Abstract: Systems and methods are disclosed for providing calibration of the phase relationships of signals simulcast from a transmission system. In a preferred embodiment, a calibration signal is introduced into the transmission system and provided to various antenna elements. Samples of the calibration signal are taken at a point very near the antenna elements so as to sample phase shifts introduced by the transmission system. The signals of sets of the antenna elements are combined after sampling for transmission down the antenna mast to the active circuitry of the present invention. Accordingly, the present invention operates to selectively energize antenna elements of the sets so as to provide a single calibration signal down the combined signal path. Through reference to sampled signals one at a time, the present invention determines a necessary phase adjustment to result in the desired phase relationship of the signals at the antenna elements.