The toroidal shape of a core is preferred since the magnetic path is closed, there are no magnetic poles and thus very little external flux. This allows the cores to be packed closely together without their magnetic fields interacting. The alternating 45-degree positioning used in early core arrays was necessitated by the diagonal sense wires. With the elimination of these diagonal wires, tighter packing was possible.
The toroidal shape of a core is preferred since the magnetic path is closed there are no magnetic poles and thus very little external flux This allows the cores to be packed closely together without their magnetic fields interacting The alternating 45-degree positioning used in early core arrays was necessitated by the diagonal sense wires With the elimination of these diagonal wires tighter packing was possible