Nondestructive Sensing of Magnetic Cores

Abstract

A "Nondestructive" method for sensing the information state of magnetic-memory cores is under development. This new method involves the use of a quadrature magnetic field which, when pulsed, produces an output voltage. The polarity of the output voltage contains the information—a positive output pulse represents a ONE, and a negative pulse a ZERO. Reading in this manner can be repeated indefinately without destroying the information held by the core. The method has proven to be exceedingly fast, giving output pulses of 0.2 microseconds in duration, and because of the rapid flux change when sensing, the output voltage has been observed as high as two volts per turn.