[en] Calculation of magnetization curves as well as actual and false low-frequency susceptibility for HFSC-films, located in cross-sectional magnetic field is carried out in the Bin critical state model. It is shown that value of losses as amplitude function of variable field has the maximum, the position of which makes it possible to determine the density of J_c film critical current. The position of this maximum, i.e. penetration field H*, is determined basically by the b-film thickness, but not by its diameter, in contrast to the case with long cylinder. Comparison of calculation curves with experimental data indicated good agreement for variable field frequences below 3-5 kHz, which interpreted as manifestation of magnetic field thermoactivated migration