An experimental technique is developed to measure the modification of an electric field in a turbulent plasma. The method is suitable for use up to near critical density of the plasma. Measurements have been performed under three plasma conditions, namely, underdense, intermediate density, and near critical density. The results show more rapid attenuation of the coherent wave than predicted by exponential decrease, which is attributed to refraction in our nonuniform plasma column. The data indicate an initial buildup of the incoherent wave (both direct and cross-polarized components) and then a decrease to a certain level depending on the equivalent thickness as the wave penetrates into the plasma.