Seventy-five years ago, the new serviceman learning how to fix radios could very well have done so in a classroom with this demonstrator at the front of the room. From the 1946 catalog of Concord Radio Company showed this working “All American Five” radio, layed out for instructional purposes. The circuits were easily accessible from the rear, so faults could be demonstrated by shorting out critical parts. The trimmers were all accessible from the front, so that alignment could be demonstrated.