966 THE BELL SYSTEM TECHNICAL JOURNAL, JULY 1954 



^1 



toko 





0.2 



0.1 



0.2 0.4 



0.6 0.8 



1.0 



d 



1.4 



1.8 2.0 



Fig. 10 — Ratios of reverse attenuation for a flat helix separated from the 

 ferrite by a distance Xo to the reverse attenuation at Xq = 0. Computations made 

 from the approximate slope-formuhi for the loss, where applicable, (a) p = 0.2. 

 (b) p = 0.8. In (a) all applicable o- values lie in the shaded region. 



For example, if /3 > /3i , and the medium occupies all space from a finite 

 r to infinity 



jcoei K o(air) —jcoeiKi(air) 



i^TM — 



ai Ko(air) 



aiKo(air) 



(23) 



where ai = V(8- - /3r. 



The field components of the TE field are determined by equations 

 (20b), (20d) and (20f). Elimination of E^ and Hr from these gives 



1 d dH, , / 2 2 PHd\ 



r dr dr \ r 



0, 



(24) 



where ^/ = wVei (1 - ph). The term /?/ - jS" in the bracket is already 



