Thus, to obtain the mean phase profile in the case, when the bin boundary lays in the output record time interval, we add to the summing up counts in each bin the mean count in given output record with the weight proportional to the time of that part of record.

The unavoidable features of frequency spectra in the range of small periods several times greater than the time between the points of time series ($\Delta t$) is caused by the Naykvest noise number of narrow peaks with periods $\Delta t \cdot(n+1/2)$, $\Delta t \cdot(n+1/3)$, $\Delta t 
\cdot(n+2/3)$, $\Delta t \cdot(n+1/4)$, …where n is integer ($n = 5, 6, ...$). The nature of these peaks is connected with the averaging technique by the mean phase profile construction. Such peaks were excluded from the frequency spectra under their consideration. All frequency spectrum points corresponding to the periods in the limits $\pm0.01 \cdot\Delta t$ from the periods multiple to $\Delta t, \Delta t \cdot1/2, \Delta t \cdot 1/3, \Delta t \cdot 1/4$ were also excluded. The total length of the all excluded parts of frequency spectrum is negligible.

Another background peak series appear on the frequency spectra because of the spacecraft rotation. In 