How does a radar detector work?
A detector is a radio receiver tuned to specific frequencies used by police radar. It is extremely sensitive, often able to hear radar from over a mile away, far beyond the range at which radar can clock a vehicle’s speed. In evaluating a detector, the two most important performance criteria are sensitivity and selectivity. Sensitivity is a measure of a units detection range. Selectivity refers to a unit’s ability to reject non-police microwave signals and is an important feature because of the many sources of “electronic pollution”. Note: Automatic door openers and some burglar alarms operate on X-band, which is a police band. A radar detector cannot tell if a store is opening a door or a police officer is checking speed.
