The London, Edinburgh and Dublin philosophical magazine and journal of science . ith the cable standard. It was found that the entire cableand artificial section were equivalent to forty-six miles of thecable standard, and shorter lengths were equivalent to cor-responding lengths of the cable standard. Next, the coilswere introduced into the cable circuit and into the artificialsection, making a cable circuit forty-six miles in length withfour hundred equally spaced loading coils. The transmissionwas greatly improved and found equivalent to the trans-mission over twenty-three miles of cable st
The London, Edinburgh and Dublin philosophical magazine and journal of science . ith the cable standard. It was found that the entire cableand artificial section were equivalent to forty-six miles of thecable standard, and shorter lengths were equivalent to cor-responding lengths of the cable standard. Next, the coilswere introduced into the cable circuit and into the artificialsection, making a cable circuit forty-six miles in length withfour hundred equally spaced loading coils. The transmissionwas greatly improved and found equivalent to the trans-mission over twenty-three miles of cable standard, and in Lines in Telephonic Transmission, 329 addition the articulation was clearer and sharper. In additionto this the side tone at the transmitting end was reduced soas to be hardly noticeable, so that the resuit of loading wasto increase the receiving-end current while decreasing thesending-end current. Tests were made upon different lengthsof the loaded cable and the results of one set of tests areshown in the accompanying diagram (fig. 4). The results were Fur. represented fairly well by a straight line which corresponds to the approximate formula (17). This line shows that theinitial loss was equivalent to nine miles of standard cable,but on account of the greatly reduced attenuation, the loaded 330 On Loaded Lines in Telephonic Transmission. line is better than the unloaded line for all distances greaterthan fifteen miles. If the line representing the experimentalresults is to be parallel to itself, lowered nine miles we havethe curve for a line with terminal transformers, and for thiscase the loading is shown by the experiment to nearly treblethe distance over which transmission of a given volume isobtained, and it actually accomplishes more than that, forthe quality is improved. The tests upon which this diagramis based were made with telephonic transmission and earestimates at the other end of the line and are, of course, moreor less qualitative, since the
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Keywords: ., bookcentury1800, bookdecade1840, bookidlondon, booksubjectscience
