The distribution of the periodically variable objects found in the period range from 125 min (7500 s) to 167 min (10 000 s). Note the peaks at periods close to 1/11 d, 1/10 d and 1/9 d which are due to spurious signals caused by systematic noise. Periods within the ranges indicated by the dotted lines were flagged as likely spurious. Note also that contact binaries will typically give signals at half their true orbital period, so the period range here corresponds to contact binary orbital periods from 250 min to 333 min.