You’re driving along, enjoying the sunny weather and open road. You look in your rearview mirror and there they are.
Those dreaded red and blue lights. Nothing ruins your day faster than a speeding ticket.
About 41 million tickets get handed out each year. That is 100,000 people each day whose day gets ruined.
It doesn’t have to be this way. Buying a radar detector can help alert and protect you.
how radar detectors work
Before you buy one though, you need to understand how radar detectors work. Use our guide to understand what to look for in your next radar detector.
How Does Police Radar Work?
Police radar detectors use Doppler technology to determine the velocity or speed of your vehicle. The radar is targeted at moving vehicles and a beam is activated.
As the vehicles move away from the radar gun, the radar waves get progressively longer. If the vehicle moves towards the radar gun, each wave gets shorter than the previous.
The change in wavelength is a calculation of the vehicle’s speed. Radar detectors then need to warn you of these waves or interfere with them.
The problem with this method of speed detection is that the radar waves are not pinpointed. When they get sent out they go in many directions.
If there are many cars coming down the road it is difficult to get an accurate reading on one car. This accuracy gets even worse the further the cars are away from the police officer.
How Police Lasers Work
Laser speed detection equipment use an infrared light to point at your specific vehicle. The vehicles around the targeted car wouldn’t detect the laser light.
Laser detection is a vast improvement on radar devices. Driver’s get very little to no warning that their speed is getting measured.
Often radar detectors today won’t pick up on the radar at all. If they do pick up on the laser, it is too late. You now have a warning you will be receiving a ticket.
A police officer will hold the gun up to his face and aim the laser at a reflective spot on a moving car. Then the gun will fire about 200 pulses per second at the car.
It needs about 60 of those pulses returned to get an accurate measurement of the vehicle’s speed. These readings should be a progressive reading of distances such as 100 feet, 95 feet, 90 feet.
What Is a Radar Detector?
These small devices in a vehicle alert you when police are monitoring your speed. Not all radar detectors work the same and not all will alert you to every police speed detection device.
How Radar Detectors Work
Radar detectors alert you to the police radar guns that work on K, X, and Ka-Band radar wavebands.
X Radar Waves
This is the oldest radar technology operating on 10.5ghz. Most urban police departments no longer use X radar.
If you live in a more rural area you will be more likely to find X band getting used. It doesn’t get affected by bad weather, but it is also very easy to detect at far distances.
K Radar Waves
This radar technology was an improvement upon X radar. Police operate on this band between the frequencies of 24.125 and 24.15ghz.
It shortened the distance it can get detected at by radar detectors. Most modern detectors have compensated for this though.
Unfortunately, you can expect a lot of false alerts with this type of radar detection. Other devices like automatic doors also use this frequency. Drive down a street with a lot of gas stations and you’ll get tired of the alerting.
The Ka-Band radar has increased complexity making it better than its predecessors. X and K band operate on one frequency. Ka-Band uses up to 5.
It has the shortest distance for detection. It also has a very low rate of false starts.
A quality modern radar detector will give you protection against this radar. Older or lower quality detectors might fail you in altering though.
The radar detector in your vehicle uses electromagnetic emissions to detect the radar waves. When radar waves get sent out from the police’s device it creates a certain amount of electricity in the air.
The radar detector in your car works like a radio antenna by receiving this energy in the radar wavelengths. It then uses this energy to convert it into an alert for you.
Useless Against Lasers
You will notice that radar detectors have laser detection abilities. They alert you, but at that point, the laser is already on you and detecting your speed.
It is too late to reduce speed or do anything. If you installed your radar detector in your windshield it may not ever pick up the laser at all.
What About Jammers?
Using a jammer is a way of fighting back against the detector. Instead of simply detecting the signal and alerting you, it sends out its own signal.
A laser jammer will send its own laser pulse back with nonsensical readings. So now the police gun will read 100 feet, 300 feet, 25 feet, 96 feet.
The police gun won’t understand this and won’t be able to create a speed reading. It will continue to fire trying to get data that it understands.
You will need to slow down, turn off the jammer, and allow the police to read your speed. If you don’t do this, you alert the police to the use of your jammer.
Equip and Protect Yourself
Now that you know how radar detectors work, you can read radar detector reviews with purpose. This will help you find the detector that suits your needs.
For the most coverage, you will want to be able to detect all types of radar. Just know that you may get some false alarms from the K band detection.
You now know that while laser detection is helpful, it can’t fully protect you. You’ll want to look for a jammer to protect yourself from laser speed detection.
Use our best radar detector in 2018 buying guide to help you decide.