. The Bell System technical journal . 0 < UJLUZ I- CCO -i y 9<c J-is! NEW SINGLE CHANNEL CARRIER TELEPHONE SYSTEM 171 attenuation-frequency characteristics for four commonly employedgauges of open-wire line under dry and wet weather conditions, re-spectively, at a temperature of 68° F. These curves are for 12-inchspaced copper wires equipped with the type of insulators ordinarily. Fig. 9—Repeater panel—front view. ■ DRYWEATHER ^o^ ■^ ^ ^ \6>- ^ WET WEATHER ^ .^ ;^ ^ ^ ^^ ^ 1> ^ ^ ^ ^ ^ ^ ^ .y^ 8 10 12 0 2 4 6 FREQUENCY IN KILOCYCLES PER SECOND Fig. 10—Attenuation of open-wire
. The Bell System technical journal . 0 < UJLUZ I- CCO -i y 9<c J-is! NEW SINGLE CHANNEL CARRIER TELEPHONE SYSTEM 171 attenuation-frequency characteristics for four commonly employedgauges of open-wire line under dry and wet weather conditions, re-spectively, at a temperature of 68° F. These curves are for 12-inchspaced copper wires equipped with the type of insulators ordinarily. Fig. 9—Repeater panel—front view. ■ DRYWEATHER ^o^ ■^ ^ ^ \6>- ^ WET WEATHER ^ .^ ;^ ^ ^ ^^ ^ 1> ^ ^ ^ ^ ^ ^ ^ .y^ 8 10 12 0 2 4 6 FREQUENCY IN KILOCYCLES PER SECOND Fig. 10—Attenuation of open-wire side circuits—12-inch spaced copper wire withdouble petticoat glass insulators. employed for toll circuits. Changes in temperature also afifect theattenuation, the loss increasing as the temperature rises. The varia-tions due to changes in temperature are, however, smaller than thosedue to changes from dry to wet weather and are more likely to occur 172 BELL SYSTEM TECHNICAL JOURNAL gradually. It is apparent that the variations in attenuation withweather increase with the length of the system, and that more frequentadjustments will be required on the longer systems to maintain theoverall circuit net loss within given limits. The carrier frequency attenuation of cable circuits is much greaterper unit length than that for open-wire lines. Hence, the lossesintroduced by
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
