A frequency translating repeater (200) for use in a time division duplex radio protocol communications system includes an automatic gain control feature. Detection is performed by comparators (401, 411) ADCs (402, 412); DACs (404, 414) and a processor (315). Detection can be overridden by processor (315) using logic elements (406, 416, 407, and 417) to control the generation of a Channel A/Channel B signal and a PA_ON signal for controlling a power amplifier associated with the transmitter.