Now im not completely sure how legal this is, or if it even is legal, but my teacher today was talking about a little device someone made for him, that sets off people's radar detectors on the highway, and they slow down. It would be a rather funny prank to pull on someone speeding in a fancy sports car, with their brake lights coming on. Anyways, if you know of a schematic of this, or how to build one let me know, as Ive looked on google, and cant find anything. If it is illegal, well, just let the topic rest. Thanks!