Pulsed potentiostatic deposition provides a nevi means for the elaboration of multilayers to produce magnetic sensors, Alternate layers of nickel or cobalt of nominal thicknesses from a few angstroms to a few nanometres separated by a copper film have been electrodeposited from a single electrolyte containing a low concentration of copper ions. The thicknesses and deposition rate have been monitored in-situ with a quartz microbalance during the growth of each layer in order to obtain precise information to account for the physical properties of the heterogeneous materials prepared by this process.