Just how bad can an Ion burn be?

[Tubejunke]

Originally Posted by Notimetolooz

I did occur to me that the ions would be hitting the wall in a bent gun tube and since the ion trap magnet isn't strong enough to effect the ions much, they would never reach the screen. Even if the trap was mis-adjusted. I remember seeing a picture. maybe in that same book, of a gun element with a notch in the side of the aperture, produced by electron bombardment from a mis-adjusted trap.

Hence the reason why the traps used to be called beam benders by techs or engineers. This is a good thread, but I'm still left with a question that's been in my mind for many years, but never really needed answering as I never burned a tube. The procedure I have always used (I forget now where I learned it) is to set brightness to a mid level with the magnet in approximately the correct position (over the split/gap in the gun) and rotate for max brightness. Then move slightly back and forth again for max brightness. Sometimes corner shadows require retouching of the magnet. I assume that maladjustments that produce burn must be if the magnet is adjusted for anything but max brightness. I never have taken a chance on that and always work fast when setting one.

Here's another interesting topic that I don't believe is covered here. What about the double ion trap magnets. A crt such as a 10BP4 calls for one. I have an RCA 8T 243 (that I am trying to get rid of) that I got with a 10BP4 and it had a single trap. It did produce a raster, but reading data on the set and the tube told me that it needed this double magnet, so I found one thanks to the Internet and possibly this site. Before the WWW, it would be almost impossible to find such an item. Anyway, it's still there and I never finished the set's slated restoration. I think I will snag the trap when I find a home for it. I will of course inform the new owner who will still be getting a heck of a deal. Point being, I never knew and still don't know what the double magnet does that a single doesn't and why some tubes call for one and not the other specifically. I bet there are a bunch of BP4 owners here that are running on a single trap with no problem.