Picture tubes--rate them...

[dieseljeep]

Originally Posted by Electronic M

The 15G was on par with the 21AXP and metal cone monochrome CRTs of the 50's as far as reliability goes. Why the 21AXP is harder to find than the monochrome tubes and the 15G harder to find than the 21AXP ultimately comes down to how many of each were made.

Also I have seen one (and heard of some other) 21FJP tube going to air without being necked so those tubes are not completely leak proof either.

You over look the fact that the Japanese beat our 23EGP to market with their own tube (the number escapes me at the moment).

Performance wise it is dependent on phosphor color rendition (the round tubes especially the earliest ones have it hands down in my opinion) and the electronics driving the tube. Most roundy tubes I've seen run tend to have soft focus, but on a CTC-4 (with a 21FJP retrofitted in) and a Zenith roundy I got last year the focus and video circuits drive the tube to have a monochrome picture with detail sharp enough to rival my Zenith Chromacolor.

Tom! You're thinking about the 15" CRT, with the roundie neck. Toshiba built the set and CRT.
Motorola started building the TS908 with the 23EG in late 1963. In fact, the first models didn't have UHF, as required after May 1964.
IIRC, the Sears rectangular 15" was considered to be a 1965 model. RCA came out with their CTC17, using a 25AP22 in spring of 1965. It had a CTC16E knobs and control panel.