Originally Posted by fernan1234
Do any of you think that a manual degausser could help with his green blob problem at all, or would it be not worth the risk of making it worse?
I ask because I have a similar problem with a 34HS420.
I would strongly advise against it. There are some definite risks involved in doing something like that on the Sony TVs. The manual degaussers produce a stonger magnetic field, which can effect the fine mesh of wires which make up the aperature grille on the Sony Trinitron tubes. So the "cure" could end up creating more problems than the disease.
Some comments about this from the CRT Repair FAQ
WARNING about degaussing late model Sony Trinitron CRTs...
...You should NEVER use a big degauss coil on ANY SONY WEGA tube, or ANY SONY 27" or larger CRT made after 1997. Sony deliberately put a small amount of magnetic field into the strapping and aperture grill to compensate and improve the convergence. A BIG degauss will remove this and make the tube look very bad...
...I NEVER use the large degauss coils on the Sony tubes after seeing the Sony video of how CRTs have been damaged...
...Note that Sony tubes do NOT have shadow masks, but they have aperture grills which are an array of incredibly fine wires under tension. A BIG degauss coil can also rip the aperture grill away from the stabilization wires.
I don't remember if the 34HS420 has an aperature grille or shadow mask, but I'd advise against using the manual degaussers in either case because the shadow masks are made of metal as well, and could also be adversely effected by a strong magnetic field (especially if you don't know what you're doing).
The CRT Repair FAQ, also suggests waiting at least 20 minutes
between power-ups to give the degaussing coil time to cool down, so it it doesn't overheat. I know people here on this forum who have ruined their sets though by repeatedly turning them on-and-off without giving the degaussing coil or power supply some time to recover/cool down. So that's why I recommend against doing this to try to fix the problem. If the source of the field has been removed, then IMO the impurity should eventually dissipate with normal use.
However, as I alluded to above, the TV could also be holding more static charge than normal in it's tube or frame around this time of year, and it may take some time for that to diminish.