A US Army 1st Signal Brigade soldier operates a signal data machine RD-304 at the Regional Communications Center in Vietnam.

A US Army 1st Signal Brigade soldier operates a machine at the Regional Communications Center in Phu Lam, Vietnam during the Vietnam War. The soldier loads a tape into signal data machine RD-304 and starts it. The machine in motion. A close up of the tape reel turning. A soldier at a maintenance console. He pushes buttons and a light flashes.