Section of the model grid for lowest mass of the grid (M_WD = 0.4M_⊙). The deviation of the TESS data intensity I_data to the model I_model as function of the phase is shown. The columns are for constant radius of the donor star (from left to right) are: 1.000, 0.955, 0.910, 0.865, and 0.820 times of the Roche lobe radius, R_Roche. Along the rows, the system inclination, i, varies from 28° to 52° in steps of 4°. The compact companion luminosity was varied each time to fit the system amplitude (see Sect. 3).