Tube tester suggestions?

[wkand]

There is a test that I have found to be very useful on newer tube types with fragile structures (like multi section miniature and compactron types), called grid leakage, some say grid emission. I believe those to be the same thing. it is a detection of current flow between the control grid of the tube and other tube elements when the tube is properly biased from control grid to cathode. this test could indicate worn out elements in the tube or it could indicate a tube that may be NOS that has been sitting on the shelf for a while. It is not an absolute indication of a defect, but for most tubes, in a properly calibrated tester, it is usually an indication of a worn tube. Sencore TC series (TC162, my personal fav) testers have good circuits for this test. I have a newly acquired B+K tester (from the 1970's) that also has this, but not sure how reliable it is.