The young man shown here is pulling in the short waves thanks to a simple receiver designed around wartime parts shortages. The set used three tubes, which could be types 30, 199, or 201-A, obsolete tubes used by older battery sets. It featured two stages of audio amplification, and could drive either headphones or a small speaker. It pulled in shortwave signals from 160 to 10 meters with homemade plug-in coils. The detector was regenerative, with a variable capacitor controlling regeneration.

If B batteries were unavailable (a likely scenario given wartime shortages), then the transformerless battery eliminator shown here could be used.  The set appeared in Popular Mechanics 75 years ago this month, November 1944.