Wallace began his media career in radio as a newscaster in 1939 at WOOD-AM in Grand Rapids, Michigan. He stayed there until 1940 and then went to WXYZ-AM in Detroit (now WXYT-AM) where he became an announcer. From there he moved to Chicago, Illinois and worked as a radio freelancer.
After serving in the U.S. Navy during World War II, he announced for radio shows like Ned Jordan - Secret Agent, Sky King, and The Green Hornet.
He joined the CBS Radio Network in the late 1940s as a staff announcer and later was a game show host before moving on to television.