oi'iiK.iiioN ()!■ I iir.h-Mioxic r.icri'M Tt'nr. circuits' 453 



In the si)ecial case when the input and delected frequencies are 



— and — , respecti\el\-, and where Sj^r^, : 

 2k 27r 



Qh = 



Qs = 



1 



jhC 



jsC 

 1 



jsC 

 i^ = leak resistance 

 C = capacity in parallel with R 

 Then, the optimum size for the condenser, C, is easily shown to be 



C' = 



, (approx.) 



(50) 



200 400 eOO 600 K)00 tzoo 



CAPACITY OF CCID-LEAK CONOEKJSER 



1400 1&00 



^^( 



Fig. 6 — Optimum size of grid-leak condenser 



Experimental Conditions: 

 /z=27rX (30000 ±500) 

 5 = 27rX(1000) 

 Grid-leak = i? = 10" ohms 

 r„ = 10^ ohms 



Then the optimum size of the 

 grid-leak condenser, C, is: 



r^ = 



V2 (J?+ 



C„„,=361uu farad 



