The filtered dynamic spectrum of Cygnus A from the LOFAR station in the UK (station UK608: 51.1°N, 1.4°W, 176 m above sea level). The frequency scale is inverted, with lower frequencies at the top of the plot. The normalised intensity is the intensity after the filtering process, with a normalised intensity of 1 being the expected value for an undisturbed ionosphere. Individual features are numbered to distinguish them in further discussion. The horizontal white lines are the channels removed due to RFI contamination.