Broadcasttelevisionreceptionusestheradiospectrum.InthedaysbeforedigitalTV,spots,hash,snowstorms,colourandvisiondistortionandoccasionallycompletelossofpicturewereallsymptomsofthesamecause–electromagneticinterference.Interferencestilloccurs,butitsmanifestationondigitalpicturesisdifferent–