The well-known American time-signal station at Fort Collins Colorado, call sign WWV, was congratulated recently by the U S Department of Defence on the occasion of its forthcoming Centenary. WWV and its sister time signal stations have been on-air since May 1920.
A special announcement and notice of a Special-Event ham radio station, WW0WWV, was made during their time signal transmission.
Listen to a recording of that announcement [here].
[Note - the link requires Adobe Flash to be installed on your PC]