Unmanned Aerial Systems (UASs) are increasingly being used for different applications, opening new opportunities for innovation and research. By means of electromagnetic measurements carried out from UASs, spurious radiations can indicate problems in large electrical or transmitting facilities. Similarly, it is also possible for swiftly detecting and tracking illegal ground transmissions. This paper discusses aspects of electromagnetic compatibility (EMC) and functionality linked with the integration and use of electromagnetic measuring equipment in UASs. Measurements are presented regarding the emission of possible payload equipment and the influence of the UAS operation on the measuring capabilities of the equipment. Finally, considerations on the certification are made.