. The Bell System technical journal . â == Z= DRY . -1- WEATHER 40 60 80 FREQUENCY- KILOCYCLES Fig. 2âAttenuation variation with weather. The deposits on the wire may be actual ice, or in some cases wetsnow or frost adhering to the wire. Figure 3 shows an example of suchdeposits. Theory shows that the increase in attenuation is caused byenergy losses in the ice itself and that leakage across the insulators isusually a negligible factor. An extensive survey of the effects of ice has been carried on atvarious points throughout the country during the past four years and a TWELVE-CHANNEL OPEN-WIRE
. The Bell System technical journal . â == Z= DRY . -1- WEATHER 40 60 80 FREQUENCY- KILOCYCLES Fig. 2âAttenuation variation with weather. The deposits on the wire may be actual ice, or in some cases wetsnow or frost adhering to the wire. Figure 3 shows an example of suchdeposits. Theory shows that the increase in attenuation is caused byenergy losses in the ice itself and that leakage across the insulators isusually a negligible factor. An extensive survey of the effects of ice has been carried on atvarious points throughout the country during the past four years and a TWELVE-CHANNEL OPEN-WIRE CARRIER SYSTEM 367 large amount of information has been accumulated. These tests haveshown that the shape of the attenuation-frequency characteristic differsconsiderably for different ice formations and even if the ice depositremains the same for a time, the attenuation-frequency characteristicmay vary with temperature as in Fig. 2. The two upper curves of thefigure were measured at different times during the same storm. There. 1
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
