BBC HD to switch to DVB-S2 on 6th June 2011
The high definition (HD) television channels on satellite require a lot more bandwidth (number of bits per second) than the standard definition (SD) ones, as you might expect.
However the additional capacity required is reduced in two ways. First the MPEG-4 compression system is used (rather than MPEG-2) and generally the DVB-S2 modulation system increases the bandwidth of each satellite transponder.
Generally speaking, around nine SD television channels can be carried on a transponder in DVB-S mode, and four HD channels on one in DVB-S2 mode.
For historical reasons, the BBC's Astra 2D transponder 50 has been providing BBC One HD and BBC HD (and also ITV1 HD Merdian South) in the DVB-S mode, and this has used all the capacity on the transponder, because of the lower bitrate.
The changes
One 6th June 2011, the BBC will switch the transponder to DVB-S2. If you watch using Sky+HD, Virgin Media or Freeview HD you will not have to do anything.If you use a branded Freesat box (or TV set), you may need to put it into stand-by mode for 30 seconds on 6th June. If that doesn't work, perform a 'first time installation'.
Update: Some Panasonic Freesat boxes are unable to deal with the change - see comments below
If you are using a unbranded Freesat box, you may find that you also have to do a 'first time installation' to get the channels back.
Some older satellite equipment will not support DVB-S2. If you can't watch Channel 4 HD, then you will no longer be able to watch the BBC HD channels.
Sky HD, Freesat HD EPG issues
Currently BBC One HD cannot automatically replace BBC One in the Sky EPG at position 101, because there are 15 regional versions of BBC One, and only a single BBC One HD 'stream' on the satellite.BBC Two carries four regions for England, Scotland, Wales and Northern Ireland. For a BBC TWO HD to appear in the Sky EPG at position 102, the BBC would need to provide four versions of BBC TWO HD.
All the other BBC channels are national, and have no regional components. BBC Three timeshares with CBBC, BBC FOUR timeshares with CBeebies, plus there is BBC News, BBC Parliament and BBC Alba.
The extra capacity found by moving to DVB-S2 could allow the BBC to provide BBC Three, BBC Four, CBeebies and CBBC channel in HD, and these could be provided in the "usual" EPG slots for Sky HD and Freesat HD users, which would put them on the lower numbered channels nearer the top of the guide.
9:07 PM
Brian you confused me now, isn't T terrestrial and we are talking satellite S ?
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11:21 PM
According to the BBC HD EPG, between 2.00am and 3.00am it shows programmes start at 3.00am. Will this be the hour when the switch over takes place.
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7:50 AM
Freesat 108 and 109 "No Signal"
when do we expect transmission to restart?
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8:45 AM
David: If you have a Freesat receiver then the problem is with the Symbol Rate of 23000 (23.0) that the BBC have chosen for this transponder. I am getting the same "No Signal" with a Panasonic Freesat receiver that you are. BUT! my none Freesat receiver, a Fortec Star Innovation, gets BBC HD and BBC One HD with no problem. What the BBC need to do is to put the Symbol Rate back to 22000 (22.0). The BBC, one of the founders of Freesat, have now created a situation where some Freesat receivers cannot show BBC HD and BBC One HD. How clever is that. If I now want to watch BBC HD or BBC One HD I have to use a none Freesat receiver.
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9:24 AM
Well - I lost BBC One HD and BBC HD on my DVB-S PC this morning as promised by the BBC. The good news is I did a rescan with DVB Viewer and both ITV HD services are (currently) still there and I also found NHK World HD so these are still on DVB-S.
Now to decide how (and if to bother) to try and get access to the BBC HD channels again.
I hope those with 3D sets appreciate the capacity being freed up by switching to DVB-S2 for the (alleged) BBC Wimbledon 3D experiment.
Perhaps the BBC will now switch the rest of their SD tranmissions to DVB-S2 to make further capacity savings...
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9:25 AM
Yes mine is a Panasonic Freesat TV set.
Have done rescans they do not help.
Does it mean Freesat have to send some update out?
Or Panasonic to do a s/w update?
CH4 HD is ok.
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9:30 AM
BBC reception advise have responded "...We cannot answer every query or technical problem,..."
Or to ring "..at www.digitaluk.co.uk or by calling 08456 50 50 50." they have no one able to take calls the machine said.
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9:43 AM
Freesat say it is Panasonics problem.
So I'm in same boat as the i-player with Panasonic Freesat Tv set.
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10:00 AM
David: I have also been on the phone to Freesat and they said the same thing to me, that it is Panasonics problem. The cause of this problem is the result of someone at BBC deciding to have a Symbol Rate of 23000 (23.0). Why didn't they opt for a Symbol Rate of 29500 (29.5) that Sky use for their HD transmissions, then as far as my Panasonic Freesat receiver is concerned, there wouldn't have been a problem.
There are three main Symbol Rates on the Astra 2 and Eurobird 1 satellites,
22000 (22.0)
27500 (27.5)
29500 (29.5)
that could have been used without causing a problem and the BBC pick 23000 (23.0). Barmey or what?
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