There’s a good reason why this young man dressed up to go ride his bike. That’s because its basket contained a four-tube radio capable of providing loudspeaker volume on local broadcast stations.

Because of its nondirectional characteristics, a four-foot rod antenna was used. Grounding was necessary, but an attachment to the bicycle frame provided an excellent counterpoise.

The set featured a DPDT key-lock switch to keep curious onlookers from running down the batteries. The magazine also advised locking the set to the basket or bicycle frame. The set used three 1N5GT tubes as RF amplifier, detector, and the first stage of AF amplification. A 1T5GT served as final AF amplifier to drive the speaker.

The set appeared 80 years ago this month in the April 1940 issue of Popular Science.