So many times I see a guy video calling another crew across the country and it can take a solid 5-10 seconds before we hear them reply. I’ve seen kids in siberia with better ping.
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This is a great question and there’s actually a lot more to it than most people would realise!
It all depends on how your connecting your two “locations” and understanding that broadcast has to be 100% reliable.
If we use normal public internet, there’s a lot of unknowns… And the things that affect our teams/FaceTime/etc can affect the TV call too. But the difference is rather than one person breaking up or stuttering to a few others on the call, that break up is on TV being watched by potentially millions!
So in many cases we try and work around that. The most common is by using satellites! Where your rent a frequency for the duration of your broadcast (that you and only you are meant to use) and connect to a satellite and receive it back at the studio. This means you always have a fixed amount of data with a fixed route back with a dedicated reliable connection!
The downside of satellites is that the amount of data you can send is really low for the cost… So you have to “compress” your video and audio. I could talk for hours about compression, but the key fact is that the most efficient forms of compression work by taking a whole image from your video once every second (sometime more often or less often) and for all the frames in between only transmit what’s changed since the full one.
For example if your video is a ball bouncing, you don’t need to send the whole ball every frame, you can just say, repeat the last frame and move this section of it down a bit (this is a big simplification, but close enough)
The problem with this is you need the whole second at EACH to start getting any video. Which means it will take at least 2 seconds, not including the time it takes for the data to be sent to a satellite truck, sent up to space, processed and send back down to a receiver…
In the last few years we’ve actually got much better at using the normal public internet and writing clever code to deal with dodgy connections and we are using the internet more and more for TV. It’s also possible to get your own dedicated connection put in between your locations. Many big studios and production centres have links to ISPs that are dedicated for broadcast use. For example in the UK every footballs stadium in the country has dedicated fibre run back to a hub in Milton Keynes with network hardware at every single one. So company’s like sky/BT/ITV can produce their football coverage without using satellites!
Source: Broadcast network engineer, work on things like premiere league football, Wimbledon, Olympics and more
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