NBC News projected Reagan as the winner at 8:15 pm EST (5:15 PST), before voting was finished in the West, based on exit polls. (It was the first time a broadcast network used exit polling to project a winner, and took the other broadcast networks by surprise.) Carter conceded defeat at 9:50 pm EST.
http://en.wikipedia.org/wiki/United_States_presidential_election,_1980
I remember the evening Reagan beat Carter. My husband and I arrived at a friend’s home just after 8pm (EST) to watch the results come in. But it was announced that Reagan won even before we were able to make popcorn.