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Photos

Snapshots of what’s happening in the Defense Department.

A soldier holds a crude radio.

Foxhole Radio

A soldier holds a foxhole radio — a crude crystal radio — at the Anzio beachhead in Italy in 1944. Soldiers were not allowed to use vacuum tube radios because they radiated radio waves that could be traced by the enemy. Instead, soldiers built crude crystal radios, which were safe. A common form, like the one in the photo, used as a detector a blue steel razor blade with a pencil lead pressed against its surface by a safety pin.

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