I just had to RMA my regular monitor so I pulled out a really old KDS 19" which is having problems and an even older 17".
Specifically the picture starts to dim and in maybe 10 seconds goes completely black.
To get the picture to work again I have to pick it up and tilt in onto its side. Sometimes I can then use it normally for the rest of the day, sometimes I have to tilt it again after a few minutes. Sometimes I just leave it on its side.
When its upside down I can get it working again simply by shaking it side to side.
Anyone ever work repairing CRTs? I imagine that something is lose inside and could be easily fixed if I knew exactly where to look.