KDKA in Pittsburgh was the first to nationally broadcast a live fight and Jack Dempsey did help radio immensely. However, it was the Dempsey-Carpentier fight in 1921 that was first broadcast, not the Dempsey-Willard fight from 1919. Interestingly, Dempsey won both in the fourth round.
Although the story takes place in 1919, and the years immediately following, all of Alice Faye's clothes and hairstyles are strictly in the 1941 mode, as are also those of Mary Beth Hughes and the other female members of the cast; the musical arrangements of Faye's featured songs are also in the contemporary 1941 style.
When Rix Martin (John Payne) first sees the radio equipment Chuck Hadley (Jack Oakie) has set up in his room, he thinks it's a still for making bootleg liquor. But the scene takes place in early 1919, before Prohibition had taken effect.