[ohohyodafarted]

RCA 2000,

You ask many questions but here are a few answers.

First, the 15GP22 was never successfully rebuilt by anyone except RCA. Guns were not available. RCA had the only source. Anyone else that tried to rebuild this tube used a standard 21" roundie delta gun which did not provide for electrostatic convergence and was not a compatible rebuild.

RCA made the only production run of these tubes for general availability. Some other manufacturers "experimented" with limited experimental prototypes, but never put anything into production. As for the machinery and equipment that was used, I am sure it has all long been scrapped.

"Or...were these tubes GARBAGE from the beginning for RCA and did only one out of maybe 10 of them made actually work, for any length of time? "

The answer to your question is Yes, sort of. I will explain what I mean....

At the time these tubes were made, RCA was forging into new territory, and they were under a lot of pressure from the government in meating deadlines to demonstrate the viability of a "compatible all electronic" color tv system. In order to get the federal government to approve the RCA system over the CBS system, RCA had to demonstrate it's viability. So RCA was in a mad race to get something out to the public.

So they had to do whatever they could to produce a tri color crt in record time. As a result they drew on whatever methods and technology they had used in the past. There was no frit glass at the time so they could not make a two piece crt out of just glass. There was no way to join a two piece all glass crt. The 15G had be made in two pieces so you can install the shadow mask and phosphor dot plate inside. Photo deposition of phosphor dots had not been invented at the time the 15G was produced. That came the following year invented by CBS. And all glass color crt's did not come into existance until 1957 with the introduction of the 21CYP22 in the CTC7 series, when frit glass became available.

So the only way to join a two piece glass crt envelope together was to fuse the front and rear glass sections to a metal ring (bonding glass to metal was a perfected technology) and heli-arc the two metal rings together. There are more issues to deal with that I will explain in my presentation at the ETF.

But sufice it to say that the 15G was a "Rube Goldberg" style picture tube...IE: it was a complicated solution to a problem.

All you guys need to come the ETF convention and view the presentation. There will also be a number of touchy feely show and tell items that will be of interest.

See ya all there,

Bob