I have a pair of RCA (Radio Corp. Of America) JAN CRC 12sn7GT..one is 1943 the other is 1945. The coolest part about these 2 is I have the original boxes..& all sides & flaps are pretty much intact. Order & contract # printed on the box. Long list of patent #'s provided on the inside folded sleeve that holds the tubes. U.S. ARMY U.S. NAVY wartime tubes man. I use these in my DIY 12/6sn7 preamp.
I also have a pair of 1944 RCA JAN CRC 5R4GY rectifiers with the Double slanted getters. I switch one of them in & out in my Icon Audio preamp that is pretty sensitive to rectifier changes.
I grew up working with my Grandmother that owned 3 Antique stores. I've always found old stuff to be pretty cool. When I was a young teen in the early 80's I would come across lots of vacuum tubes & electronics when we would do estate sales. Old people would pass away & my granny would get hired to go through these houses to price out & then sell the contents over a few days to the public..also having 1st pick of what she wanted. I had no idea what I had access to then. But to be fair tubes were still very cheap back then. Had I known I would have been hoarding tubes & radios from an early age.

