a magazine assembly containing numerous media units is disposed adjacent to a picker assembly . one of the two assemblies is normally stationary , while the other assembly is a traveling assembly . in either case , the two assemblies cooperate with one another to selectively provide the picker assembly with access to the media units that are stored in the magazine assembly . a motion reversal assembly is coupled to the normally stationary assembly and is engageable by the traveling assembly when it enters an end portion of its excursion path . when the motion reversal assembly is so engaged , it moves the normally stationary assembly in the direction opposite to that of the traveling assembly &# 39 ; s movement . the effect is an apparent increase in the traveling assembly &# 39 ; s available excursion length , which makes it possible for the picker assembly to access media slots that would otherwise be disposed in the dead spaces located on either end of the traveling assembly &# 39 ; s excursion path .