Yesterday, we showed an ad for WCCO radio that was published in Broadcasting magazine in 1943, and we asked readers to spot the typo, and here it is. The New York network copy writers included the wrong frequency. WCCO was at that time (and still is) on 830 kHz. But the ad shows the frequency as 780 kHz, which was (and is) the frequency of the CBS Chicago clear channel station, WBBM.

The Minneapolis station had been on 810 kHz until 1941, when the dial was shuffled by NARBA.  It’s been on 830 since March 20, 1941.