Line Tuning Equipment Used With Coaxial Cable for Carrier Current Installation on Power Lines

The tests providing the basis of this paper were performed in an effort to determine the best type of carrier by-pass to use on our line between Beaumont, Tex. and Baton Rouge, La. An effort was made to determine how much line tuning equipment was required for various installations. The tests were also made to eliminate considerable field work in making adjustments. Upon the basis of our tests we have decided to use type A carrier by-pass circuits in phase ``A´´ of our line for our communication circuit between Beaumont and Baton Rouge. This carrier will operate on two frequencies of 51 and 68 kilocycles over a 132-kv line through coupling capacitors of 0.0015 microfarad. A reference to comments under type B circuits or to curves Figures 11 and 13 will indicate that type B circuit should not be used for this application. We have, however, decided to use type C by-pass as shown in Figure 8 for the transmission of telemetering carrier signals over the ``C´´ phase of the same 132-kv line. These carrier channels are in the 30-to 34-kilocycle band. The required tuning inductances will be located in the same cabinet as the equipment for the type A circuit.