CROSSTALK BETWEEN COAXIAL CONDUCTORS 



381 



section. When combined with a transposition the crosstalk in two 

 sections is from 13 to 27 db below either individual section over the 

 frequency range. Such a reduction is possible only because AB andA'B' 

 are so nearly equal. 



95 

 100 

 105 

 110 

 115 

 120 

 125 

 130 

 135 



:3i4o 



UJ 



ffl 



O 145 



UJ 



O 



-r 150 



40 50 60 



80 100 150 200 300 400 500 600 



FREQUENCY IN KILOCYCLES PER SECOND 



Fig. 12 — Effect of a transposition on far-end crosstalk in a 24,000-foot length with 

 all tertiary circuits suppressed at the transposition. 



In contrast, BA and B'A' may be seen to differ considerably from 

 each other at the higher frequencies. As a result, the transposition is 

 not nearly so effective in that range. The improvement at the lower 

 frequencies where it is needed most is still about 20 db. 



