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We investigated whether the predictions and results of Stanishev et al (2002)concerning a possible relationship between eclipse depths in PX And and itsretrograde disc precession phase, could be confirmed in long term observationsmade by SuperWASP. In addition, two further CVs (DQ Her and V795 Her) in thesame SuperWASP data set were investigated to see whether evidence of superhumpperiods and disc precession periods were present and what other, if any, longterm periods could be detected.  The results of our period and eclipse analysis on PX And confirm that thenegative superhump period is 0.1417 \pm 0.0001d. We find no evidence ofpositive superhumps in our data suggesting that PX And may have been in a lowstate during our observations. We improve on existing estimates of the discprecession period and find it to be 4.43 \pm 0.05d. Our results confirm thepredictions of Stanishev et al (2002). We find that DQ Her does not appear toshow a similar variation for we find no evidence of negative superhumps or of aretrograde disc precession. We also find no evidence of positive superhumps orof a prograde disc precession and we attribute the lack of positive superhumpsin DQ Her to be due to the high mass ratio of this CV. We do however findevidence for a modulation of the eclipse depth over a period of 100 days whichmay be linked with solar-type magnetic cycles which give rise to long termphotometric variations. The periodogram analysis for V795 Her detected thelikely positive superhump period 0.1165d, however, neither the 0.10826d orbitalperiod or the prograde 1.53d disc precession period were seen. Here though wehave found a variation in the periodogram power function at the positivesuperhump period, over a period of at least 120 days.

SuperWASP observations of long timescale photometric variations in cataclysmic variables