of 31 GHz map one may find for $l=13$ the power is greater than predicted from (\[sp\_noise\]). The power excess is 3.4$\sigma_{l=13}$, where predicted multipole power variation $\sigma_l$ is calculated basing on the model and on the degrees of freedom for the analyzed component. Further we use a censoring of the data to exclude this and similar components from the analysis.

The noise spectral component with $l=25$ has anomalous high correlation between 31 and 53 GHz maps. After subtracting the Galaxy radiation the excess power is 3.3$\sigma_{l=25}$. Components with $l=25$ were excluded from the analysis too.

We find a significant power excess of several noise components on 53 GHz map. We exclude the components with power excess more than 3$\sigma_{l}$. After that we determine the spectrum parameters for the rest components and the procedure is repeated until the spectrum is free from the abnormal components. Thus we excluded the components with $l=7,\, 23,\, 9$ having the initial power excess of 3.11$\sigma_{l=7}$, 2.63$\sigma_{l=23}$, and 2.31$\sigma_{l=9}$.

In the final analysis we use spectral components from $l_{min}=2$ to $l_{max}=22$, except components $l=7,\, 9,\, 13$.

Such censoring effects only a weak power spectrum distortion if the signal amplitude distribution is normal. The matter is 