Radar Detecting
A radar gun uses radar waves to calculate how fast you are speeding. These waves can be detected quite easily by a simple machine that reads these waves. Since radar waves produce electromagnetic energy and radio waves, the radar detector only needs to pick up these waves to work. That means they can use a typical radio receiver such as the one in your car stereo to pick up the signals coming from the radar gun. Whenever the radar detector picks up radio waves, the unit goes off.
Selecting the Frequency
The radar guns used by police emit the same kind of radio waves found everywhere. To be accurate and to prevent them from going off, the radar detectors are designed to search a selected range of frequencies only used by police radar guns. When the radio receiver inside the radar detector finds waves in this frequency range, it will emit a beep and ignore the signals coming from other frequency ranges. More advanced radar detectors allow you to change the frequency that triggers the alarm. Sometimes the radar guns used by law enforcement change the frequencies they use.
Using the Radar Detector
The radar detector sits on your dash and constantly monitors the area in front of your for police radar signals. When it detects them, an alarm is triggered (either a silent alarm or loud noise). The alarm gives you ample time to slow down because it takes several seconds for the police radar gun to zero in on a target. That is because a police radar gun will emit radar waves in all directions over a wide area of the road. Yet, only waves reflected directly back to the gun and its receiver create a reading. As long as the gun is not pointed directly at your speeding car, your detector will sound with plenty of time to hit the brakes.
Tags: police radar, radar detector, radar guns, radar waves, radio waves