estimated breaking strength of 2800 pounds. FM telemetering 

 with a seawater return is used to send a large number of 

 signals over several miles of cable. This technique offers 

 some definite advantages, particularly in simplifying the 

 connector problem, although its use does require a complex 

 electronic telemetering system both within the instrument 

 package and at the shipboard recording station. 



These possible designs were considered at length, and 

 discussed with members of organizations engaged in oceano- 

 graphic research. As a result, it was decided to select 

 a double-armor cable, with either a co-axial or multi-conductor 

 core, as the basic configuration for the system. This selec- 

 tion does not preclude the possibility of using a single- 

 strand combined strength and electrical conductor, however, 

 since the basic design can be readily adapted to such use. 



Consideration was also given to the problem of adding 

 fairing to the cable to reduce its drag and vibration. Al- 

 though the use of fairing seriously complicates the problems 

 of storage and handling, and adds significantly to the cost, 

 the achievement of great depths at reasonable towing speeds 

 without the use of fairing is impractical. Unfortunately, 

 obtaining comparisons of configurations that might satisfy 

 requirements for depth and speed involves laborious calcu- 

 lations, using methods as described in (3) . The 

 tediousness of this task motivated the development of the 



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