. The Bell System technical journal . m-ployed in the telephone plant. This permits the use without modifica-tion of certain standard pieces of equipment, such as jack strips, fusepanels, meter panels, audio frequency filters, and the like. It alsopermits the removal and repair or substitution of units with a minimumof delay. The set is required to receive signals at three fixed frequen-cies in the range 9000 to 21,000 kilocycles. This involves connectionswith three antennas through three separate transmission lines. Thetuning of the antenna and transmission line terminations are ratherlengthy
. The Bell System technical journal . m-ployed in the telephone plant. This permits the use without modifica-tion of certain standard pieces of equipment, such as jack strips, fusepanels, meter panels, audio frequency filters, and the like. It alsopermits the removal and repair or substitution of units with a minimumof delay. The set is required to receive signals at three fixed frequen-cies in the range 9000 to 21,000 kilocycles. This involves connectionswith three antennas through three separate transmission lines. Thetuning of the antenna and transmission line terminations are ratherlengthy processes requiring precise adjustments. In order to facilitatequick changes from one operating frequency to another without intri-cate tuning operations, the first stage of radio amplification is providedin triplicate and the switching is done between the first and secondstage. Thus the antennas are permanently connected to the set andtheir adjustments remain undisturbed. The circuits of the second 284 BELL SYSTEM TECHNICAL JOURNAL. ca unS CQ > co
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
