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BELL SYSTEM TECHNICAL JOURNAL 



general way, of the loaded cable. This is shown by the attenuation 

 curve of one of the 1921 cables which is given in Fig. 5 for comparison. 

 The d-c. properties of the laid cable are shown in Table IV. 



TABLE II 

 Core Structure of Key West-Havana Cable No. 4 



Central Conductor 



Central Wire Diameter .138 In. 



Surrounds 6 tapes .0142 in. X .079 in. 



Weight of Whole 505 Ibs./n.m. 



Diameter of W^hole 167 in. 



Impregnating Compound 0024 in. thick 



Insulation 



Weight (Including Compound! 677 Ibs./n.m. 



Outer Diameter 614 in. 



Fabric Tape 010 in. thick 



Protective Tape (Copper) 1 in. X .004 in. with 10% 



overlap 



Weight 209 Ibs./n.m. 



Return Conductor 6 tapes .319 in. X .019 in. 



Weight 845 Ibs./n.m, 



Outer Diameter 681 in. 



Ozokerite Tape 



Outer Diameter 704 in. 



TABLE III 

 Armor for Key West-Havana Cable No. 4 



I.e. = lead covered. 

 e.w.t. = each wire taped. 



TABLE IV 



Conductor Resistance, Dielectric Resistance and D-C. Capacity of Key 

 West-Havana Cable No. 4 as Laid 



Conductor (Central) Resistance 242 ohms 



Dielectric Resistance 1090 megohms 



Capacity 22.52 microfarads 



One respect in which the present cable differs from the 1921 cables 

 is that it has a single-core termination instead of an unbalanced-type 

 twin-core termination.^ Experience with the 1921 cables has shown 



*" Extraneous Interference on Submarine Telegraph Cables," J. J. Gilbert, Bell 

 System Technical Journal, Vol. 5, p. 404, 1926. 



