. The practical telephone handbook and guide to the telephonic exchange . is close proximity gives a very large capacityin proportion to the area ofthe plates. The W. W. DeanSystein.—Fig. 133a repre-sents an interesting sub-station circuit used inAmerica. The receiver, itwill be seen, is connected asthe bridge to four resistances joined like those of aWheatstone bridge (forwhich see ChapterXXVIII.). Two of theresistances are non-induc-tive, and two are retarda-tion coils, which stop therapid-speaking currents, sothat these pass through thereceiver and the non-induc-tive resistances. The steady
. The practical telephone handbook and guide to the telephonic exchange . is close proximity gives a very large capacityin proportion to the area ofthe plates. The W. W. DeanSystein.—Fig. 133a repre-sents an interesting sub-station circuit used inAmerica. The receiver, itwill be seen, is connected asthe bridge to four resistances joined like those of aWheatstone bridge (forwhich see ChapterXXVIII.). Two of theresistances are non-induc-tive, and two are retarda-tion coils, which stop therapid-speaking currents, sothat these pass through thereceiver and the non-induc-tive resistances. The steadyfeeding current from thecentral battery passesequally through the twopaths open to it and nonethrough the receiver if allthe resistances are equal. Common Battery WallSets.—The type of sub-scribers instrument mostgenerally used for ex-changes is shownin Fig. transmitter is of the solid-back form, as this is found to give the best resultswith working. It is fitted at the end of a hinged armwith a second hinge, so that it may be adjusted for height,. Fig. 134 124 PRACTICAL TELEPHONE HANDBOOK and at the same time be kept nearly vertical, which is the best position for working. Fig. 135 gives the connections of the Western Electric standard type. Table Set.—The most common form of table set is that shown in Fig. 136, The transmitter, also a solid-back, is hinged at the top toa vertical rod, which can bepulled out about 1J inches foradjustment of height. Theautomatic switch is of a verysimple pattern, the pronglever being attached to a
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Keywords: ., bookcentury1900, bookdecade1900, booksubjecttelephone, bookyear19
