. The practical telephone handbook and guide to the telephonic exchange . amp;a 1^ Fig. 303 minals are mounted four at one end and two at the other,as shown in Fig. 305, which shows the coils as thoughwound on two separate cores. On the 11b the terminals areall mounted at one end, so that the repeaters can be fittedon a wall rack where only one side can be reached. Each ofthe four coils in these repeaters has a resistance of 42 ohms. A newer and rathermore efficient form ofrepeater is known asthe toroidal. Thisis a ring form of re-peater, which has beenreferred to in ChapterXVI., Fig. 239. Iti
. The practical telephone handbook and guide to the telephonic exchange . amp;a 1^ Fig. 303 minals are mounted four at one end and two at the other,as shown in Fig. 305, which shows the coils as thoughwound on two separate cores. On the 11b the terminals areall mounted at one end, so that the repeaters can be fittedon a wall rack where only one side can be reached. Each ofthe four coils in these repeaters has a resistance of 42 ohms. A newer and rathermore efficient form ofrepeater is known asthe toroidal. Thisis a ring form of re-peater, which has beenreferred to in ChapterXVI., Fig. 239. Itis covered with a circular iron casing, and two repeaters aremounted on a base-board 4 inches by lOf, so that theyoccupy exactly the same rack space as two No. 11 resistance of each coil is only 22J ohms in this connections are similar to those of Fig 305. Condenser Rack.—This frame is for the accommodation ofthe 2J-microfarad condensers used in connection with theincoming junction lines. It is 6 feet wide, and has a capacityfor 1080 Fig. 304 30o PRACTICAL TELEPHONE HANDBOOK These condensers are each contained in tinned iron cases,which are 7| inches long, k\\th inches wide and y-g-ths of aninch thick. The terminal tabs are fitted on a strip of ebonitescrewed to an end lid. The condensers should withstand avoltage of 200 and have an insulation resistance of at least150 megohms. The condensers are laid on their longest edges on the shelves,so that the ends with the terminal tabs all come to one frame is 7 feet 3J inches wide and 7 feet 10 inches is divided into 2 panels, each of which has 10 shelves, each Ring. ( r,e Call Pl-L a=J \jji/i^x\xm} /7T7Trpttnr] ~r Fig. 305 of these shelves accommodating 54 condensers, or a total of1080. In addition to the frames, etc., so far described, the apparatus -room at Barnsbury, also contains the wire chiefs desk, shownon the right of Fig. 301, on which is fitted apparatus for th
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Keywords: ., bookcentury1900, bookdecade1900, booksubjecttelephone, bookyear19
