You see it all the time. A news anchor sitting at a desk somewhere in LA or NY takes us live into the field to talk to a reporter on site somewhere. It could be a few states away or across the globe. But sometimes, there’s this really annoying delay in the feed where the anchor would ask something, we’d cut to the reporter, there’s an uncomfortable 2-5 second delay, then the report replies. Sometimes its so bad that they both talk over each other, not being able to hear the other until a few seconds in, then they both pause because neither one knows who is going to speak next
The absurd thing is, the viewer is getting this live in real time. But if we can see it, why can’t the reporters? Light travels so fast it can circle the globe 7 times in a second, so even if they are bouncing the feed off satellites, the delay should be miniscule. What causes this weird delay and why can’t they fix it?
Apparently the delay for transmitting a signal to a satellite in geosync orbit (where most communication satellites orbit so that they can remain over a particular area,) and back down is approximately one quarter of a second.
there is transmission over cable and satellite. there also is analog and digital processing which take different times. there is even delay with local tv stations and reporters in the field.
on both radio and tv i can have two different stations on the same network tuned in and they don’t happen at the same time.
It’s the amount of processing the signal goes through - the digitizing, compression algorithms, routing, decompressing, etc. It can be really entertaining to line up three TV’s - one tuned to a digital over the cair channel, one tuned to the same channel on cable, and the third tuned to the cable’s analog broacast of the channel, and try to figure out which signal is getting to you first.
Sitting in my satellite truck right now. There is a delay with regards to the uplink / downlink time of about a half second. The biggest delay culprit is the digital encoding / decoding which adds another 2-4 seconds to the process. Multiply by # of satellites used for a signal generated on the other side of the world and you get big delays.
In the old days with analog satellite transmissions the delay wasn’t bad at all. But you could only get two shots in on a transponder, and it was expensive. Now with digital you get 7 signals with a corresponding decrease in cost.
I will be going up on Galaxy 16 Transponder 6 Slot D at 16:45 EST for our 5pm shot.
You may also notice digital delay when using current cell phones vrs the older analog style.
It’s also that the reporter in the field is often waiting for the camera operator to give him a signal to begin. He can’t be sure if the question he hears in his earphone is on the air or not.