Many of us use crossed Yagi antennas with switchable H and V linear polarization. Since the polarization plane of the received signal is usually twisted due to the spatial angle and Faraday rotation, strong stations can usually be received by both H and V antennas with different strengths. Excel spread sheet - see link, allows to calculate the polarization plane twist angles and the resulting losses to orthogonal polarizations from the signal level values given by WSJT-X. The polarization planes determined in this way are in principle two, but the losses are the same in both cases. If we have a rotary feed at higher microwave bands (e.g., 10 GHz, where F. rotation is negligible) can measure V and H polarizations and the angles should correspond to the WSJT-X Dpol data.