46 



BELL SYSTEM TECHNICAL JOURNAL 

 Transformation D 



z 2 



A 



bZ 



eZ, fZ 2 



Vv/W WW 



Equivalent when 



(a-by 



(l+a)(l+&) 5 



a 



\+a 





(a-6) a 



(l+a) 2 (l + 6) 

 b 



1 + b 



Transformation E 



VWV 

 Z, 



aZ, 



AAAA/ 



bZ 2 

 WW 



cZ, 



rAAWi 



dZ 2 



AWV 



AAAW 

 Z, 



eZ 



rAAA 

 fZ 2 



Equivalent when 



(2b-M+N)(M+N) 



4bN 

 (M+N-2b)(M-N) 



AbN 



d = 



f 



2b-M+N 



2N 



M+N-2b 



2N 



M=l+a + b, N=V(l+a-\-b) 2 -4ab. 



Transformation F 



Z, aZ, 



rAAAVi 



o Z 2 



L AAAAa J 



bZ 



eZ, 



cZ, 



AAAV 



fZ. 



AAAV-^y — WW 



c= 1+a, 



WW — 



Equivalent when 



a(l+a)(l + 6) 2 



/• = 



&(l+a) 2 (l + &) 



