Variations of the O i] 1641 Å line fluxes during quiescent phases of Z And and EG And as a function of the orbital phase according to the ephemeris of Fekel et al. (2000a) and Fekel et al. (2000b), respectively. The light gray belts correspond to the intersection of the H i zone with the line of sight along the orbit (see Sect. 4.3). The dark belt reflects a time interval of the total eclipse of the point source by the giant in EG And (Δφ =  ± 0.038; see Table 1 of Crowley et al. 2008). Fluxes were taken from Figs. 4 and 8 of Shore & Wahlgren (2010).