Abstract: To reduce the size of a rectifier structure in a vehicular alternator-rectifier combination, a common carrier plate of essentially half-moon or sickle shape, having two wing portions separated by a central portion (31) retains two support plates (20) of essentially square outline. Groups of positive and negative diodes are located in the vicinity of the corners of the essentially square suppport plates, interconnected by connecting buses extending in chord relation with respect to the common carrier plate (22). Exciter or field diodes (13, 33) are positioned in the central portion, free from the support plates and the positive and negative diodes thereon. Four positive and negative diodes can be provided, in which a fourth diode pair (16) is connected to a star or center terminal of the alternator winding. The common carrier plate is formed with an upstanding rim so that the entire rectifier can be encapsulating in a potting or resin compound.