Examples of PDSs. The black points represent PDSs with n_d = 10 and black circles are for n_d = 5. First (left) panel: IPs with a strong spin frequency affecting the PDS. Second panel: Example of PDSs dominated by white noise. Third panel: Example of PDSs dominated by red noise. Fourth (right) panel: Examples of PDSs of MV Lyr with broken power law fits. The upper PDS shows the case in which the fitting process did not converge on the broken power law shape. There is no f_b but a straight line instead. The middle two cases represent a possible positive detection but with an f_b error larger than 0.10. Apparently, the f_b is not clear even if the fit converges. The lower case is an example of a positive detection with a small-enough error of the f_b due to the clear broken power law shape of the PDS. Individual PDSs are offset vertically for better visualisation.