Example of a 2D (spin longitude vs. pulse number) FFT spectrum featuring the Tb mode of session L102418 (left) and the Tq mode of session 150518 (right). The Fourier transform was taken from the region enclosed in the blue rectangle in the left-side pulse sequence plot. Frequencies close to zero were eliminated from the analysis to reduce the influence of red noise on the peak-finding algorithm. The color-bar range in each figure is set by the local minimum and maximum and is not uniform across different LRF spectra.