Both the power increasing of a television broadcasting channel for the purpose of minimiaing weak signal areas and depressing of radiation pattern to prevent some interference in known quadrants may be needed in TV broadcasting. This study shows that, the two needs mentioned above are solvable by adjusting the phases of feeding points, or redesigning the lengths of feeder lines between transmitter outend and feeder inputs in super gain antenna. A theoretical study on lengths of coaxial cables and a practical procedure of designing cable lengths, which is simple and inexpensive to apply, is presented.