An apparatus for manufacturing catheter electrode-fPCB assemblies, the apparatus includes a tray, a heat source, and a sleeve molding station. The tray is configured to (i) receive an electrode in a designated first recess in a predefined layout of the recess, wherein the electrode is ring-shaped and (ii) receive a flexible printed circuit board (fPCB) strip in a second recess configured to enable to thread the fPCB strip via the electrode to a predefined position of the strip such that a pad patterned on the fPCB strip is aligned with the electrode. The heat source is configured to apply heat for soldering the pad to an inner surface of the electrode. The sleeve molding station is configured to mold an encapsulating sleeve over the electrode-fPCB assembly, while keeping a proximal end of the strip and at least a portion of the electrode exposed.