Roy Trakin Longtime record promotion executive Jonas Cash, who founded the influential radio programming competition AIR (Active Industry Research) in Baltimore-Washington, MD, died at age 81 in his Columbia, MD home.“He was not just a promotion executive, but a real artist development guy,” says veteran promotion/marketing exec Michael Plen, who recalls how Cash helped him break Wall of Voodoo’s “Mexican Radio.” “If he believed in a record, he’d go all out.”AIR established competitions for