No, it's going from an internal location to an outside location and is a piece of cable with a connector on either end. The internal end will likely be presented next to the aerial amp to which it is connected. To use a signal from the power pillar just disconnect the external cable from the aerial amp and disconnect the cable on the aerial amp that feeds the TV socket inside the van. Connect them together. Plug in your TV in the 'normal' way.
Outside make up a piece of cable - usually about 25m - with the appropriate plugs on either end so that it will plug into the pillar and to the caravan. Plug in, retune your TV and all should work. Note that there may be frequency changes on the site system such that the incoming signal from the pillar may not be on the same channels as you have received off air.
You can buy the necessary connectors and cable from Toolstation or Screwfix considerably cheaper than from a DIY shed. The 'standard' TV connector shown in #11 are known as F-type, that in #13/2 are called Belling-Lee (for which this needs plug to mate with.)