226 



BELL SYSTEM TECHNICAL JOURNAL 



which give an analysis of the different types of Hne losses, (a) the 

 "series" losses due to heat dissipation in the conductor and the loading 

 ceils, which are proportional to the square of the line current, (6) the 

 "shunt" losses due to heat losses in the dielectrics, which are pro- 

 portional to the square of the line voltage, and (c) the lumpiness effects 

 i\\\Q to internal reflections. The large reduction in the series losses 



80,000 



1000 1500 2000 2500 3000 

 FREQUENCY-CYCLES ! 



0.18 0.36 0.53 0.71 0.89 10 



RATIO OF FREQUENCY TO CUT-OFF FREQUENCY 



Fig. 2 — \'elocit\-frefiiicncy characteristics of loaded and non-loaded No. 19 A. \v. g. 



cables of Fig. 1 



accomplished l)y the loading is clearly indicated in the diagram- 

 A corresponding proportional increase in the shunt dissipation loss also 

 occurs, but as previously noted this effect is small in absolute mag- 

 nitude relative to the decrease in the series losses. It is interesting 

 to note that the particular type of loading illustrated in Fig. 1 so 

 increases the transmission efficiency of No. 19 A.W.G. cable that 

 the loaded circuit can l)e used for distances about four times the 

 permissible length of the non-loaded circuits. To obtain this in- 

 creased transmission range without loading would require wires 

 about eight times as heavy, i.e., No. 10 A.W.G. 



