RF interference takes many forms. In this application note we discuss how to detect and eliminate, or at least reduce, interference caused by discrete emitters. These emitters may be devices intended to be transmitters or they may be devices that due to design flaws or malfunctions are radiating signals where they shouldn’t be. We will also discuss interference caused by intermodulation. We specifically do not discuss power line interference, which is too broad a topic to be given proper treatment here. Interference can occur at any frequency from below the AM broadcast band to microwave link frequencies and beyond.