Iron armored aerial communication cable

This paper describes a study of the application of an iron armored aerial communication cable as an inductive coördination measure permitting a high voltage transmission line to occupy jointly for a distance of about 20 miles the same railroad right-of-way with telegraph and telephone circuits. Calculations are given indicating the induction to be expected on open wire communication circuits, and the degree of reduction afforded by several different designs of cables, both armored and non-armored. The effect of cable on the normal operation of the telegraph and telephone circuits carried through it also is considered.