Charles--thanks!
I've sold a couple of the early 15GP22 prototype CRTs over the years, the style with the bolts showing through the mask. And at least one of the 15" prototype TVs.
Kevin--thanks for the 19TP22 designation info.
This was the first time I ever heard of it, so like you, I suspect they never went into any kind of production, and if they made one or two prototypes, it was a lot!
Harry
PS--for what it's worth, I did find a little on Pete's page about this CRT...if you do a Find in Page: 19TP22, it'll make it easy to spot!
http://home.att.net/~pldexnis/potpourri2/lastpage6.html