15GP22 Color CRT
The 15GP22 was the first production color picture tube, made in 1954. It was used in the RCA CT-100 and most other 15 inch sets made in that year. The CBS 15HP22 was similar, but easier to manufacture. The 15GP22 was quickly replaced by the 21 inch 21AXP22, which was used in the 1955 model sets. Here is an article about installing this tube.
These tubes suffered from a leakage problem, and most of the surviving tubes are full of air. Since 2008 there have been a number of attempts to rebuild the tubes and solve the leakage problem. John Folsom and Bob Galanter worked for months with Scotty at Hawkeye and were ultimately unsuccessful.
In 2010 RACS, a French company, successfully rebuilt a 15GP22. That tube is still working in a set at the museum.
Based on that success, a number of tubes were shipped to RACS. However, they have been unable to reliably seal the metal ultor ring using frit.
John Yurkon has undertaken a project to eliminate the ring, and to make an all-glass 15GP22.
Courtesy of Dave Arland
Tele-Tech, February 1954
New Era, January 1, 1954
Popular Science, November 1953
Thomas Electronics brochure
Courtesy of Dave Corbitt
Courtesy of Rich Mensinger