related to picture clarity. It must be done in a dark circustace.
If it doesn't help, that is even after the lines are there when you increase the brightness, locate the vertical output section of your TV. It will be normally on the main board, and there will be an ic for amplifying vertical sweep signals. If its supply voltage has some trouble, this type of fault may occur. As your Tv is abot ten years of age, it is quite natural, that most of the capacitors has gone value detained. It is best for you to change all the capacitors, at about 14 nos of them at the same time, as it will cost not much. Change all the capacitors around the vertical output ic is best, as you can't measure the exact value of capacitors, without a capacitance measuring meter. Also look for any bad, or loose soldering is ther to the pins of the vertical Ic. Resolder all the points around and with it by applying a little more solder. This will retify your problem. Ok