Reports that current atmospheric conditions may lead to Freeview TV reception problems for millions should be taken with a rather large pinch of salt.
High pressure conditions, such as those persisting over the last month across the British Isles can lead to problems receiving Freeview.
During such weather conditions, tropospheric ducting can cause signals from more distant transmitters to interfere with local services. The BBC has a guide explaining the science behind it.
As a viewer, you might expect picture break-up or temporary loss of signal on some channels as a result of the conditions. A nuisance that will clear when weather conditions change.
But how many viewers will this affect?
If you live near the coast, it’s more likely to be a problem. The tropospheric forecast for the next few days indicates the east coast above The Wash up to Scotland will see the ideal conditions most likely to cause the reception issue. However, given the location, it’s unlikely to affect millions of viewers.
However reception issues in North Yorkshire, Teesside and Durham Coast may actually be caused by engineering work on the transmitter at Bilsdale, as more services are migrated across to the new 300 metre mast.
Viewers in the south east can be affected even when there’s just a slight suggestion of tropospheric ducting. That’s because a decade of frequency clearances to make way for 4G and 5G services have left too few clear frequencies for broadcasters to use that won’t be subject to co-channel interference.
The situation is worst in the south east because the airwaves need to carry up to six national UK Freeview multiplexes, plus numerous French multiplexes, not just once, but on a different set of frequencies for each transmitter in the area. And there’s occasional interference from the Netherlands.
Here, broadcast engineers have provided a number of extra relays to help viewers access a more reliable, stronger signal. But the relays don’t all offer the full selection of channels. And during the worst conditions, interference may affect them as well.
Households who encounter frequent issues with reception may have already moved across to another TV platform, such as Freesat, effectively immunising themselves against future weather-related Freeview interference.
Again though, while the interference can affect many households, it would rarely affect millions.
In fact it’s high pressure weather conditions in the winter that can generate the most complaints regarding Freeview reception. Foggy weather creating a temperature inversion can really affect early evening and prime-time TV, as well as again at breakfast time. During these times, reception issues may indeed skyrocket with social media awash with complaints from viewers.
Normally, the clearest of frequencies in any given location are reserved for the main public service channels such as the BBC, ITV and Channel 4. That doesn’t mean they won’t have interference, but it’s less likely except in the severest of cases or where an aerial installation is insufficient.
Commercial multiplexes, carrying channels such as Quest, Talking Pictures and Food Network use frequencies more likely to be affected by interference. However these channels are normally watched by far fewer viewers, reducing the overall impact.
So will millions face Freeview outages this week? No. Just like last week and the week beforehand when these headlines were circulating, many viewers won’t notice a thing.
Acknowledgements
PICTURED: Bilsdale transmitter. COPYRIGHT: Arqiva.