Many thanks to SWLing Post contributor, Mike Hansgen (K8RAT), who shares the following film by RKO Radio Pictures via YouTube.

Click here to watch on YouTube.

Here’s the film description:

Made during WWII by RKO Radio Pictures, AIR WAVES gives a brief history of the radio, and shows the development of the technology as it progressed from a crystal set novelty to an indispensable part of American life. Radio City Music Hall and the Rockefeller Center are seen at the 2:00 mark, with the largest radio studios in the world. At 2:30, the NBC studios are seen and at 3:10 a demonstration is made of how sound effects are made using cellophane, wooden blocks, and rubber spheres. At 4:10, a studio is seen with actors rehearsing their lines, and an engineer working with the actors to make sure everything is technically okay. At 5:41, announcers Milton Cross is seen with Jack Costello and Calvin Keach. “Twin gods of radio broadcasting are the clock and the conference…” says the narrator, and at 6:00 you’ll see the discussions that lead up to the broadcast of any network show on radio (and today, on TV). At 7:15, records are played on the air, scripts are produced on steno and mimeograph machines, and all sorted… The music library is seen at 7:48 with sheet music laid out. At 8:06, all stations are notified of the latest information with the new program and a dress rehearsal undertaken. The stopwatch commands the attention of everyone, and the program is finally on the air at the 9:10 mark.

At 10:00, the film dramatically shifts to show December 7th in Hawaii, and speaks about the work of NBC to sell war bonds and promote national defense and “do its share unflinchingly”. The war effort is shown with men and women working on the air to help people working “at war” and boosting their morale. Lowell Thomas is shown at the 11:30 mark, keeping the public informed of the latest developments.

Thanks for the tip, Mike! It’s truly amazing to see the amount of effort that went into live radio broadcasts.