To calibrate an positional sensor, a plurality of image locations and image sizes of a tracked object are received as the tracked object is moved through a rich motion path. The printing is done with multiple printhead dies. A series circuit of a current flow restriction element and a switch is connected in parallel with the return current path forming unit. The device also includes an imaging device operably coupled to the radiating portion. Data from the backlight units is similarly routed back to the controller. The damper device includes annular linings for covering the blades and filling the gaps between the blades, the linings being made of elastomer and being held and clamped when mounted on the blades.