Abstract: A radio interference locator includes a detector circuit having a directional antenna defining a boresight along which electromagnetic radiation is preferentially accepted. The antenna is coupled to a signal detector which generates an electrical signal from a selected radio-frequency (RF) spectral band of the electromagnetic radiation accepted by the antenna. A processor determines the boresight direction at prescribed sample times as well as an associated signal characteristic, such as a signal level of the electrical signal, measured at the sample times. Data are presented that indicate the signal characteristic for the associated boresight direction at each of the sample times. A mobile platform connects the detector circuit and the processor so that they can be freely oriented in space in fixed mechanical formation by a single human operator.