ITV1+1, ITV1HD, BBC One HD regional services on Freeview
For cost-saving reasons, both the BBC and ITV do not currently provide full regional services on certain channels.
ITV only provide four regions for ITV 1 HD: London, Granada, Central West and Meridian Southampton, plus STV West HD is provided by STV in Scotland.
Viewing ITV 1 HD outside these regions, the closest region to this list is provided.
In addition, ITV 1 +1 is also limited to the above regions, with the addition of Yorkshire and ITV Wales. Again, you may find you have a different region on Freeview 33 for ITV 1 +1 than for Freeview 3, ITV 1.
On Freesat, or fSfS without a card, Yorkshire and ITV Wales are not on ITV1+1, and an alternative region is provided.
These regions are now clearly indicated on the site:
The BBC currently provides, on Freesat HD and Freeview HD a single national BBC One HD service that has no regional news and no opt-outs in Scotland, Wales and Northern Ireland.
9:32 AM
Briantist
Sorry forgot to thank you for the link - 17 July.
I am still trying to digest the info there.
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John Fisher: No problem. Basically, there is no link between the signal "quality" and the picture quality, unlike with analogue.
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1:37 PM
John Fisher:
Signal *strength* is the raw level of power coming in on the selected UHF channel, from *all* sources - the transmitter you want, other transmitters using the channel, signal distortion and noise.
Signal *quality* is a measure of how much interference or distortion there is. Any of either causes the box to read the wrong value for the carrier. The signal is encoded in a way that allows the box to determine the most likely value, but this decision can be wrong if the levels of interference, noise, or distortion are too high. To combat this, the signal carries redundant information to help guide the decision and correct the errors (called 'forward error correction', FEC). Signal quality is usually an indicator of how many errors were corrected.
Unfortunately on most boxes, both measures are useless for diagnostics. The 'strength' is usually a percentage relative to the maximum possible input from one multiplex alone with no interference, but as this differs from box to box, 50% (say) on one box may mean something different from 50% on another box. As a general rule you should stay well below 100%, as the combined power from all multiplexes (and remaining analogue channels) from all receivable transmitters would exceed the power on that one single test multiplex. The upper limit recommended by the Confederation of Aerial Installers for one multiplex (before switchover), which allows for a combination of five high-power analogue and six low-power digital signals, falls at about 50% on my box (Humax PVR-9200T). Some boxes apparently under-read if the signals are actually over the maximum they can handle.
Signal quality on many boxes (again, including mine) is simply 100% minus the relative number of uncorrectable errors over the last few seconds. It doesn't tell you how many errors were corrected, which means you can't find out how close to the point of break-up you are, and you can tell visually and audibly if it isn't capable of correcting all the errors, as it usually starts breaking up or giving audible 'pop' sounds at this point.
If the number of uncorrectable errors is low, you can get a more blocky or blurry picture without actual tearing (where a whole line is discarded). This is right at the top of the so-called 'cliff edge'. Otherwise, if the signal quality is good enough - sufficient signal, low enough noise and interference - all errors can be corrected and the decoding is perfect. Digital can tolerate up to about 20dB, or 100 times, more interference/noise than would start to cause problems on analogue, though the problems would be very minor at this point. However, you could still get an understandable picture and sound on analogue with noise levels greater than will cause complete failure on digital.
Note that you can still get a blocky or blurry picture with perfect reception, if the broadcaster is compressing the picture too much. We can only cram nine channels into the space that used to carry one by throwing a lot of information away. It's designed to throw away the least-noticeable information, and only transmit the changes between pictures, but if too much information is discarded you can see the joins between coding blocks, distinct colours where it should be smooth, or blurry detail that should be sharp. There's nothing at all you can do about this - the information was never transmitted, it wasn't lost in transit.
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4:23 PM
How long do you think we will have to wait til we get a local HD BBC 1.I'm getting fed up with keep changing from channel 50 to 1 while I'm watching Breakfast and Points West and then back again.
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dorix: There are no current (2011/12) plans to provide local news in England on BBC One HD.
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9:05 PM
THanks Mike Dimmick for the detailed explanation.
On my Belmont channels I have 9 or 10 for quality but on the HD channels I am getting from Sandy Heath it is only 4 but the pictures looked as good as the Belmont ones hence my query.
Another thing has cropped up today is that the onscreen messages to remind of the rescan for Aug 3 and 17 were showing Aug 10 and 24.
Anyone any idea what is going on.
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4:18 PM
THe onscreen message dates for the rescans are back to the correct dates today.
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John Fisher: I'm very pleased to hear they fixed the messages.
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5:35 PM
Cambridge
Hi
I am using a Humax HDR T2 Freeview box on Tacolneston. Generally great way to get HD, but have noticed that ITV1 HD seems to be the only channel with a lip sync error. The picture is often so far ahead to make me revert to SD. The Humax adjustment only makes th3e error worse. Any thoughts?
Tim
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TimD's: mapT's Freeview map terrainT's terrain plot wavesT's frequency data T's Freeview Detailed Coverage