The musician shown here, under the watchful eye of J.S. Bach perched atop her radio, is an early adopter of the electronically amplified guitar. She has a small pickup microphone mounted on the guitar, which is fed into the boosting transformer shown. The output went to the radio’s phono jack, or if it didn’t have one, to the volume control.

The picture to the right, while unrelated, shows a hint that is worth noting. The radio knob had come loose from its shaft. The problem was solved by adding a bit of solder to the shaft to build it up and ensure a tight fit.

The illustration appeared in the April 1940 issue of Popular Mechanics.