My 20 year old Sony Trinitron has developed a problem. The picture is getting cropped at the sides, as if it's too big for the screen. Other than that it's seems to be as good as it was the day I first got it. Because of it's age I rather not invest in profeesional repairs, plus, it would be a real hassle getting it out to a facility. Is there anything I can do on my own without getting electrocuted?