Signal Corps. US Military Issue I-177b

I-177b Tube Tester. Signal corps. military issue i-177b tube tester amazing quality imageTube tester schematic and circuit image high quality image tube tester hickok tube tester for tube testing hickok tube schematic

The Schematic shown above is riveted to the inside bottom of the steel housing that protects the circuits and components.

Click to enlarge the image and press ctrl + to zoom in further for a closer look.