What were some of the uses the military made of audio/video technology through the 20th century? (select all that apply.) the society of motion picture and television engineers was formed to improve the production of military training films. sony invented the machine-gun microphone for the army to record spy conversations. bell labs invented digital coding in response to the fact that the germans cracked the u. s. analog code. the navy performed the first transatlantic sound wave transmission to inform ships of incoming submarines.