Nonlinear flux gain in magnetic shift registers

The stable propagation of ones and zeros in magnetic shift registers composed of cores coupled with wire only requires that the interstage flux gain be less than unity for small flux transfers and greater than unity for large flux transfers. In practice, it is found that these circuits may be made bistable even without the use of clipper cores on the coupling loop. Bennion and Crane [1] have attributed this nonlinear gain phenomenon to the inductance of the coupling loop which effectively subtracts a contribution from the flux transferred between stages. This flux is eventually dissipated in the loop resistance. In the present paper an attempt is made to verify this conclusion by experiments and by applying a highly simplified model to the transfer process. It is concluded that, if clipper cores are not used, both resistance and inductance are indeed required in the coupling loop if bistable operation is to be achieved.