Discussed are the main aspects of operation, physics, design, and application of toroidal cores as nondestructive read-out analog memory elements. The analog memory element and switch are the basic components of the analog memory device of the open-loop type (i.e., without negative feedback). The toroidal core has been shown, both theoretically and experimentally, to exhibit linear read-write characteristics in pulse remagnetization. Diode switches are the most preferable for writing analog information. Analysis of the output and read circuits required to determine the optimal value for the read circuit resistance is given. The complex studies carried out resulted in a simple analog memory device with ± 3 percent error and the write time of 0.3μs. Ways to improve these parameters are described.