Freeview has issued a warning to viewers in the south of England and Wales, as a strong area of high pressure could affect TV signals.
The alert is valid from today, Wednesday 15th June, and may particularly affect viewers in the south-west and south of England. Freeview users along the west coast of Wales could see some temporary disruption.
Freeview is advising viewers not to retune this week, as reception will be restored when the weather changes. Retuning now will only result in having to retune again when signals are back to normal.
Why is this a problem?
The BBC explains that the issues are caused by the re-use of the same frequencies for TV services by various transmitters.
It advises that “there will be occasions when certain weather conditions allow the signals carrying television services to travel further than expected. Therefore at these times, you can then receive different television services that are using the same frequency. Normally, the signals from each transmitter can only be received by those homes that have aerials with a direct line-of-sight to the transmitter. Being able to receive more than one signal using the same frequency can cause problems such as pixelation.”
In recent years, the number of frequencies available for use by broadcasters has been reduced. Many former terrestrial TV frequencies are now used by 4G and 5G mobile services. At the end of this month, another TV frequency will be discontinued in favour of 5G.
As a consequence, the remaining frequencies have to be more intensely used. This leads to an increased chance of interference during times of high pressure weather conditions. TV aerial installers in the south of England frequently report interference from French services during high pressure weather conditions. That’s despite the addition of extra relays in the past decade along or close to the south and east coast. Relatively new relays include Ashford (Kent), Clacton (Suffolk) and Rouncefall (Essex).
This week’s heatwave is expected to peak on Friday, with temperatures reaching close to 35°C in the south-east. Temperatures above 30 are widely expected across southern England and south Wales.