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14/11/2012: 4G clearance Freeview retune for North Wales and the Isle of Man

freeview retune
Viewers across North Wales and the Isle of Man will be affected by the latest in a series of Freeview frequency changes on the 14th November, when TV services have to move to clear frequencies for the rollout of 4G mobile internet services, which launch next year.

Consequently, some Freeview services will be off air for a time, and viewers will have to retune, in order to regain missing Freeview channels.

In Wales, the digital multiplex carrying ITV1 Wales and S4C will be changing frequencies at both Moel Y Parc and Llanddona main transmitters. This will affect all viewers using Welsh TV services along the North coast between Holyhead and Queensferry, as these two main transmitters feed all the local relays. Services from the Winter Hill transmitter, including ITV Granada, are not affected on the 14th November.

On the Isle of Man, numerous relays will see frequency changes, but all sites in the island will see some services being interrupted as a result of the changes. The changes here will especially affect the Freeview HD multiplex.

Why are the frequency changes happening?
Part of the frequency band that has been used for TV has now been earmarked for 4G mobile broadband services. In technical terms, services currently being transmitted on UHF channel 61 and 62 are being mostly moved to UHF channels 49 and 50, and services now on 49 and 50 are being moved to 39 and 40. The end result is that everything above UHF channel 60 is vacant for 4G services. UHF channels 63-68 were cleared at digital switchover.

Which transmitter sites are affected by the frequency change?
The full list follows.
Note: BBC-A refers to the digital multiplex carrying BBC One, Two, Three etc; BBC-B is the Freeview HD multiplex, D3&4 is the multiplex that includes ITV and Channel 4 (plus S4C in Wales), Arq B is the commercial multiplex broadcasting Film 4 and VIVA among other services. Where changes to BBC-B are indicated, viewers without Freeview HD are not affected.

Isle of Man
Relay sites:
Douglas   D3&4 moves from ch60 to ch60- (introduction of an offset); 
Beary Peark   BBC-B moves from ch50 to ch40;
Jurby   BBC-B moves from ch50 to ch40;
Laxey   BBC-B moves from ch50 to ch40;
Port St Mary   BBC-B moves from ch50 to ch40;
Ramsey   BBC-A moves from ch49- to ch39;
Union Mills   BBC-B moves from ch50 to ch40.

Main transmitters:
Llanddona   D3&4 moves from ch60 to ch60- (introduction of an offset);  ARQ B moves from ch50 to ch40;  
Moel y Parc   D3&4 moves from ch49+ to ch39+;
Relay sites  
Bethesda   D3&4 moves from ch60 to ch60- (introduction of an offset);  
Bethesda North  power boost from 2W to 4W ERP only;
Cemaes  power boost from 5.6W to 11W ERP only;
Coed Derw   D3&4 moves from ch50 to ch40;  
Glyn Ceiriog   D3&4 moves from ch61 to ch49;  
Glyndyfrdwy   BBC-A moves from ch62- to ch50;  
Llandecwyn   BBC-A moves from ch61 to ch49;  
Llandderfel   BBC-A moves from ch62- to ch50;  
Llanengan   BBC-A moves from ch61 to ch49;  
Llangollen   D3&4 moves from ch61 to ch49;  
Llanuwchllyn   BBC-B moves from ch50 to ch40;  
Maentwrog   D3&4 moves from ch50 to ch40;
Morfa Nefyn  power boost from 14W to 28W only;
Storeton Wales   BBC-B moves from ch60 to ch60-. (introduction of an offset)
Waunfawr  power boost from 5.2. to 10.4W ERP only 

Pop up messages will run on the D3&4 multiplex and shown on ITV1 and Channel 4 in the 7 days leading up to the changes.

When will the changes take place?
Work will commence shortly after midnight on the 14th November 2012.
  • Viewers receiving the full Freeview service from main transmitters will be able to retune by 6am (or thereafter);
  • Viewers on relay transmitters where frequencies are changing will need to wait until later in the day before services are restored (see list above). Most sites will be back on air before 3pm. Port St Mary and Kimmeragh (Isle of Man) plus Maentwrog are expected to be the last three relays to be worked on, with services expected to be back on air by no later than 5pm. Timings are subject to change.
  • Viewers on relay transmitters where frequencies are not changing will see breaks in service as their parent transmitter is being reconfigured - i.e. sites in North Wales and the Isle of Man not listed above.
  • There are no changes to services from the Winter Hill Granada region transmitter, which is widely available across the affected region. Winter Hill changes next spring.

In the above list, what is meant by "introduction of an offset"? 
The central frequency of the multiplex is being moved very slightly to protect other TV services and - in the case of services on UHF channel 60 - to move them a bit further away from UHF channel 61, which will be used for 4G mobile broadband. Most modern receivers will have no trouble with the offset.

Will I be able to get 4G mobile broadband services in North Wales and Isle of Man after the 14th November?
Not immediately. The clearance paves the way for the rollout of 4G services in the "800 MHz" frequency band during 2013.  Further clearance retunes have yet to take place in other regions before the 800 MHz band is free of TV and can be released UK-wide for 4G. Some 4G services are being run in the 1800 MHz band by EE in selected major cities until then.

I've heard 4G will interfere with my signal. What do I need to do on the 14th November?
Initially nothing. The interference is due to the fact that the 4G services will operate close to TV services on the frequency band, although the actual frequencies being used by 4G will be cleared (see above).

Once 4G services on the former TV frequencies commence in your area, then those within 2km of a mobile phone base station will be particularly liable to encounter interference. TV receiving equipment is still designed to receive services in the 800 MHz band, although soon there will be aerials and TVs that are not. However, given the proximity of 4G services to TV services from 2013 onward, it is likely that some householders will need to install filters to block interference. It is currently envisaged that a mitigation company set up by the mobile phone operators who win the forthcoming auction of the 800 MHz band will offer affected householders one filter. Additional filters for additional TVs will not be catered for. Viewers who have satellite will not receive assistance.

Are there any changes to the channel line up on that day?
No, there are no planned changes. Any changes that may happen are purely co-incidental.

Viewers who didn't retune their Freeview receiver on the 19th September and 17th October - when there were some changes to the Freeview channel line up - may notice that some services have moved. (This mostly affects viewers able to receive the full Freeview service.)

Some viewers may need to watch out for unwanted regional duplicates when retuning, where reception from more than one transmitter / region / country is possible.
Is there a list of forthcoming 4G clearance retunes?


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