How long is the broadcast delay?

Question

First of all, I am NOT complaining about NBC's live coverage of the Olympics. I live in the eastern time zone so I'm watching it about as live as I can without actually being in Beijing.

But that kerfuffle on the front page made me think of a question I had earlier... how long is the delay for a live event on the other side of the world?

A few days ago I saw a screen behind an athlete, and there was just a bit of a delay between the athlete on the floor and how she appeared on the screen behind her in Beijing.

So, if there's a bit of a delay to get it through the cameras and onto the screen about forty feet away, how long does it take to get up to the satellites and down through our television sets?

Answer 1

The exact delay would have to be measured and it depends on a lot of factors like what type of equipment the signal passes through and what route it takes to your TV.  However, there are a few rules of thumb.

The delay through digital encoding / processing equipment is usually between 1.5 and 3 seconds.  That accounts for the delay you saw on the local monitors.

The delay on a satellite hop (transmitting to the satellite and receiving it on the other end) is usually about 2 seconds.

Therefore, assuming:   encoding at the event + one satellite hop from Beijing to NY + some processing in NY + one satellite hop from NBC to the affiliates + encoding at the affiliate stations for Over The Air transmission, I would estimate 3+2+1+2+3 = 11 seconds.  So I would say about 10 to 15 seconds.  Add another 3 seconds or so for digital cable or home satellite.

I'll ask some of the NY transmission guys tomorrow if they have an exact figure for the Beijing to Affiliate path.

I hope this helps.  Please return and select a Best Answer from all of those submitted.

EDIT:  Network tells me that both NBC and Telemundo have a 5 to 6 second delay from Beijing.  Add approximately 2 seconds for OTA encoding at the station and we are at 8 seconds.  Probably about 9 - 11 seconds for digital cable or home satellite delivery.