3846638 is referenced by 87 patents and cites 5 patents.

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.

Improved coupling arrangement for power line carrier systems
Application Number
Publication Number
Application Date
September 6, 1973
Publication Date
November 5, 1974
Wetherell Daniel L
General Electric Company
H04m 11/00
H04B 03/56
H04B 03/54
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