This is also the name of a very funny science fiction novel written by Eric Frank Russell (also known in the US as "The Space Willies").

A space scout, during an interstellar war, is stranded on an enemy planet far from the front and captured. How can he win the war with just a piece of copper wire and a block of wood? You'll just have to read the book to find out (if you can find a copy).

It is expanded from an original novellete "Plus X" published in Astounding Science Fiction in 1956.