File:Bell telephone magazine (1922) (14753543351).jpg

Identifier: belltelephonemag19amerrich (find matches)
Title: Bell telephone magazine
Year: 1922 (1920s)
Authors: American Telephone and Telegraph Company American Telephone and Telegraph Company. Information Dept
Subjects: Telephone
Publisher: (New York, American Telephone and Telegraph Co., etc.)
Contributing Library: Prelinger Library
Digitizing Sponsor: Internet Archive

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house connection and the policy isfollowed of avoiding trees as far aspracticable, it is inevitable that somedamage to aerial house connectionsshould occur at these times. In orderto insure against interruption of serv-ice from such causes, the TelephoneCompany and the individual sub-scriber frequently cooperate to placethe house connection underground. Coping With Ice Loads JM EEDLESS to say, to provide econom-ically against damage and service in-terruptions due to ice and wind re-quires an intimate knowledge of theconditions which must be met. Theseverity and frequency of storms mayvary widely between adjoining areas.The direction of the line with respectto the winds which prevail at the timeof ice storms is also important, as isthe effect of wind breaks offered byhills and woods. Finally there is thequestion of how great an expenditurefor extra strength can be justifiedfrom a service insurance standpoint;a transcontinental circuit, for exam- 19^0 Outwitting Open Wires Worst Foe 243
Text Appearing After Image:
Fig. 12. H FIXTURES Construction on the Argentine Pass, in the Rocky Mountains, to withstand unusual stresses pie, justifies greater strength than anexchange circuit only half a mile long.First thought must be given to thewires themselves. In the Bell System,hard-drawn copper and galvanizedsteel wire are the types used chieflyfor open wire circuits. Size for size,steel wire is stronger than copper andis better mechanically than copper inother ways; but copper wire, having amuch lower electrical resistance perunit of length, has important advan-tages from the standpoints of bothvoice transmission and the transmis-sion of the necessary signals betweenthe central office and subscriber orbetween central offices. Under manyconditions, however, galvanized steelwire is a highly satisfactory materialfor open wire construction, particu-larly in exchange and rural lines.This is particularly true now that gal-vanized wire can be obtained withvarious weights of galvanizing de- signed to meet diff

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