The sky / freesat satellite channels are aimed solely for the British and Irish markets. The satellite signal is hence aimed towards the British Isles. These satellite signals are broadcast from the same stationary location at 28.2 degrees east. There are four Astra satellites called 2A, 2B, 2C, 2D and one Eutelsat satellite called Eurobird 1.
As you travel in your caravan further away from the UK the signal gets weaker. Even in the UK the signal strength varies. In England and Wales a 40cm (zone1) satellite dish is adequate for a good reception. In Scotland and Ireland a 55cm (zone2) satellite dish is required.
The area that a satellite signal covers on the earth is known as the “Satellites Footprint”. Each different Astra satellite has a slightly different footprint. The BBC, ITV & CH4 all broadcast from the Astra 2D satellite. This satellite signal is much more precisely aimed at the UK compared to the other satellites in orbit, and is the first signal to be lost as you move further away from the UK.
Below is a map of 2 different Astra satellite footprints. It should give you an indication of the size of satellite dish you require to receive a satellite signal as you travel in Europe with your caravan. The maps below are just a guide. If you were camping in Northern Spain with a 65cm satellite dish you would receive most of the TV programmes broadcast at 28.2 degrees except for the Astra 2D channels (BBC, ITV & CH4). An 85cm satellite dish would allow you to receive some TV and radio stations all over most of Europe.