|
I've never seen a way to remove it. I would be worried about dislodging the shadow mask if you try too hard.
Sometimes it's material inside the tube sometimes it's a manufacturing defect. CRTs were graded A,B,C,D etc. I think the grade C or D were often etched TEST TUBE on the face and installed in repair shop test jigs for console chassis hauled in instead of taking the whole set.
|