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 ...

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 ...

There is nothing simple about a good vacuum tube tester. In fact, most tube testers were very complicated to set up for each different type of tube to be tested. Testing a quantity of different tubes ...

Marked: "DAYRAD Tube Checker / Mfd. by the Radio Products Co., Dayton, Ohio. / Licensed Under Weston Patent 1704566 Type B". Includes leather carrying strap. Tube tester designed for A.C. plug in ...

Marked: "Sterling Type R-511 / Tester for AC & DC Tubes / & DC tube reactivator. / A.C. Volts 115 Cycles 50 / Serial No. ____ / The Sterling Mfg. Co., Cleveland, Ohio ...

In 1904 John Ambrose Fleming invented the first vacuum tube, called “the Fleming Valve.” By the mid 1920s, tube radios were becoming mainstream, creating a need to easily test vacuum tubes. The first ...