. The practical telephone handbook and guide to the telephonic exchange . 160.—Full size. B D FT? V R Eth p r\ tfc] w%\ iP^lPiH nr^ K Fig. 161.—Full size and 162 show a form in which the restoring is done automati-cally by means of a local battery current. The indicator is a kind of double drop, being similar to atubular drop, o, with another shorter ironclad coil, R, attachedto one end of it, the latter being fitted with a heavy armature,a, pivoted at the bottom, and a very light aluminium shutter,p, pivoted at the top. The core of r is prolonged, and its end 148 PRACTICAL TELEPHONE HANDBOOK
. The practical telephone handbook and guide to the telephonic exchange . 160.—Full size. B D FT? V R Eth p r\ tfc] w%\ iP^lPiH nr^ K Fig. 161.—Full size and 162 show a form in which the restoring is done automati-cally by means of a local battery current. The indicator is a kind of double drop, being similar to atubular drop, o, with another shorter ironclad coil, R, attachedto one end of it, the latter being fitted with a heavy armature,a, pivoted at the bottom, and a very light aluminium shutter,p, pivoted at the top. The core of r is prolonged, and its end 148 PRACTICAL TELEPHONE HANDBOOK projects into a recess in a. The coil, o, of this combinationoccupies the place of the drop in an ordinary system. Itsarmature, A, is furnished with a long lever, d, on the end ofwhich is a detent which retains A7 in its place. On a beingattracted, D is raised, a is released, and, falling forwardagainst P, has sufficient weight to lift up the latter, and so
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Keywords: ., bookcentury1900, bookdecade1900, booksubjecttelephone, bookyear19
