Some magnetic properties and the planar Hall effect are investigated in NiFe-Cr and NiFe-Mn magnetic double layer films, prepared by vacuum evaporation. The appearance of a unidirectional anisotropy is observed after annealing in a magnetic field. The exchange field He characterizing this kind of anisotropy is measured by Kerr effect technique and is estimated from the planar Hall effect curves. The experimental plots of Hall effect are compared with a theoretical solution derived from the Stoner-Wohlfarth model ferro-antiferromagnetic double layer films.