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We find the central stars of the planetary nebulae (PNe) HaTr 7 and ESO 330-9to be close binary systems. Both have orbital periods of less than half a dayand contain an irradiated cool companion to the hot central star. We providelight curves, spectra, radial velocity curves, orbital periods, and binarymodeling results for both systems. The binary modeling leads to systemparameters, or ranges of allowed parameters for each system. We find that forthe CS of HaTr 7 we need to use limb-darkening values for the cool companionthat are different than the expected values for an isolated star. We also fitthe central star spectrum to determine $\log g$ and temperature valuesindependent of the binary modeling. For ESO 330-9 we find that based on ourbinary modeling the hot central star is most likely a post-RGB star with a massof around 0.4 M$_\odot$. We discuss our derived stellar and nebular parametersin the broader context of close binary central stars and their surrounding PNe.We also discuss the present status of known or suspected post-RGB stars in PNe.

Binary Central Stars of Planetary Nebulae Discovered Through Photometric Variability V: The Central Stars of HaTr 7 and ESO 330-9