I have zero experience with these and I know I am putting my life on the line, but today I figured I was going to try and fix an old CRT monitor I have. It was only displaying a single colour channel and I figured it would be easy enough. I removed the carcass, grounded the flyback and cleaned everything with pressurized isopropyl alcohol. I figured I had to mess with the neck board (I think it's called) which was fixed inside an iron cage. To do that, I loosened the cage with a soldering iron. I connected the flyback again and turned it on, but now it's hissing very loudly and not displaying anything at all. I can't figure out what I did wrong.