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Transmission delay

odds

Standard Member
I was having a conversation over the phone tonight with a mate about the golf, he has Cable TV, I have Sky HD and was viewing it on BBC HD. There was a 4 second delay in my transmission compared to his, which was really annoying, as someone was taking a putt on my TV he would tell me he had got it or missed it
I even heard the commentary difference over the phone. So how does this happen ?

Pete.
 

Starburst

Distinguished Member
Different signal paths from the source to your home any of which can add a delay compared to another then delays inherent in using a more power hungry HD codec and delays introduced decoding that HD broadcast and then perhaps a delay creating an image on a HD display compared to a CRT and audio sync delay to match everything up.

From what I have read the BBC make an effort to sync up all their broadcasts but once it's left the BBC there are external factors which account for delays when viewed in different homes with different equipment from basic analogue tv and radio to DAB and DTT then cable/satellite and of course the internet.
 

TaylorMUK

Active Member
I've noticed this on all HD channels. Try watching Sky Sports 1 and then changing to Sky Sports HD1 - you'll see and hear the last second or so repeated !
 

simon194

Well-known Member
I was having a conversation over the phone tonight with a mate about the golf, he has Cable TV, I have Sky HD and was viewing it on BBC HD. There was a 4 second delay in my transmission compared to his, which was really annoying, as someone was taking a putt on my TV he would tell me he had got it or missed it
I even heard the commentary difference over the phone. So how does this happen ?

Pete.

The bulk of the time is taken up with compressing, multiplexing and encrypting (where necessary) the broadcasts prior to uplinking, then the receiver has to decrypt, demux and uncompress the signal.

I've ignored the 52400+ miles that a satellite signal has to travel because that only accounts for around 0.2secs of the total time.
 

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