Originally Posted by Frick
The normal thing to look for is bad caps, failing solder joints and stuff like that. The fact that it used to work if youy smacked it around a bit indicates that there might be as simple as loose cables, parts or joints. CRT's are pretty cramped so it might be hard to spot. But look very carefully.
Yeah the good ol thump. CRT's are well known for their dry joints too, although if you plan to fix it your self make sure you discharge the tube 1st or else you be in for a nasty ( not deadly ) shock lol..