. The Bell System technical journal . hing tech-nically insurmountable either in going to considerably higher fre-quencies or in utilizing the lower frequency range, which is now idleexcept for the use of the d-c. path for purposes of transmission regu-lation and fault location. Important factors influencing the selectionof the upper frequency are the crosstalk, which depends on the numberof pairs utilized for carrier in one cable and the extent to which specialcrosstalk balancing means are used, and the attenuation, which largelycontrols the spacing between repeaters. Factors affecting the lo
. The Bell System technical journal . hing tech-nically insurmountable either in going to considerably higher fre-quencies or in utilizing the lower frequency range, which is now idleexcept for the use of the d-c. path for purposes of transmission regu-lation and fault location. Important factors influencing the selectionof the upper frequency are the crosstalk, which depends on the numberof pairs utilized for carrier in one cable and the extent to which specialcrosstalk balancing means are used, and the attenuation, which largelycontrols the spacing between repeaters. Factors affecting the lowerlimit include the difficulty of maintaining accurate transmissionregulation over the whole frequency range, and the design of therepeater, which becomes harder as the ratio of maximum to minimumtransmitted frequency is increased. The frequency range between 12 and 60 kilocycles accommodates12 speech channels, each occupying a gross band of 4 kilocycles. The A CARRIER TELEPHONE SYSTEM FOR TOLL CABLES 83 OO <J) ii = 1 f M 1 1 M M. a 00 11 Q. z R Q -J < (u r; in < ^5 DD^ rTTTTTTTTT
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
