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THE BELL SYSTEM TECHNICAL JOURNAL, JANUARY 1957 



was dictated b}- topography and the desire to locate both it and the 

 second repeater in ponds; thus the transmitting level at Clarenville is 

 substantially lower than the permissible maximum. 



(h) There are equalizing networks at Terrenceville and facilities for 

 their adjustment to compensate for temperature variations. 



(c) Because of the difference between the actual cable attenuation 

 and that for which the repeaters were planned (see section on Attenuation 

 Characteristics) it was necessary to include an equalizer unit in the sea, 

 midway between Terrenceville and Sydney Mines. Loss equivalent to 9 

 nautical miles of cable was also introduced at this point to ensure that 

 repeater No. 16 would be sufficiently far from the shore at Sydney Klines. 



(d) Cable simulators are included in the cable-terminating equipment 

 at Sydney Mines to build out this section to a standard repeater section; 

 the actual cable length was, of course, unknown until the cable was 

 complete. 



Taking into account the existence of the intermediate networks, 

 the repeater spacing is such that when both land and submarine cable 

 sections are at mean temperature the compensation is as accurate as 

 possible. In general the highest frequency is of greatest importance in 

 this respect. Since the low -frequency' channels experience less attenua- 

 tion than the high-frequency channels, it is permissible to transmit them 

 at a somewhat lower level, thereby increasing the load capacity of the 

 amplifiers which is available to the high-frequenc\' channels. 



i 



SYDNEY MINES 



1 



CLARENVILLE 



I 



Fig. 9 — System level diagram. 



