A power line carrier system is coupled to two or more phase wires of an electrical power transmission line by transformers and coaxial transmission lines. Each phase wire to be used is provided with a coupling capacitor which is respectively coupled to one end of a coaxial line through an impedance matching transformer. The other ends of the coaxial lines are coupled to the carrier system through one or more isolation transformers. Use of this coupling arrangement eliminates the previously used, exposed unbalanced lines, and their inherent disadvantages. Where a plurality of phase wires are used, this arrangement permits the carrier to be coupled to the phase wires with various relative voltage magnitudes and various relative phases.