We report here some experimental results on surface‐wave convolution in a structure of Si on LiNbO3or of CdS on PZT. The semiconductor plate is dc biased. Convolved signals at both the sum and difference frequencies have been observed from the terminals attached to the semiconductor. A simple expression is obtained on the convolved signal amplitude vs the difference in wave vectors of the two input signals. The experiment is in general agreement with the theory. A series of pictures on the convolved signal as a function of the applied dc field is presented.