Development and Manufacture of Electroformed Conductor for Telephone Drop Wire

Abstract

Telephone drop wire is that familiar black overhead wire which brings the telephone service to the home. It is a parallel pair of conductors separated and positioned in an extruded insulation, covered by a cotton serving and jacketed with a neoprene compound of tire tread-like qualities. In the past, a cast copper jacketed steel ingot, rolled and drawn to size, has been used to provide a wire that combines high strength and good conductivity. In order to assure more than a single source of supply and to provide improved mechanical and electrical characteristics, a completely new plant has been constructed for continuous plating of steel wire at completed size. This process provides a stronger, yet smaller and, therefore, less costly wire than was possible previously. Plating is done at 100 feet per minute on 25 wires simultaneously. The conductor is then processed as formerly to provide the neoprene jacketed drop wire.