NIST radio station WWV, relocated from Greenbelt, Md., began official broadcasts from Fort Collins, Colo., in 1966. Immortalized in this photo, the switch was thrown to initiate transmissions at 5 p.m. Mountain time on Nov. 30, 1966. About 80 guests attended the event and afterwards NIST received more than 8,500 notices from radio amateurs noting receipt of the first-day signal.