Have a look at what he did in the video below. The tester is just a few resistors, a tube socket, and some bench power supplies. Of course, you may have to adapt it to whatever tube you are testing.

Most solid-state replacements are plug-and-play compatible with standard tube sockets. However, it’s crucial to check voltage and amp specifications to ensure compatibility, especially with ...

When we yanked the dipstick tube, you know what happened ... We grabbed a 3/8” drive 7/16-inch deep-well socket that fit into the rubber seal quite nicely and immediately stopped the leak.