Early Electronic Television
12 Inch WW2 Radar Tube
This CRT was built in a shell identical to the 12AP4 and was made by RCA for an early radar system. The gun is different from the one in the 12AP4. It is located about two inches closer to the screen, and the elements are different. The phosphor is similar to P7, with a short persistence blue and long persistence yellow.
This tube was probably used in the AN/TPS8 ground radar system supplied to the military in the early 40s. There is a description of this radar in the book "RCA's Contribution to the War Effort Through Radar 1932-1946", published by RCA. It describes a magnetically deflected tube with long persistence phosphor, using a yoke that rotates around the neck.
Here is the display unit from this radar system. The tube appears to be the proper length for a 12AP4 shell
Courtesy of Bob Dobush