If you have a need for speed, a radar detector is likely something you’ll find useful. Let’s not sugar coat it though. The purpose of a radar detector, regardless of the manufacturer’s claims, is to protect you from getting a deserved or undeserved speeding ticket, by a police officer using a radar gun. Today’s models combine simple, ergonomic design with up-to-the-minute technology, such as GPS, Bluetooth compatibility, and smartphone integration.
How Radar Detectors Work
Police laser guns transmit a beam of infrared light at a wavelength of 904nm. This invisible light beam is 18 inches wide at 500 feet and then gets smaller and smaller as you approach the officer. When a police officer uses laser they aim this narrow light beam at a reflective area on your car like your headlamps or front license plate. Radar detectors pick up on this signal and alert you via sound, lights, or a combination of both.
Another way to think of it as if police radar gun ‘see’ your vehicle by transmitting a microwave pulse. Then they make use of the doppler effect meaning the frequency of the transmitted pulse is compared to the frequency of the reflection, and speed is calculated by using the difference between them.
Radar Detector are Not Cop Car Detectors
It’s important to keep your expectations reasonable when you go to buy one. A radar detector is designed to alert you to radar and laser signals it receives. Most patrol cars do not have radar guns installed in them unless they are assigned to traffic duty. Also, if the officer does have a radar gun, it may not be turned on. Your radar detector will not protect you from speeding repercussion in these situations.
Types of Radar Detectors
There are three types of radar detector: corded, cordless, and remote-mount.
- Corded detectors usually mount on your windshield using suction cups and generally provide the best range of detection.
- Cordless detectors are transported easily between vehicles, and provide a cleaner installation than corded models.
- Remote-mount detectors are permanently mounted to your vehicle. They provide a clean installation that’s virtually undetectable by thieves.
Understanding Radar or Laser Bands
In North America there are only three radar bands and one laser band police use in traffic enforcement:
- X Band
This is the oldest radar band, used by police in N. J. several locations in Ohio, South Dakota (Mount Rushmore) and in Mississippi. Chances are, unless you are in one of those states, you can ignore this alert. False alerts on this band are high to extreme (depending upon detector model and driving location)
- K Band
Thirty percent of the radar guns manufactured today use this band. False alerts on this band are moderate.
- KA Band
Seventy percent of the radar guns manufactured today use this band. False alerts are low to moderate.
Lasers are growing in popularity with police departments nationwide. False alerts are low. When false alerts are encountered, normally they are reflection of bright sunlight, or wind shear monitors at airports or weather stations
Radar Detector Features
These are generally voice or visual. A voice alert tells you what your radar detector has picked up so you don’t have to take your eyes off the road to look at the detector’s display. Visual alerts such as flashing lights let you know a signal has been detected. They’re preferred if you want to keep your detector quiet for certain driving conditions, such as if you have sleeping passengers.
- “Instant-On” Protection
Instant-On radars are basically the hardest police lasers to protect yourself from. If an instant-on radar is aimed at you, your speed will be measured by the time your detector gives an alert. However, if the radar was targeted on a car ahead of you, a detector with sensitive K-band reception will alert you.
Built-in GPS gives you more functionality. One of the greatest advantages is that they can be programmed to “remember” areas that you drive past and alert you the next time you’re approaching that area.
- Smartphone Compatibility
Most new radar models will have some sort of smartphone compatibility, which you usually setup using Bluetooth and can often transmit alerts directly to your smartphone. These models often act as social aids allowing those that use them to mark enforcement area locations to provide alerts for other drivers in the vicinity.
Legalities and Radar Detection Detection
No that’s not a typo – Radar Detection Detection is a real thing. Basically in some localities, it’s illegal to use a radar detector, and many areas have regulations against using detectors in commercial vehicles. To further enforce regulations, police have developed “radar detector detectors,” often abbreviated to RDD.
These devices pick up oscillations emitted by the receivers in radar detectors, and inform police that a radar detector is being used. Luckily many detector manufacturers now have models that are specially shielded to eliminate most of these emissions, or will shut down when they detect a RDD system in use.