(1) Tested Strong Motorola 19AU4 Tube.
Date Code 5727.
The base has a very fine hairline crack in it - see photo 4. Obviously this doesn't affect performance - see test result below.
Tested on a calibrated Hickok TV-10 military tube tester and exhibiting no shorts at 1350 where 800 is minimum pass/good.
~ Please view all 4 photos ~
