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FAQ: Freeview frequency changes and retunes

Millions of households will need to retune Freeview in order to keep receiving channels in the coming months. But why and will it affect reception?

Alex Tyler has been finding out for a516digital:

Between now and May 2020, a chunk of the airwaves currently used by Freeview will cleared so that they can be used for new "5G" mobile broadband services. This is called the 700MHz frequency band.

As a result some Freeview channels will need to move to new frequencies and viewers will need to retune to continue watching. Importantly, the changes also affect YouView (BT TV, TalkTalk TV, Plusnet TV), EE TV and Now TV Smart Box users, as all of these services piggyback off Freeview.

Viewers in most parts of London, the Midlands, North West England and the South East will be affected during February and March 2018. Other parts of the UK will follow, although northern Scotland has already completed the process - albeit affecting far fewer viewers.

When do I have to retune?
Retune dates will be released ahead of each frequency change by Digital UK, the organisation that was previously responsible for digital switchover.
Details of the areas affected in early 2018 can be found here.

Will additional support and information be available?
Freeview will have a dedicated area on its website explaining the changes and an advice line will also offer assistance on retuning. These will go live closer to the time.

Will all channels be affected?
In most areas no. In many cases only certain groups of channels will be affected.

However, in the run up to the changes, engineering work at transmitter sites may result in spells of weak or degraded reception, or no reception at all.

The BBC's interactive transmitter checker carries details of any work that might have affected your reception of BBC services. Unfortunately there isn't a similar public  tool for commercial channels.

Which channels are most likely to be affected?
Commercial, HD and local TV channels are the most likely to be affected depending in your local Freeview transmitter: for example in London, the frequency changes will affect services including BBC News HD, FreeSports and London Live, whereas the main five channels won't be affected at all.

Viewers in parts of the East Midlands will see services such as 5Spike, Yesterday and Ideal World affected, alongside FreeSports and QVC HD.

Will I lose channels?
Freeview channels are grouped into multiplexes. The main six national multiplexes that carry all of the main channels will retain the same or similar coverage area, so that viewers should continue receiving the main Freeview service. An aerial change might be required.

In addition, there are two temporary multiplexes of channels carrying HD services like 4seven HD and BT Showcase HD and one local TV multiplex that have reduced UK coverage. A small number of households may lose coverage, especially those that are currently technically outside a service's core area but still receive signals. The same is true for those households that can currently receive services via overspill reception from another TV region.

To reduce the impact on core coverage, there will be some additional changes at some transmitters: for example, Brighton's Whitehawk Hill transmitter is already simulcasting some channels on two frequencies in the interim. The Rouncefall transmitter in Essex and Haslemere relay in Sussex will start transmitting extra channels to help reception from next year. Local TV services in Manchester, Liverpool and Blackpool/Preston will benefit from a power boost.

Will I need a new aerial?
In some areas, a wideband "Group K" aerial might be required as services move to frequencies not previously used in an area.

If you lose access to the main Freeview channels like BBC One or Channel 4 as a direct result of the frequency change, then you might be entitled to support and a free aerial upgrade (not indoor aerials). Details will be provided around each retune event regarding what to do if reception is lost. A pilot exercise in the Scottish Borders in March 2017 confirmed that relatively few households needed any remedial work on their TV aerial.

Will I need a new receiver (TV or box)?
No. Although if you do want or need to buy a Freeview TV or receiver, make sure it supports Freeview HD or Freeview Play so that it's future proof.

Do I only need to retune once?
Sadly, in some areas it will be necessary for multiple frequency changes and thus retunes to take place during the next 2 1/2 years. This is so that interference can be minimised. If you're affected, more information will be provided ahead of each retune day.

I have a TV that retunes itself. Do I need to retune?
While many TVs are now able to automatically add, move and delete channels, a frequency change will require a retune.

What about 4G interference to Freeview?
In a separate process to the aforementioned frequency changes, 4G mobile services in the adjacent 800MHz band will continue to expand coverage. So you may need a 4G filter, which blocks out interference if you haven't already. However for many households, the new Freeview frequency changes will move services further away from 4G.

How does this 700MHz clearance work from a technical point of view?
The number of Freeview channels varies depending on location and transmitter used. The fewers channels that are available in an area, the fewer frequencies are used.

In areas where there are fewer Freeview services, the 700MHz band should be cleared during the initial retune. In areas where there are more Freeview services available, then some services currently in the 700MHz band will move to new frequencies, while low powered temporary multiplexes move the other way into the 700MHz band. In some areas, this process will take place over 2 1/2 years.

At the end of the process, the temporary multiplexes will be turned off, and the 700MHz band will be clear for future 5G services.

What will happen to channels on the temporary multiplexes at the end of clearance?
Changes will be made to the core Freeview service to accommodate displaced channels.  At this point, older Freeview boxes may cease to receive all the channels that they could previously - but this won't happen for some years yet.