18 THE BELL SYSTEM TECHNICAL JOURNAL, JANUARY 1952 



sample and is not dependent directly on the applied magnetic field. 

 Fig. 7 shows the dependence of rotation upon magnetization for a 

 sample of manganese zinc ferrite, and indicates that after the sample is 

 saturated, the rotation is sensibly independent of the applied magnetic 

 field. In addition, the complex dielectric constant and the saturation 

 magnetization of this sample were measured. From these the rotation 

 per centimeter path can be computed from the above theory using 



ROTATABLE 

 SECTION 



FERRITE 

 WINDING- 



STATIONARY 

 PROTRACTOR 



RADIAL VANE TO 



ABSORB VERTICALLY 



POLARIZED WAVES 



TAPERED TRANSITIONS 

 TO REDUCE REFLECTIONS 



RADIAL VANE TO 



ABSORB HORIZONTALLY 



POLARIZED WAVES 



Fig. 6 — Detail of test chamber in which rotations were measured. 



120 



a. 



13 



"oj 

 Z\L 

 zl 



Ol- 



< UJ 



&^ 



cctr 



UJ 



Q 

 < 



500 



2500 



1000 1500 2000 



MAGNETIC FIELD IN OERSTEDS 



Fig. 7 — Angle of rotation versus applied magnetic field for a thin disc of man- 

 ganese zinc ferrite. 



