. BSTJ 1: 1. July 1922: Philadelphia-Pittsburgh Section of the New York-Chicago Cable. (Pilliod, James J.) . S< JtSfc-H «Llf S^i1 V§ 391 , , r 1 ~ *, w*• / fl «V!r ii iK <Bri l|fci|.g-:lfj s?8 .*!??;•-— i 7- - ~ V <fi A*-J x .. Fig. 24—Group of Repeaters at Reading, Pa. and examples would be such circuits as New York-Pittsburgh or NewYork-Chicago. Both of these types of circuits may be operated on No. 19 A. W. facilities which may be either physical or phantom circuits. Fig. 24 shows a group of repeaters installed in the office at Reading,Pa., and Fig. 25 shows one of the
. BSTJ 1: 1. July 1922: Philadelphia-Pittsburgh Section of the New York-Chicago Cable. (Pilliod, James J.) . S< JtSfc-H «Llf S^i1 V§ 391 , , r 1 ~ *, w*• / fl «V!r ii iK <Bri l|fci|.g-:lfj s?8 .*!??;•-— i 7- - ~ V <fi A*-J x .. Fig. 24—Group of Repeaters at Reading, Pa. and examples would be such circuits as New York-Pittsburgh or NewYork-Chicago. Both of these types of circuits may be operated on No. 19 A. W. facilities which may be either physical or phantom circuits. Fig. 24 shows a group of repeaters installed in the office at Reading,Pa., and Fig. 25 shows one of the four-wire repeater units in somewhatgreater detail. NEW YORK-CHICAGO CABLELine Impedance SI In order that networks may be used to balance the lines for repeateroperation, it is necessary as a practical proposition that the impe-dance characteristics of the lines be fairly uniform over the range oftelephone frequencies. The solid line in Fig. 26 shows the resist-ance component of the impedance of a No. 19 loaded cable circuitwith all loading coils in place. The solid line in Fig. 27 shows the. Fig. 25—Assembly of Four-Wire Repeater Apparatus / /- 1 -. -/ V .---- -- , ia --^, \ - .J. 1500 2000 Coil »in»cto In 13th iictioh C«uiv«llNi lNooet»N« Fig. 26—Line Characteristics—A Cable Circuit in Normal Condition 82 BELL SYSTEM TECHNICAL JOURNAL resistance component found in impedance measurements on the samecircuit with one coil omitted at the thirteenth loading point fromthe end at which the tests were made. It will be noted that in thelatter case the characteristics of the circuits vary greatly with would therefore be very difficult as a practical proposition to buildup a network that would balance lines in this condition, and suchvariations in the electrical characteristics of a circuit impair thequality of telephone transmission, as the currents of different fre-quencies are differently affected. The necessity for careful main-tenance work in pro
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttelepho, bookyear1922
