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The dual-channel chopping photometer is a combination of a chopping photometer design (Taylor 1980, PASP, 92, 108) and beam splitting design. The photometer chops between sky and star. The chopped light is then beam-split to two filters and photomultiplier tubes. The choice of the two filters used determines the color index of the star. Since fluxes in each filter are measured simultaneously, the color index is not affected by poor sky transparency. Also, by chopping, the sky background can be readily removed. The photometer is mounted at the Cassegrain focus of the the Southeastern Association for Research in Astronomy (SARA) Observatory 0.9-m telescope at Kitt Peak. The photometer is in routine use with an emphasis on two research programs. One is the measurement of the colors of astrometric reference stars used for spectral type and luminosity classifications. The other program is the measurement of W UMa type eclipsing binary light curves. We will describe the photometer head and hardware and software control of the photometer, and include a brief summary of recently measured light curves of AW UMa. Support for the construction of the photometer from NSF Grant AST-9014296 is gratefully acknowledged. MWC acknowledges the support of the Physics Department at East Tennessee State University. TP acknowledges the support of Allegheny Observatory of the University of Pittsburgh.
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