About the BBC Blog

This fantastic picture (courtesy of SES) shows satellite Astra 1N during testing. As you may recall, we moved many of our services on satellite over to Astra 1N earlier this year. I thought I'd share it with you as I have some news to tell you about a forthcoming change to the transponder on Astra 1N that carries BBC One HD and BBC HD.

During the summer last year we made a significant change to our HD transponder, upgrading the transmission mode of the BBC's signal from "DVB-S" to "DVB-S2".

This change meant that we were able to make more efficient use of the valuable satellite capacity available on our HD transponder. It gave us the ability to broadcast at 1920 resolution and conduct 3D trials on satellite for Wimbledon, Strictly Come Dancing, Street Dance, the London 2012 Olympic Games and, most recently, Planet Dinosaur.

Over the last year, we have worked closely with our colleagues at Sky, Freesat and SES to investigate how we can continue to make the most efficient use of our satellite capacity in light of improving technology. As a result, we are now able to make a further modification to the DVB-S2 operating parameters which enables us to access additional capacity. This will support the forthcoming launch of BBC One HD for Scotland, Wales and Northern Ireland.

We will be making this change during the early hours of 27 September 2012 and will update our reception advice page which details all our satellite tuning details at that time.

The change will mean different things to different people:

• If you watch TV using Freeview or Virgin Media, or can't currently view HD channels you will not be affected.
• If you have Sky, you should not notice the change and shouldn't have to do anything on or after 27 September. If you do have an issue receiving the BBC HD channels from this date you can try unplugging your Sky set top box, waiting 30s and plugging it back in again. If that doesn't resolve your problem it's best to contact Sky on 08442 411 653.
• If you have Freesat you may need to put your HD box or TV into standby for 30 seconds and then switch it back on again to continue to receive the two BBC HD channels; if the channels are still unavailable then carry out a 'Freesat channel retune'. During last year's changes we found that a small number of devices didn't store the information after a Freesat retune so if that happens try a 'first time installation' or 'full factory reset'. Full instructions can be found in the manual for your digital TV or box. Further help with retuning can be found at www.freesat.co.uk or by calling their customer support team on 08450 990 990.
• If you have any other kind of satellite receiver that can currently receive the BBC HD channels then you should use the new parameters below to tune manually into the services. The current and new parameters for Astra 1N tp.50 are:

We have also contacted satellite and aerial installer trade associations - dthe CAI and the RDI - providing them with information with which to brief their members in case anyone experiencing a problem contacts an installer rather than their platform operator. We will also be putting information about this change on the satellite BBC Red Button page 998 a bit nearer the time because we know not everyone has access to the internet.

If you watch our HD services on satellite, I hope this change won't cause you any worry.

Alix Pryde is Director, BBC Distribution

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