of the structure function curve up to 1. All of our observations had less than 5$\%$ pile-up except for PKS 2155-304 Obs. ID 124930301 (6.5$\%$) and both observations of MKN 421 ($\sim 10\%$). Overall, the percentage of pile-up in our sample increases with the number of counts except for NGC 4151 Obs. ID 112830201 which is 5$\%$ piled-up and has an average of only 25 counts.

Results
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### Wavelet Analysis Results {#wavelet_results}

Of the observations that we analyzed, only one showed a quasi-period of interest (at 3.3 ksec), and this occurred in an observation of 3C 273 (ID 126700301). The continuous wavelet transform result for this observation is shown in Figure \[3ccwt\] with the quasi-period circled in the real and power plots (second and third panel, respectively). One can see that the quasi-period appears in the last two-thirds of the observation. In the real plot, the concentrations match up with peaks in the light curve, and the power is concentrated at $4.2\times10^{4}$ s. The wavelet is sampled with 220 dilations ($N_{l}$) ranging between $\sim 207.2$ s and $2.3\times10^{4}$ s. We note that the data in Figure \[3ccwt\] are binned from 5 s to 100 s for clarity and that 