Electrodeposition conditions have been studied in order to prepare Cu/Fe20Ni80 multilayers by the pulse potential method using a single electrolyte. Individual layer thicknesses ranged between 0.5 and 3 nm. Up to 40 bilayers were electrodeposited either on copper or glass plate substrates. Grazing angle x-ray diffraction showed good coherency between the layers. A magnetic coupling between FeNi layers has been observed with a magnetoresistance ratio of 2% at 2 kOe and 77 K.