PLANNING AND OVER-ALL PERFORMANCE 15 



As is apparent from the previous discussion, it was found that the 

 basic features of a deep-water design had been completed by the Bell 

 System. Not only had many of the components been under laboratory 

 test for many years, but a complete system had been operating for 2| 

 years between Havana and Key West. To use a phrase coined at the time, 

 the design had proven integrity. 



Because of the years of proof and the conservative approach adopted 

 to assure long life, the design was far from modern. The electron tubes, 

 for example, had characteristics typical of tubes of the late 1930's, when, 

 in fact, they were designed. Similarly, other components were essentially 

 of prewar design. 



The Post Office, on the other hand, had pioneered shallow-water 

 repeaters and were pre-eminent in tliis field. Their deep-water designs 

 were still evolving and had not yet been subjected to the same rigorous 

 tests as the Bell System repeaters. This later evolution, however, made 

 possible a much more modern design. The electron tubes, for example, 

 had a mutual conductance of 6,000 micromhos as compared to about 

 1 ,000 in the Bell System repeater, and thus had a potentiality for much 

 greater repeater band widths. 



It was apparent from these reviews that only the American design was 

 far enough advanced to assure service at an early date. It also appeared 

 to have the integrity so essential to such a pioneering and costly effort 

 as a transatlantic cable. On the other hand, the more modern Post 

 Office design had many elements of potential value. If deep-water laying 

 hazards could be overcome and proof of reliability established, it gave 

 promise of greater flexibility and economy for future systems. 



It was on these grounds that Dr. Mervin Kelly for the Bell System 

 and Sir Gordon Radley for the Post Office jointly recommended that 

 the Bell System design be used for the long length and great depths of 

 the Atlantic crossing and the Post Office design be used for the New- 

 foundland-Nova Scotia link where the shallower water afforded less 

 hazard and better observation of this potentially interesting design. The 

 decision to use the Post Office design was subject to technical review after 

 deep-sea laying tests and further experience with circuits and com- 

 ponents. This review, made in June of 1954, confirmed the soundness 

 of the original recommendation. 



SYSTEM PLANNING 



Planning of the individual systems began as soon as the technical 

 decision just mentioned had been reached. By the time administrati\'e 

 agreements had been reached and the contract signed on November 

 27, 1953, both parties were ready to set up system objectives and an 



