I have a 4500+ that is giving me grief. I just replace the Dallas chip as suggested by helpful folk on this forum. Last night I turned the PJ on to watch a movie and noticed that the red tint seemed to be blicking on and off. The red begin blumming also. I noticed that the red crt was alternating between dim and bright. The convergence also shifted. I ended up moving the whole red grid to get it back in convergence. Now the gun is dim. When I put up a test pattern, the verticle lines are fat. I can see them faintly on the screen. The horizontal lines can not be seen on the screen but can be seen when looking through the lense. I own a working 4501 that I can have swapped parts out of before. The 4500+ has new model crts and netboards. Are these interchangeable? are the HVPS and LVPS units interchangeable?