On worldradiohistory.com can be found "RCA Review" magazine. This quarterly publication tells what has been going on at RCA.
See January 1937, starting on page 111.
The 6E5 is thoroughly discussed with several schematics and charts, and 3 pages on the type 913 1" CRT are also presented.
https://worldradiohistory.com/ARCHIVE-RCA/RCA-Review/RCA-Review-1937-Jan.pdfThey have all the RCA Review issues online from 1936 to 1985.
