Drag Arms ( bingo )



The drag arms are a couple of metal bars leaning up against cams on the front of the control unit. They periodically stop a couple of the cams from rotating briefly, and in the process alter the positions of the cam lobes between themselves and the rest of the control unit. The net affect is to randomize the timing of certain events during the cycling of the game, such as the amount of time the spotting wipers turn.