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uk.tech.digital-tv (Digital TV - General) (uk.tech.digital-tv) Discussion of all matters technical in origin related to the reception of digital television transmissions, be they via satellite, terrestrial or cable. Advertising is forbidden, with no exceptions. |
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On Sun, 04 Dec 2016 16:21:34 +0000 (GMT), Jim Lesurf
wrote: As I understand it, it is delays due to the processing of the digital signal. Different sets may have different delays, and radio and TV may have even more different delays. FM radio would have given you Big Ben accurately, but nothing digital is likely to have done. Strictly speaking FM uses NICAM for distribution, and NICAM is "digital". It does add a delay, but I doubt you'd notice it. So your "nothing" aims at the wrong target. The cause is the lossy compression schemes employed for 'digital' TV and radio which the systems take some time to process. Not "digital" per se. Presumably the compression for video takes considerably longer than for audio, but the audio part of a television broadcast has to be delayed to match the picture. Audio on its own, i.e. radio, wouldn't need so much so the delay wouldn't be noticeable. I first became aware of how much delay must be in the system on the day of Princess Diana's funeral, when every channel (except 4) was broadcasting the same material, and the difference between the latest and earliest version was about 8 seconds. The only time you can trust is either a radio controlled clock or the internet. Broadcasting used to be an authoritative source for everything but not any more. Rod. |
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On 04/12/2016 18:08, Mark Carver wrote:
On 04/12/2016 17:22, Bill Wright wrote: On 04/12/2016 16:39, Mark Carver wrote: NICAM itself adds a delay of around 14ms. It's near instantaneous then? Yes, 14ms near ! 14ms? That's about two foot innit? I'll never get the hang of this new money. Bill |
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On 04/12/2016 20:41, Roderick Stewart wrote:
Broadcasting used to be an authoritative source for everything but not any more. That's a fallacy. They always spun us a yarn. The difference is we've got the internet now. It the BBC or any of them said water was H2O I'd check on the internet. Bill |
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On 04/12/16 20:41, Roderick Stewart wrote:
On Sun, 04 Dec 2016 16:21:34 +0000 (GMT), Jim Lesurf wrote: As I understand it, it is delays due to the processing of the digital signal. Different sets may have different delays, and radio and TV may have even more different delays. FM radio would have given you Big Ben accurately, but nothing digital is likely to have done. Strictly speaking FM uses NICAM for distribution, and NICAM is "digital". It does add a delay, but I doubt you'd notice it. So your "nothing" aims at the wrong target. The cause is the lossy compression schemes employed for 'digital' TV and radio which the systems take some time to process. Not "digital" per se. Presumably the compression for video takes considerably longer than for audio, but the audio part of a television broadcast has to be delayed to match the picture. Audio on its own, i.e. radio, wouldn't need so much so the delay wouldn't be noticeable. I first became aware of how much delay must be in the system on the day of Princess Diana's funeral, when every channel (except 4) was broadcasting the same material, and the difference between the latest and earliest version was about 8 seconds. The only time you can trust is either a radio controlled clock or the internet. Broadcasting used to be an authoritative source for everything but not any more. Rod. I'm not convinced I trust a radio controlled clock - mine has shown the time as 36:99 (or some symbols for minutes larger than 100), but usually during maintenance and at a time when you might want a wake-up alarm. I don't recall a problem before the change of transmitter location. The German transmitter is far more reliable! -- PeeGee "Nothing should be able to load itself onto a computer without the knowledge or consent of the computer user. Software should also be able to be removed from a computer easily." Peter Cullen, Microsoft Chief Privacy Strategist (Computing 18 Aug 05) |
