Eric J Korpela wrote: the problems with CRT's will be -gassing -settleing of debris from inside (or phosphor) -potential rot of impace shield on front, or adhesive. -deterioriation of the components -residual charge To minimize gassing, there isn't much to do, other than to care carefully for it, obviously don't break it. There are inorganic materials added to the vacumn vessel before it is sealed that absorb oxygen, and nitrogen, that is about all you can do for the duration. I know that cesium was used at one time, but I don't know if that is still the norm, or if it has been replaced with something else. Bottom line though when it quits doing its job over time absorbing outgas, you are pretty much going to have to toss it or rebuild it. Store it with the face down, or at least not with the electron gun down. I guess it could be argued that debris could settle on the front and damage the phosphor, but that is less likely, as there are less things for it to adher to on the front where the phosphor is, than in the electron gun section in the neck, plus the obviously larger target. the things I have seen that are bad is when the adhesive to glue an impact safety shield on goes. There has been discussions you can search on this list , rather than repeat here about that. The last thing I would worry about is to be sure that the drive electronics are not bad when you restore it to service. that board may have decayed electrolytics and high voltage components that might arc and damage the electron gun guts after a long period of storage. The last thing is unlikely to occur in computer monitors, as I think most have ways to loose charge and not accumulate it over time. older crt systems would potentially accumulate charge internally and that could damage the phosphor, or the electron gun end over time by attracting contaminates to cover the electron gun.

On Monday 08 May 2006 01:38 pm, Eric J Korpela wrote: I read somewhere not all that long ago that leaving vacuum tubes of any sort sitting idle for long periods of time will tend to result in them getting "gassy", by comparison with operating them from time to time. OTOH, a CRT is going to wear eventually in terms of cathode emissions, a problem that's going to be worse at high current levels (high brightness) and also in some cases you'll have burn-in on the screen to deal with, though that's easy enough to get around. So I'd say that the solution is to run it from time to time, gently. -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, a critter that can be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin