Systems and methods for sharing an AGC loop between a wireless data demodulator and a spectrum analysis module that operates simultaneously with the data demodulator. In one embodiment, a predetermined hold time prevents the AGC loop from changing gain too often, thereby allowing the spectrum analysis module to collect reliable data. In another embodiment, the hold time may be extended to coincide with a spectrum analysis event, such as a boundary of an FFT block. In still another embodiment, an FFT valid signal is provided such that collected FFT blocks can be designated as suspect and then subsequently processed accordingly.