There’s still a mystique around vacuum tubes long after they were rendered obsolete by solid state devices, and many continue to experiment with them. They can be bought new, but most of us still come to them through the countless old tubes that still litter our junk boxes. But how to know whether your find is any good? [Rob’s Fixit Shop] took a look at a tube tester, once a fairly ubiquitous item, but now a rare sight.
This is a companion discussion topic for the original entry at https://hackaday.com/2024/02/08/a-tube-tester-laid-bare/