File:Bell telephone magazine (1922) (14776059033).jpg

Identifier: belltvol20elephonemag00amerrich (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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aerial surveysto guide the field work in the selectionof a suitable route through this terri-tory, particularly the difficult moun-tain terrain. The heavy snowfall inthis region is expected to be an ob-stacle to maintenance work, and forthis reason the cable will follow ex-isting highways in the higher and morerugged sections. Cable Details Ihe detailed arrangements of thetranscontinental cables for the opera-tion of type-K carrier systems are es-sentially the same throughout thelength of the route. One cable con-tains, in various sections, 54 to 88pairs of paper-insulated 19-gauge con-ductors surrounded by lead sheathover which is placed a steel tape andjute and other protection. This cableis used primarily for one direction ofcarrier transmission. Certain of thepairs are loaded for use as voice-fre-quency plant maintenance circuits or,in some sections, for message circuitsbetween intermediate points. The sec-ond cable, of similar construction, con-tains an equal number of conductors
Text Appearing After Image:
< oNsrm ( rioN oi- thk (IableThis specimen of a typical section of one ofthe twin cables consists (reading up from thebottom) of: 1, jute protection; 2, thermo-plastic protection; 3, steel gopher tape;h, lead sheath; 5, double paper wrapping ofcore; 6, the conductors for the opposite direction of carriertransmission and varying numbers ofloaded conductors. In some sections,where a sizable number of voice-fre-quency circuits are required, this ca-ble may be quadded. Some 1,500-foot lengths of cablewere used in the first sections plowedin. In general, long pieces of cablecan be buried more economically than 216 Bell Telephone Magazine NOVEMBER short lengths. Accordingly, trials of3,000-foot lengths were made, andsince it was found that these couldbe satisfactorily handled, 3,000-footlengths are now generally being sup-plied and placed. W HiLE the cable is being manufac-tured, great care is taken to avoid de-viations from uniformity in the elec-trical characteristics of the conduc-tor

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