96 



THE BELL SYSTEM TECHNICAL JOURNAL, JANUARY 1951 



There is another type of negative impedance converter circuit which 

 should not be confused with the converter circuits mentioned heretofore. 

 This type was disclosed by Charles Bartlett in the March 1927 issue of the 





z, 



IDEAL 



CONVERTER 



OF RATIO 



Rp+Z, 



(a) (b) 



Fig. 4 — A negative impedance converter and its equivalent circuit. 



(a) 



f=o 



f=oo 



-Ri- 

 -JX (b) 



jX f= — L 



o-AAA^ 



-* :i 



R'< Lg c^ 



1 1 — I 



(g) 



Fig. 5 — Impedance loci. 



-jX 



Journal I.E.E. pages 373 to 376. The Bartlett converter consists of a T 

 network of equal resistances, one of them negative. To construct such a 

 converter there must be available a negative resistance element. Over a 



