Width & Focus in DuMont RA-103

[jr_tech]

Originally Posted by Phil Nelson

Looking back at a couple of these photos, now I am wondering whether this CRT was rebuilt.

The sticker on the CRT bell is hand-lettered 12JP4, which made me think "rebuild." But the stamped name looks like it could be Hytron. Would a rebuilding shop use a factory sticker? Or something more like "Joe's Rebuilt Picture Tubes?"

The picture of the gun inside the neck doesn't show any welds or seams in the glass. When you rebuild a tube, wouldn't you leave some kind of visible seam in that area?

It's a very strong tube either way. Just curious.

Phil

But the gun does not appear to be a 12JP4...remember a 12JP4 does NOT require an ion trap, your gun appears to be a tilted offset/ slashed field type which requires a single ring magnet. Why would the factory put the wrong gun in a tube? I suspect that rebuilders often made substitutions when the proper gun was unavailable.

The re-neck seal could possibly be hiding under the yoke or focus coil.

Also, the first letter of the logo on the label does not look like an "H", but instead has a closed top... so I don't think it is "HyTron" but perhaps something designed to look similar.

jr