Interesting dilemma. I presume you claimed for it, and want to see if it’s fixable anyway? From the pic and your description it’s certainly a purity problem, possibly caused by damage to the aperture grille, or perhaps by the fact it’s been moved around. If it is damaged, you might not be able to get it looking ok again. One important question to begin: are you in Australia, and was the set originally/shipped from Australia?
First of all, do you have access to a more powerful, external degaussing coil? I doubt it will help, but it’s worth a shot. There a few things to try after that:
After that, or anyway, go and get some magnets and try them around the top edge of the bezel, externally. Anything will do to start as long as it’s more powerful than a fridge magnet. Officeworks have some, or Jaycar. If this seems to help, grab more magnets online for cheap if you need to. Something like these -
https://magnet.com.au/neodymium-disc-10 ... gJ3ZPD_BwE. If the grille is actually damaged, and/or if setting up the tube again doesn’t get things perfect, you may need to try this anyway. You can try sicking a few magnets around the tube like is shown in the setup procedure below as well, which will be more effective, but this will need to be done with the set running so be careful. Be aware that very strong magnets, like something from a subwoofer, might pull the grille out of shape permanently, and I would guess this is more likely if the grille has been damaged. Hell, you might even be able to pull the grille back into shape, but I’d save that for a true last resort.
If the magnets fix everything, you can leave it like that. If they don’t, the next and most complicated option is to try setting up the tube again. The procedure is described starting from section 3-1 on the service manual -
https://www.manualslib.com/download/128 ... 8042q.html and you will likely have to do up to section 3-4. This video might also help -
https://www.youtube.com/watch?v=Gmrrf5hiYQI. In fact that’s a good one to watch to give you an idea of what might be happening. Be aware that there are dangerous voltages around a CRT, and the deflection yoke itself has 1kV across it. It’s not easy to zap yourself, but if you’re going to attempt this, be careful.
Third, you might try leaving the set upside down, with the green corner corrected by a magnet or two. If you can’t flip the display via software this will mean breaking the yoke connector in half and turning each part around. This will rotate the raster scan by 180 degrees, flipping the display horizontally and vertically. This trick is often done on arcade monitors to minimise the noticeability of screen burn. Take a look at pdf page 95 of the service manual linked above, because mixing up the horizontal and vertical coils will destroy the deflection circuitry. If this works out, you could mount a small fan somewhere on the case, because heat might not be able to escape.
Those are the ideas that come to mind immediately, but someone else might have a better one.
EDIT: I guess one problem with any of the above might be that if the grille is actually loose, the fixes might not stick if it can move around. If you have the set running right way up, and rock it to the left and right sides, do the colours change much? IF it makes a slight metallic ringing sound and the colours change noticeably with only a little rocking, then yeah, the grille probably isn't good. Which is the question you were actually asking - seems i felt like writing an essay, lol. You can still apply the magnet fix above though, and see how it goes.
EDIT2" Now I've thought a bit more, you might try reseating the connectors inside the monitor. That might have been causing the inputs not to work.
