The practical telephone handbook and guide to the telephonic exchange (1906)
Poole, Joseph · New York, Macmillan Co. · leaf 218
Fig. 217.—Scale & MULTIPLE SWITCH-BOARDS—MAGNETO SERIES 193 board may be looked upon as a collection of Standard boards,with the addition of the multiple-jacks and provision forengaged testing. The indicator drops in connection with the local-jacksare arranged at a lower level, in four groups… … Fig. 218.—Scaled terminated on each section of this board, and whose calls areanswered by the operators attending on this particular section.Between the local-jacks and the drops a ledge or shelf isformed, through holes in which the connecting cords pass,the plugs attached to them resting when not…
Telephone
Internet Archive · Northeastern University Library · Public Domain Mark 1.0. Free to use for anything.
