Technical Publications by Bell System Authors Other Than in the BellSystem Technical Journal

* A reprint of this article mav he obtained on request to the editor of the B.S.T.J. B.T.L. 461 462 BELL SYSTEM TECHNICAL JOURNAL paper describes and illustrates, with representative examples, various types of common noise induction in order to lead to an understanding of their nature. The paper includes, in addition, a discussion of simple remedies which may be employed for representative cases of noise troubles due to longitudinal induction. Mobile Radio. A. BAILEY. 3 A.I.E.E., Trans., V. 67, pt. 2, pp. 923-931, 1948. Stabilized Permanent Magnets* P. P. CIOFFI. 1 A.I.E.E., Trans., V. 67, pt. 2, pp. 1540-1543, 1948. ABSTRACT--Permanent magnets are stabilized against forces tending to demagnetize them, by partial demagnetization. It is shown that, after such stabilization, the magnet operates at a point on a secondary demagnetization curve. This curve may be treated identically as the major demagnetization curve is treated in ordinary magnet design problems. Formulas are developed for determining secondary demagnetization curves from the major demagnetization curve when stabilization is achieved by magnetization of the magnet before assembly, and by an applied magnetomotive force after magnetization in assembly. It will be shown that, when the magnet is partially demagnetized for the purpose of stabilization, its operating point lies on a curve which, for convenience, will be called a secondary demagnetization curve. The object of this paper is to discuss the derivation of secondary demagnetization curves for given conditions of stability against demagnetizing forces and their applications to magnet design problems.