First two panels: Wavelet-filtered large (first panel) and small scale (second) temperature sky map within the conservative footprint (CF) and averaged along all frequencies; i.e. the sum of the two maps above gives precisely the original one (within the cyan contour) in Fig. 1. Third panel: Spherically averaged power spectra of the cubes (large scale in solid blue, small in dashed orange) normalised by the variance of each cube. With a green dotted line, we plot the damping term of the telescope beam (refer to the y-axis at the right of the panel). Bottom panels: Cylindrical power spectra of the large (left panel) and small-scale cubes (right). Since the wavelet filtering is performed in the angular direction, the difference among the resulting cubes is mostly visible along k_⊥ (x-axis). The beam suppression also acts in this direction: we plot its expected damping term with iso-contour solid lines corresponding to 50, 20, and 5% suppression, from left toright.