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![]() "PeeGee" wrote in message o.uk... On 04/12/16 20:41, Roderick Stewart wrote: On Sun, 04 Dec 2016 16:21:34 +0000 (GMT), Jim Lesurf wrote: As I understand it, it is delays due to the processing of the digital signal. Different sets may have different delays, and radio and TV may have even more different delays. FM radio would have given you Big Ben accurately, but nothing digital is likely to have done. Strictly speaking FM uses NICAM for distribution, and NICAM is "digital". It does add a delay, but I doubt you'd notice it. So your "nothing" aims at the wrong target. The cause is the lossy compression schemes employed for 'digital' TV and radio which the systems take some time to process. Not "digital" per se. Presumably the compression for video takes considerably longer than for audio, but the audio part of a television broadcast has to be delayed to match the picture. Audio on its own, i.e. radio, wouldn't need so much so the delay wouldn't be noticeable. I first became aware of how much delay must be in the system on the day of Princess Diana's funeral, when every channel (except 4) was broadcasting the same material, and the difference between the latest and earliest version was about 8 seconds. The only time you can trust is either a radio controlled clock or the internet. Broadcasting used to be an authoritative source for everything but not any more. Rod. I'm not convinced I trust a radio controlled clock - mine has shown the time as 36:99 (or some symbols for minutes larger than 100), but usually during maintenance and at a time when you might want a wake-up alarm. I don't recall a problem before the change of transmitter location. The German transmitter is far more reliable! So long as you remember to fit an offset to the clocks before you sell them in a different time zone that is... http://www.dailymail.co.uk/news/arti...our-ahead.html James |
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On 05/12/2016 12:34, James Heaton wrote:
wrote in message o.uk... I'm not convinced I trust a radio controlled clock - mine has shown the time as 36:99 (or some symbols for minutes larger than 100), but usually during maintenance and at a time when you might want a wake-up alarm. I don't recall a problem before the change of transmitter location. The German transmitter is far more reliable! So long as you remember to fit an offset to the clocks before you sell them in a different time zone that is... http://www.dailymail.co.uk/news/arti...our-ahead.html James My Sister-in-law bought a Lidl clock and it was always an hour fast and there was no option to tell it to use UK time. Lidl offered her the money back if she brought the clock back. I removed the hour hand and replaced it back an hour, and it has been perfect ever since. Having said that, my wife's bedside clock radio usually shows the right time but a few times a year it resets to 4 hours early. It corrects itself the following night. I can only assume that it misreads a transmission occasionally. Jim |
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Indy Jess John wrote:
James Heaton wrote: http://www.dailymail.co.uk/news/arti...our-ahead.html My Sister-in-law bought a Lidl clock and it was always an hour fast and there was no option to tell it to use UK time. Are you absolutely /certain/ of that? The recent one for sale in Lidl had people claiming it couldn't be offset to UK time, when a few seconds RTFM proved it could. |
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![]() "Andy Burns" wrote in message ... Indy Jess John wrote: James Heaton wrote: http://www.dailymail.co.uk/news/arti...our-ahead.html My Sister-in-law bought a Lidl clock and it was always an hour fast and there was no option to tell it to use UK time. Are you absolutely /certain/ of that? The recent one for sale in Lidl had people claiming it couldn't be offset to UK time, when a few seconds RTFM proved it could. The one I referenced was about 12-18 months ago; Lidl offered refunds on them rather than telling people to RTFM so suggests there wasn't a way of doing it. Other than IJJ's innovative method upthread... Probably the more recent one you refer to had an offset feature in response to this... James |
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On 06/12/2016 10:35, Andy Burns wrote:
Indy Jess John wrote: James Heaton wrote: http://www.dailymail.co.uk/news/arti...our-ahead.html My Sister-in-law bought a Lidl clock and it was always an hour fast and there was no option to tell it to use UK time. Are you absolutely /certain/ of that? The recent one for sale in Lidl had people claiming it couldn't be offset to UK time, when a few seconds RTFM proved it could. Yes I am certain. I read the manual and I also read the relevant threads in various forums (which is where I found the instructions on how to get it apart to remove the hands). That particular clock did not have any capability to change the source of the time signal (which probably explains why Lidl was offering customers their money back rather than providing instructions). Jim |
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On Mon, 5 Dec 2016 02:43:19 +0000, Bill Wright
wrote: NICAM itself adds a delay of around 14ms. It's near instantaneous then? Yes, 14ms near ! 14ms? That's about two foot innit? No it's about 14 feet. 1 foot = 1 millisecond for most practical purposes. |
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