CHAPTER IV 



The Establishment of a Transcontinental Network of 

 Repeatered 165 Mil Lines 



This concluding part of the transmission development story is mainly 

 concerned with the establishment of a country-wide network of 165 mil 

 lines interconnecting all important cities, following the completion of the 

 New York-San Francisco Une. The American Company engineering de- 

 partment took the initiative in this work, and the Western Electric research 

 and development groups handled their parts of the work under Jewett in 

 accordance with their usual organization responsibilities. During the early 

 part of this period, December 1916, Jewett became the chief engineer of 

 the Western Electric Company. Early in 1921, he became Vice-President 

 of the W'estern Electric Company in charge of the telephone department, 

 having over-all responsibility for engineering and manufacture. 



Planning a Backbone Network 



Immediately after the opening of the New York-San Francisco line, the 

 making of plans to exploit the new developments and the new engineering 

 knowledge got well under way. On March 1, 1915, Carty approved the 

 American Company Work Order 8230, "Network of No. 8 Gauge Circuits 

 Equipped With Telephone Repeaters Connecting All Important Cities of 

 the United States." The work was to consist of: 



(A) Determination of the best routes, and the sequence of installation. 



(B) Determination of changes in loading and transpositions to fit these 



lines for repeater use. 



(C) Choice of repeater equipment and circuit arrangements. 



(D) Determination of the best operating methods. 



When this project was authorized it was expected that loaded 165 mil 

 open-wire circuits would be universally used in the backbone network. 

 This part of the plan, however, was soon modified in consequence of trans- 

 mission studies which showed even more attractive possibilities in the use 

 of non-loaded 165 mil lines having additional repeaters to make up for the 

 mcreased line losses. The expected advantages of this proposed change 

 were: 



(a) Elimination of the telegraph flutter impairments that were quite 

 troublesome on the long loaded circuits. 



(b) More uniform attenuation and impedance characteristics under 

 varying weather conditions. 



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