In this paper, we report a simple and inexpensive method for testing the photovoltaic characteristics of organic devices. We report measurement data on P3HT–PCBM organic solar cells spin-coated from chloroform solutions, obtained using a Gallium–Indium eutectic top contact, and a halogen light source. We propose a method to correct the spectral mismatch of this light source with the solar spectrum. The effect of annealing and changing the P3HT:PCBM ratio are studied, and similar results as with evaporated aluminum are obtained. We conclude that Ga–In eutectic and halogen light source can conveniently be used instead of evaporated aluminum and a solar simulator for the study of polymer–fullerene bulk-heterojunction devices.