In-game betting: how can I figure out the delay on my TV?

We've all been in bars where tv's are seconds off

Recently our neighbors went nuts for a goal 90 seconds after we saw it.. I guess they could have gone back on the recording at some time?

Is there a way to calibrate your TV (figure out the delay) without having a friend at the game?

Thx in advance :)

 All providers have some sort of delay, some worse than others. The only real way to gauge it (other than friend at game) would be to compare it to a radio call of the same game, providing the radio broadcast wasn't using the 7 second delay. I used to do that while watching Huskies games so I could hear the Bob Rondeau call instead of the meatheads on TV. Most of the time I could pause my dvr to match it up with the radio delay. Other times I couldn't when radio was real time.