From a great blog post by Joe Posnanski about his recent re-viewing of the 1980 Miracle on Ice:
The game was not broadcast live. Well, that’s not exactly right … it was broadcast live on Canadian TV, so a few people up near the border saw it live. But most of the country — almost all of the country, really — saw it on tape delay, in prime time. The game had ended less than an hour before it was broadcast.
Funny, a lot of people still think they saw the game live. But I know that one of my strongest memories — confirmed by the tape — was of Jim McKay saying that it was tape delay and that if even one person did not know the outcome, well, he wasn’t going to be the one to break the news. I have seen polls through the years that suggested most of the people who watched the game on television did not know the outcome. I know that my father and I did not. That shows you how long ago 1980 was in terms of technology. There’s no way you could keep that a secret now.
Very true. It would have been Twittered out the you-know-what.
Joe Posnanski: 10 Things About The Miracle On Ice