886 



THE BELL SYSTEM TECHNICAL JOURNAL, JULY 1956 



_i 



LLI 

 CO 



o 



UJ 



Q 



tf) 

 O 



_l 



Q 



a. 

 < 



cr 

 O 

 u. 



0.4 0.8 1.2 1.6 2.0 2.4 2.8 



MAGNETIZING CURRENT IN AMPERES 



3.2 



3.6 



Fig. 7 — Forward loss versus magnetizing current. 



Using the experimental values 4:tMs — 1,700 gauss and internal mag- 

 netic field = 300 oersteds, the frequency at which ferromagnetic reso- 

 nance occurs was estimated to be about 2200 mc/sec. This value is suf-ii 

 ficiently far from our operating range (5,925-6,425 mc/sec) that we| 

 would expect a negligible loss contribution due to resonance absorption.}, 

 This is confirmed by the low forward loss actually observed. 



B. Ferrite Height 



We have already pointed out that when the ferrite height is reduced 

 from full height a more reasonable VSWR is obtained. This is due to the 

 fact that we have relieved the stringent boundary requirements at the 



60 



^ 50 



LU 

 O 



UJ 40 



if! 30 



(/) 



o 



_J 



UJ 20 

 CO 

 CC 

 UJ 



> 



yj 10 



0.4 0.8 1.2 1.6 2.0 2.4 2.8 3.2 3.6 



MAGNETIZING CURRENT IN AMPERES 



Fig. 8 — Reverse loss versus magnetizing current. 



