I was searching for a few schematics that used the 01A tube just to see how it was traditionally operated. I hit the jackpot, never saw this site before. Big manuals of just about every radio built then. These volumes cost $7.50 each in the 1930's that would be $125.21 in todays dollar. Apparently only serious repair shops would have laid out 125 bucks during the depression for each volume of a 24 volume set like this. Good reading.
http://nucow.com/120,000FREE.htm
http://nucow.com/120,000FREE.htm