Period search results for 2dFS 936. Left: comparison of the different period search methods. The presence of a signal is marked by a maximum for Fourier and AOV methods, but a minimum for conditional entropy, Renson and Lafler & Kinman methods. Middle: Fourier periodogram for the raw (top) and prewhitened (middle, for the best-fit Fourier period) data of 2dFS 936, along with the spectral window (bottom). Right: photometric variations of 2dFS 936, phased using the best-fit ephemeris (see Table 2). The thick red line corresponds to the best-fit Fourier sinusoid, while the symbols for data are as in Fig. 1.