This CRT is a Hyundai HN-4850, sold under the brand name KTX. A while ago, I fed it a video signal at a greater frequency than it was designed to handle, and after a spell of cutting out, jerking image, odd 'crack' and 'Fzxzsxch' noises, it stopped working altogether, and only made a repeated click sound, and the amber standby light flashed. I looked up the issue, it appears to be caused by a bad Horizontal Output Transistor (HOT). I ordered a new one, but in the meantime I found another CRT, and installed its HOT into mine. It made the same noise it used to, (the "Fzsxcxsh" sound) and the same weird white flash at the edges of the screen, before going back to the repeated clicking and flashing. Clearly the HOT was only a casualty suffered as a result of another bigger issue somewhere else. Could anyone tell me what the issue might be, and how I might be able to fix it?
I get the impression that you're not a trained monitor or TV set technician with CRT experience.
I can only recommend to stay away from the circuitry inside a CRT, as there are deadly high voltages (way higher than line voltage!) inside, even minutes after switching off.
Your life is at risk, really!
So, if the CRT is worth it, get an old-school technician to do the necessary repair. But probably you're better off looking for a replacement.