BackPacker, that's not the case in the UK. The MSA on the CAA chart is the height of the tallest obstacle, or highest land + 300 feet.
But I'm unsure how theolderflyer comes up with an MSA of 1900 feet. The CAA charts shows 1300 feet for the Isle of Wight (transmitter at 1297 feet amsl), and 1000-1200 to the east and west.