This Murphy V2015D has been mentioned before. To recap, it was extricated from a friend's garage as he wanted rid of it. The case is tatty but the crt is a corker. Unfortunately it showed the classic problem of a raster that after a few minutes use grew dimmer and 'blew out'.
A prime candidate then for the now tried-and-tested method of overwind revival. This was duly done with the inner core being wound with as many layers of Kapton tape as possible. On reassembly I was greeted with a nice bright picture of ample width, which looked set to hold steady. Alas, it was not to be. After a few minutes there was a nasty internal arcing noise from the LOPT and the raster disappeared. No physical signs of distress could be seen around the LOPT and the overwind was cool to the touch.
Once the set has cooled, the whole performance is repeated. Nice bright raster, then after a short time we're in trouble again. A close monitoring of events reveals sounds of faint fizzing within the LOPT after a few minutes. This grows a little more intense as series of white dashes dance in a vertical line on screen about a quarter of the way in on the left of the picture. The comes the sudden breakdown with the raster vanishing as the LOPT squeals and crackles in protest. There is a distinct smell of burning, so something really isn't happy.
There's nothing for it but to whip the LOPT out again and pull it apart to see what may be happening. Meanwhile any thoughts would be welcome!