Miller, Kempster Blanchard, 1870-1933 · New York : McGraw publishing company · leaf 380
manner similar to that described for the busyback jack. The dont answer jack is used by the trunk operatorif the subscriber whom she has been calling does not respond. Byplacing the trunk plug into this jack a tone different from the busyback tone is put on the line, and the calling supervisory… … FIG. 2SG.—WESTERN ELECTRIC TRUNK CIRCUIT. The standard trunk circuit of the Western Electric Company,used in connection with the subscribers line and cord circuits,shown in Figs. 264, 265 and 266, is shown in Fig. 286. In this theoutgoing end is shown at the left of the figure, the apparatus…
Telephone
Internet Archive · Cornell University Library · Public Domain Mark 1.0. Free to use for anything.
![An illustration from [Electric engineering.] (1902)](https://img.insideoutlibrary.com/img/200/ia-electricengineer03inte-105-44.webp)
