RCA 21CT55 B8802897 is Alive!

[Tomcomm]

Originally Posted by miniman82

The FBP/FJP tubes have an orange-red color to me, while the earlier ones were closer to actual red. Placed side by side showing the same color bar pattern, my CTC-7 with CYP tube gets closer to actual red than the later Philco with FBP does. Since I just got a good AXP for the CTC-4, I can confirm that the AXP gets even better (what I would call more accurate) color than the CYP but at reduced brightness.

Sometime in the future I'll be doing a full writeup of all 3 tubes, so people can see the actual differences. It's slight, but perceptible.

To be truly objective, you must include the gray screen 21FBP22A rare-earth. I wonder how many VK members have operating gray screen 21FBP22A's? Hopefully they also live near you and are willing to participate. How many flights of stairs did you say you had, three as I recall. LOL!

In the meantime I would like you to retake and post the 3 tv cluster pix you have. This time put the Sony closer and adjust the TVs for most accurate red and white color bars. Also pull-in to include only the TVs and shoot in total darkness. I have been playing with the color balance feature of my Photo Impact graphics program that reads the RBG values 0 to 255 of any spot on the JPG image. This is the hacker's approach to chromatic spectrum analysis but should give quantified data on relative phosphor differences of all your CRTs.
Thanks for your interest and cooperation.