File:Bell telephone magazine (1922) (14569939887).jpg

Identifier: belltelephonemag13amerrich (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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ufactured is at leasttwice that of new wire only six years ago, and after aging theequivalent of three or four years in the plant the comparisonfavors the present wire by a ratio of about 5 to 1. This meansthat the present wire should be better when it is three or fouryears old than was new wire six years ago, and it indicates along useful life for the present wire. When rubber compoundof the general type under discussion has greater compressivestrength it also has greater toughness, which means greaterability to endure the kinds of abuse to which drop wire isordinarily exposed. Improved Protective Covering Even though the insulating compound has been much im-proved, it still needs further protection against its worst ene-mies: rubbing tree limbs, and sunlight. The means for ac- 43 BELL TELEPHONE QUARTERLY complishing this is to enclose it in a lightproof covering thatwill resist abrasion and withstand a wide variety of weatherconditions. For many years the covering has consisted of a
Text Appearing After Image:
Figure 3. Distribution from Aerial Cable Terminal Illustrating the Use ofTwisted Pair Drop Wire and Dead End Ties (No. 14 Type Cable Terminal). cotton yarn braid which has been treated with weatherproofingmaterials. These materials and the methods of applying themhave undergone a number of changes throughout the years but, 44 THE ROLE OF DROP WIRE similar to the experiences with insulating compounds, quanti-tative measurements of results had to come before there couldbe definitely predictable improvements in serviceability. To Ml-^r4.,,

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