About 20 years ago, an electrical engineer friend of mine had built himself a small (~10 GHz, IIRC?) transmitter about the size of a garage door opener. It had a single red button on it that, when pressed, emitted a signal in one of the frequency bands that radar detectors picked up.
As a teenager, it was amusing to watch another car go zipping past us on the highway and then see their brake lights come on right after Nathan would hit the button.
As a teenager, it was amusing to watch another car go zipping past us on the highway and then see their brake lights come on right after Nathan would hit the button.