CHARACTERISTICS OF TOLL TELEPHONE CABLES 



323 



The curves of the change in attenuation per degree F. per mile 

 (db/l°F./mi) as shown by Figs. 23 and 24 are highly dependent upon the 

 temperature, showing that at these high frequencies the attenuation is de- 

 cidedly nonlinear with temperature in the toll cables. 



800 



900 1000 1100 



300 400 500 600 700 



FREQUENCY- KILOCYCLES 



Fig. 23— Variation in attenuation at different temperatures for 1°F. change in 



temperature; aerial cable — 16 gauge pairs 



O .010 



y 50 100 150 200 250 300 350 400 450 500 550 600 650 700 



FREQUENCY- KILOCYCLES 



Fig. 24— Variation in attenuation at different temperatures for I'F. change in 

 temperature; aerial cable — 19 gauge pairs 



Toll Entrance Cable 



The insertion losses measured between 125-ohm resistances on various 

 lengths of 13, 16 and 19-gauge toll entrance cables at Denver, Colorado, 

 are shown in Fig. 25. The data have been reduced to a per-mile basis by 



