Vertical sync problem

I am not aware of this model having the pip bypass procedure . Older models Yes . I have though seen some of these sets were the picture tube leaked onto the cicuit board causing this problem. With the tv unplugged and the back removed , Use a flash light and look at the board on the left to see if there is any liquid on this board . It is usually below the metal brackets where the picture tubes are mounted . Sometimes you can swipe your fingers on the under side and fill the fluid coolant . Then look right below that area and you'll see it on the board . Use paper towels to dry up well . Then plug back in to see if your problem is resolved. Now if it leaked that is telling me your seals are leaky and need to be replaced and coolant added to that picture tube that was the problem . This can be very tricky to do . If that was your problem call around to get your best price to repair your set without them telling you , you'll need to get the picture tube replaced . Good luck