RCA Radio-TV and Electronics 1953-1954
 

"RCA Radio-TV and Electronics in 1953-1954"
"Review...and a Preview"
by David Sarnoff

http://www.bretl.com/tvarticles/docu...s1953-1954.pdf

Wonder what happened to all those color tubes. :scratch2:

Those tubes look like they have a metal shell. The shape is not that of a 15GP22. Are these tubes precursors of the 15GP22?

Maybe the tube experts know what those CRTs are. At first, I thought 21AXP22, which has a metal bell, but those tubes seem to have a slightly narrower, longer bell than the 21AXP22 that was in my CTC-4:

http://antiqueradio.org/art/RCACTC-4...P22Removed.jpg

The 21AXP22 also came after the 15GP22.

Regards,

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

Looks like it could be a C-73547 or possibly a C73293C. I know that the C73293 had its limited production run in 52, but not sure of the C73547 production dates.

Definitely pre-15G prototype tubes. A member briefly had an operational example before the neck cracked, and a Detroit area collector claims to have an under-vacuum but otherwise untested example in a Sparton prototype. Unfortunately his asking price is far beyond what I'm currently willing to pay; I've remained in touch though and we may be able to make a deal before I leave the area. We'll see I guess...