Typical example of the tadpole detected at the radio frequency 1800 MHz in the interval T (see Fig. 1). Upper panel shows original time series (2003 August 5 event). Middle panel shows its wavelet power spectrum with the tadpole pattern (characteristic period P = 6.3 s) outlined by a contour at the 99% confidence level. Bottom panel shows the global wavelet spectrum (black line) with the maximum for the period P = 6.3 s. The gray line means the 99% significance level.