There are quite a lot of these stations, broadcasting on different frequencies. Wikipedia has a nice list.
Unfortunately this also means a clock you buy in the US won’t necessarily work elsewhere in the world. This (IMHO) is one of those things should all agree on and use a single standard, but time and timezones are really complex. Some nice initiatives have been created like beat time from swatch but it ended up nowhere.
There are quite a lot of these stations, broadcasting on different frequencies. Wikipedia has a nice list.
Unfortunately this also means a clock you buy in the US won’t necessarily work elsewhere in the world. This (IMHO) is one of those things should all agree on and use a single standard, but time and timezones are really complex. Some nice initiatives have been created like beat time from swatch but it ended up nowhere.