In one embodiment of the present invention, a probe for measuring an electrical field is disclosed, including at least one antenna, a detection circuit for each antenna, which detection circuit is connected to the corresponding antenna for detecting an RF signal, and a housing in which is received a processing circuit for processing a detected signal, wherein the housing is conductive and includes at least partially a substantially spherical surface for the purpose of forming a ground plane for the at least one antenna, wherein the detection circuit is arranged outside the housing and is coupled to the processing circuit via a feedthrough capacitor with a feedthrough terminal and a shield, wherein the feedthrough terminal connects the detection circuit conductively to the processing circuit and the shield is connected conductively to the conductive surface of the housing.