Mystery Soldier

This is Photograph 111-SC-282168 U. S. Fifth Army Mobile Unit Programs Can Be Heard over Razor Blade Sets. 1945. Records of the Office of the Chief Signal Officer, Record Group 111. National Archives at College Park, College Park, Maryland. It is by far the best known photograph of a soldier with a foxhole radio at Anzio. It was taken for YANK magazine but never ran. 


The other photos in series with this one include the names of the subjects. But not this one. The note with the negative only gives the title. So far this soldier remains anonymous. I would prefer to include his name in the book, naturally, so if anyone recognizes him please let me know!

Emergency Crystal Detector

Razor blades were occasionally used to make radio detectors even before the invention of the foxhole radio, though not in the same way. This one, from the June 1925 issue of Radio News, uses two blades mounted upright – not the safest configuration – which are straddled by a chunk of "coke, carborundum or pyrites". The contact between the blades and the mineral function as a demodulator of radio waves.

It isn't exactly a foxhole radio detector, but it does show the same sort of improvisation that would lead to the razor-blade-and-pin detector. The Radio News detector more closely resembles a "microphone" detector, which either used a piece of steel – like a sewing needle – straddling two sharpened carbon edges, or else a small piece of carbon straddling steel edges. It is called the microphone detector because it resembles the microphones developed by David Edward Hughes in the 1870s. Hughes also discovered that his microphones could detect electromagnetic waves, though his findings were initially dismissed. The microphone as a detector of radio waves was more common in the early 1900s than the 1920s.