There’s still a mystique around vacuum ... 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 ...

There’s still a mystique around vacuum ... 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 ...

The video explains the operation of the vacuum tube, specifically the triode, which is essential in modern communication devices like radios and telephones. It describes how a tungsten filament emits ...