Book excerpt: When amateur enthusiasts began sending fuzzy signals from their garages and rooftops, radio broadcasting was born. Sensing the medium's potential, snake-oil salesmen and preachers took to the air, at once setting early standards for radio programming and making bedlam of the airwaves. Into the chaos stepped a young secretary of commerce, Herbert Hoover, whose passion for organization guided the technology's growth. When a charismatic bandleader named Rudy Vallee created the first on-air variety show and America elected its first true radio president, Franklin Delano Roosevelt, radio had arrived. Rudel tells the story of the boisterous years when radio took its place in the nation's living room and forever changed American politics, journalism, and entertainment.