Fifty years ago, the “Beginner’s Corner” of the November 1966 issue of Electronics Illustrated carried three circuits for basic radio receivers. The first was the crystal set, the second added one stage of audio amplification, and the third was this basic regenerative set.
The tuner was a ferrite loopstick coil, which were available in abundance for experimenters to use in similar circuits. It used permeability tuning by moving the ferrite core in and out. The tickler coil was added on as a winding around the outside.