CHARACTERISTICS OF TOLL TELEPHONE CABLES 



321 



extending to much higher frequencies. In the laboratories measurements 

 were made on 16 and 19-gauge pairs in reel-lengths at frequencies up to 

 about 3000 kilocycles. Field data at frequencies from 100 kc. to 2000 kc. 

 were obtained on 16-gauge and 19-gauge pairs in cables about 3 miles long at 



200 



400 



1400 



600 800 1000 1200 



FREQUENCY- KILOCYCLES 



Fig. 21 — Attenuation of 16 gauge cable pairs 

 A, on reel, 247 feet; B, fourteen reels, 1.3 miles; C, aerial cable, 3.6 miles, Ticonderoga, 



N. Y. 



Ticonderoga, New York. A third set of data was obtained from measure- 

 ments on 7000 feet of a special type (61-pair) of 16-gauge cable on reels in 

 the laboratory under controlled temperature conditions. Figure 21 shows 

 the attenuation values to 2000 kc. obtained in the three sets of 16-gauge 



