The photo that I pasted is not the "A" tube.
When viewed next to a 21FBP22, the brightness is much less.
THe FBP is in a 1961 CTC 11, original tube.
I have a CTC7 (Anderson) that has the 21CYP22A, with a 1961 date code. The brightness is not that great on that tube either, although the emission is good.
I have a 1964 21FJP22A Hi-Lite that has cataract, but great emission. I am going to remove the faceplace (thus making it a FBP, and put it in the CTC7. I will take before and after digital photos to see the difference. I will post them for all to compare.
Kirk Out
