Hissing TV.

I actually tried white spirit first (alcohol) but I don't think it was that good so I used just water next, maybe with some washing up liquid in it. I know tobacco smoke deposits seem to be very water soluble.

Water is a good solvent. Some tars won't dissolve in ethyl alcohol but most will in isopropyl or methyl alcohol. Personally I would have started with testing a small area using a dab of Acetone on a rag. If the surface seemed to tolerate that well then I would have wiped around the anode cap for maybe 50 millimeters then the cap itself provided it too was silicone rubber as Acetone doesn't react with 100% silicone rubber readily.

Sure you do. It's quite toxic that way. i've seen it set on fire when people didn;t let it cure overnight. they would apply it, then power up the TV an half hour later to lots of smoke, and some flames.

Not IME. Tobacco smoke is very tarry. I always use pure alcohol (metho) on a cloth to remove smoke deposits.

Well...switched on this morning and.... no blurry picture!!!

However it was hissing a bit, I can't see no arcing however it's hard to see with the back on, the hissing seems to have stopped now.

I thought putting the back on would help, I think the same happened with my last TV but I can' remember clearly. It seems to me it is effecting the capacitance in some way or whatever.

I an not sure about all this flyback stuuf and how it works and why the tube is involved. Is the tube used as a smoothing capacitor?

Regarding solvents I know water works because I have to clean up smoke deposits else where and I just use water and maybe some detergent., with white spirist everything smells of alcohol.

Well I can't remember when reinstalling a TV back sharpened up a focus problem but I guess I've not seen every little oddity.

Well all the evidence I have seen is that it does!! It was fine this morning, it hiss a bit but that has dissapeared totally.

I am tempted to take the back off again and see what it is like when it fires up in the morning, however I don't think I have done my back any favours lugging it up and down from it's normal resting spot.

I can perhaps see why it would cause a difference to the capacitive characteristics of the tube, particularly if the back is covered in smoke deposits. I have a feeling I had the same with the old set, that is why I mentioned it before I tried it I think.

Well maybe in the name of closure but I think it's best to leave sleeping dogs lie.

deposits.

If I recall the focus grid on a larger CRT is upawards of 200 volts. It's just hard for me to vision the back of your tv effects the focus, And I've seen some focus adjustments that were not accesable unless the back was removed. Oh at least you've got a watchable set for now.

Very true, there is certainly no focus adjustment visable with the cover on. Maybe I will give it a test some time but I will leave it for the moment.