A spine of an electrode assembly is constructed by simultaneously deploying a plurality of individual bobbins of lead wire radially around the longitudinal axis of a polymeric tube. A free end of lead wire from each bobbin is electrically connected to a respective electrode and the electrodes are sequentially installed from a distal first location on the polymeric tube to a proximal location. Each lead wire may be helically wound around the polymeric tube between the electrode to which the lead wire is electrically connected and a proximally adjacent electrode, such that each lead wire between adjacent pairs of electrodes has an alternating direction of winding.
