Just because there was a war going on didn’t mean that you couldn’t listen to the radio while riding your bicycle, as shown in Popular Mechanics. December 1943.

The set was billed as a “big town” bike receiver, and the article pointed out that it would pull in the local stations “as you ride around in any city where powerful stations are located.” The set itself was just a crystal set, using a fixed detector. The set was mounted in a tin can, which in turn was afixed to the bike. The tuning condenser and headphone connections were conveniently accessible while riding, and a whip antenna was used to pull in the strong local signals.