yes, I remember the WWV time signals. The reason that the town’s ended about 20 seconds before the top of the minute was so the stion could put in their time announcements. WWV had their time announcement at 53 and a half seconds before the top of the minute. But their sister station in Hawaii, WWVH, did theirs first at 46 seconds to the minute. on days and nights when you get really good short wave propagation, you can hear both stations make their time announcements. WWVH uses a female voice and WWV uses a male voice. That’s how you tell them apart. Also at the minute before the top of the hour, WWVH does their station identification, and at the top of the hour WWV does theirs.
Then there was CHU in Canada, that would alternate the announcements between English and French.