PROPORTIONING OF CIRCUITS FOR ATTENUATION 



265 



same material, so that // ocjuals unity, the optimum values are approxi- 

 mately 



P=-^=5.4; 



.46. 



(33), (34) 



The optimum diameter and spacing ratios for different values of the 

 conductivity ratio n are shown in Figs. 8 and 9. For copper conduc- 



0.3 0.4 0.5 I 2 3 4 5 10 20 30 40 50 



RATIO OF CONDUCTIVITIES (INNER CONDUCTORS TO SHIELD, '^l/^^ ) 



Fig. 8 — Variation of optimum diameter ratio of shielded pair with conductivity ratio. 



0.3 0.4 0.5 



20. 30 40 50 



RATIO OF CONDUCTIVITIES (INNER CONDUCTORS TO SHIELD, ^j/^i^-) 

 Fig. 9 — ^ Variation of optimum spacing ratio of shielded pair with conductivity ratio. 



