Transmitter antennas, for VHF and higher frequencies are usually installed in hill-tops and mountain-tops to improve coverage. These sites tend to be windy and thus are favorable locations for wind turbine generators, particuarly if alone or in very small wind farms. Modern turbine generators make use of large solid metallic pylons which, if located too close to the antennas, will cause severe modifications to the antenna radiation pattern and thus to the quality of service. Using WIPL-D we have modeled a typical antenna and a wind turbine at 100 MHz in order to provide criteria for co-siting. The increase in the number of unknowns with increasing operating frequency prevented the analysis to be extended to the GSM band - 900 MHz -. An alternative formulation based on the Kirchhoff-Huygens vector formulas was used to cover from 100 MHz to 1000 MHz, enabling both to confirm the previous results and to extend them.