Here is probably one of the rarest color CRT's you'll see. It's a prototype RCA single gun color CRT, notice the date - 1951.
BTW: It is filled with air.
For more information on the CRT, (and see the surprise surrounding the tube) go to the ETF web site:
http://www.earlytelevision.org/rca_d...al_onegun.html
The tube will be donated to the ETF museum, and be on display for the 2008 convention.
Chuck