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. The telephone system of the British post office. A practical handbook . en, necessary to have the wires both in geographical and in thesection order. In order to accomplish this object the double row of linetags is utilised. The right hand set of tags contains the whole of thetrunks in the exchange, and the left hand set of tags contain the whole ofthe positions upon the switch sections. As jive trunks are placed uponeach section we see that each strip corresponds to a section. It hasalready been pointed out that the central set of five boles upon the testboard are used for through wires, co
. The telephone system of the British post office. A practical handbook . en, necessary to have the wires both in geographical and in thesection order. In order to accomplish this object the double row of linetags is utilised. The right hand set of tags contains the whole of thetrunks in the exchange, and the left hand set of tags contain the whole ofthe positions upon the switch sections. As jive trunks are placed uponeach section we see that each strip corresponds to a section. It hasalready been pointed out that the central set of five boles upon the testboard are used for through wires, counter-cabinet, and such-like Junctions and service wires take up two rows, and thus there are onlyten positions left for the trunks (, the equipment of two sections). Theextreme left hand and extreme right hand strips are therefore devoted totrunk lines. Upon the left side of each of these strips are the trunks andsections in geographical order, and upon the right side in the sectionorder. The right strip then accommodates the wires from section I. The. Figure 124. right strip at the right hand side accommodates the wires from sec-tion II. If there are forty sections to be accommodated, then the extremeright and left strips of each test tablet will be marked consecutively,section I. to XL. To take a case in point, let us suppose that we have to deal with twotrunks, Todmorden and Bacup, coming into our ofBce by different routes,the former being No. i on section I, and the latter No. i on section Todmorden lines come in upon the right hand tags and are joinedthrough to the left ones by means of bare wire; thence they pass to theirposition upon the test board. Here they are linked through to the switchsection—, the top set of holes must be joined to the first position onsection XII. This is accomplished by taking a pair of wires from theright hand side of the left tags to the right hand side of the first positionon section XII. Similarly, Bacup secti
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Keywords: ., bookcentury1900, bookdecade1900, booksubjecttelepho, bookyear1901