Television Delay on Cable?

Raistlin · 11-03-2005, 23:39

I'm currently "enjoying" the RND festivities curtesy of my Cable Connection (Samsung STB).

Thanks to the wonderful construction values of the flat that I live in I can also hear my neighbours TV and they are also watching RND.

I'm starting to get a headache 'cause my neighbour's TV is about 8 seconds or so ahead of my TV.

Any way I can get this sorted or is this a "known issue"?

punky · 11-03-2005, 23:41

Known issue. They are watching it on terrestial, and you on cable. Because the cable BBC1 runs off the original terrestial, there is lag.

I can watch BBC1 on terrestial, and then if I miss a word, flick over to the BBC1 cable and hear it again

Stuart · 11-03-2005, 23:45

There is normally a several second delay on live television caused by the time taken to encode it. There is a similar delay on Freeview. It's part of the encoding process, nothing you or NTL can do to reduce it.

Tommy Rattler · 11-03-2005, 23:53

Eight seconds does seem a bit extreme. Two or Three seconds is the normal time lag in my experience to date! And there's nowt that can be done to improve this as explained above.

Raistlin · 11-03-2005, 23:54

On the subject of RND.....

Yummy Yummy, she's a honey!!!

jtwn · 12-03-2005, 00:45

If i remember, one time i could that it was either between the itv regions or the bbc regions the delay was enough for after the delayed remote response, switching of channel there was still a second before what was on the other was repeated.

Maybe try viewing different BBC region/country channel.

ian@huth · 12-03-2005, 01:09

When we had NTL DTV in the study and Sky in the lounge I could be watching a program in the study, walk downstairs and not miss a second of the programme if the wife had the same channel on downstairs. Why the difference between the two digital platforms?

Tommy Rattler · 12-03-2005, 01:17

Quote:

Originally Posted by Raistlin

On the subject of RND.....

Yummy Yummy, she's a honey!!!

Whilst your observation is probably true

- I guess your original query concerning delay between terrestrial and cable transmissions is no longer a concern?

Ignition · 12-03-2005, 10:21

The delay is caused because of a few things. Obviously the delay over satellite which ntl are also subsceptible to, the processing latency at headends, the latency over the fibre network serving the individual hubsites, the buffering that's done to provide resiliency in the case of an SDH 'hit'.

Biggies really are the multiplexing that is done at headends, with the buffering, etc, that is required there (headends don't pump the stuff out straight away there's a slight delay while various processes are done to it), and satellite round trip times.

You'll also find delay varies upon the channel as well, Freeview will arrive first on some channels, Sky on others.

Tommy Rattler · 12-03-2005, 10:28

Now you've got me interested too!

Thanks for the explanation.

One bit that flew over my head..... "an SDH hit"?

Sorry - am still a noobie to this!

Ignition · 12-03-2005, 10:36

SDH hit = when an SDH network reroutes traffic for whatever reason, causes a slight delay in transmission.

Raistlin · 12-03-2005, 15:40

Quote:

Originally Posted by Tommy Rattler

Whilst your observation is probably true

- I guess your original query concerning delay between terrestrial and cable transmissions is no longer a concern?

It was bothering me for a while but then the Miss World lady came on the screen and I sort of got distracted, sorry.....

Tristan · 12-03-2005, 16:28

Quote:

Originally Posted by ian@huth

When we had NTL DTV in the study and Sky in the lounge I could be watching a program in the study, walk downstairs and not miss a second of the programme if the wife had the same channel on downstairs. Why the difference between the two digital platforms?

NTL get the channels from three places. Most are taken off satellite, some are taken from digital terrestrial, and some come over fibre direct from the broadcasters.

In the latter two cases, NTL's pictures will be slightly ahead, as the signal doesn't have to make the 36,000 mile round-trip into space.

Regular analogue terrestrial will be a few seconds ahead of all of them though, for the reasons outlined by Ignition.

KenK · 12-03-2005, 21:27

Apparently, the same effect happens on DAB digital radio. It makes BBC radio's time-check "pips" completely redundant....

Mike Harrison · 12-03-2005, 23:12

There is also a delay for the STB to decode the signal - if you unplug the feed, the programme will run for a second or so after unplugging.