678 



BELL SYSTEM TECHNICAL JOURNAL 



©; 



1^ °''^' ($)| 



Eb 



i'$)V;,9i 



^ Ec 



Fig. 6 — Equivalent circuit — first-order effects. 



where 



rpL= {P^ea^-\-Phebl^+P&ep^+P^ealehl-\-Piealep^-\-P^ehlepl)rp 

 raM={Aieai^+A5ebi^-]-A6epi^-^A7eaiebi+Aseaiepi-]-A9ebiepi)ra 

 rbN= {Bieal+Bieb^ -\-B6epi-'t-B7eaiebi-\-B8eaiepi+B9ebiepi)rb 

 which in view of (30), (31) and (32) may be written 



T T, / r I \2 I 1 / dfipa . dHpa\ „ 



TpL = rpPeiiipaCai + Mpb^bi + ^pv + 2 \ d£" ^^^ d£" / 



I 1 / dfJLpb , dlJ.pb\ „ 2 j_ ( dfJ.pb . dfJ,pa \ 



-^-dEp''''''''^'dEp '''' 



, 1 / dHap , ^Map \ 2 I ^^°'' « o 



1 / ^Mt 





dfJLba 



Cal- 



(37) 



(38) 



(39) 



(40) 



