28 



BELL SYSTEM TECHNICAL JOURNAL 



Before leaving Fig. 14 it may be noted that the excess-simulator in 

 Fig. 14d has the same form as though obtained by connecting in 

 series two of the simple form of modified excess-simulator in Fig. 10b 

 having elements CY, Rz and C 2 ", R3", say. This observation suggests 



(a)° — -WWHI-— ° 

 Uvww- 



s' 



(0 



^^HwH 



MAW 



— www— J 



s' 



*0£y 



Fig. 14 — Four Potentially Equivalent 4-Element Excess-Simulators Embodying 

 Shunt-Resistance Modifiers for Extending the Range of Simulation down to Zero 



Frequency 



the possibility of attaining still higher simulative precision for a 

 modified excess-simulator by connecting in series several such simple 

 modified excess-simulators. 



Among the modified complete networks will evidently be found two 

 having respectively the forms already depicted in Figs. 12b and 12c. 



Fig. 15 represents four potentially equivalent complete networks 

 derived from Fig. lid by application of a shunt resistance S" . The 



(a) 



MWHh 



(b)< 



(O 



S" 14.1=1 



1 S 2 S 



— WWW — 1 



rAWW-)(-| 



1 — www— J 



ss 



(d) 



rW\M — |h 



rVWU 

 b VvWV-L'} J 



r^wv-nni 



WW 

 (WW, 



•^ww-Lj^P 



Fig. 15 — Four Potentially Equivalent Complete Networks Embodying Shunt-Re- 

 sistance Modifiers for Extending the Range of Simulation Down to Zero Frequency 



