What makes radar detectors go off

Since this topic is one that we get asked about often, we have broken down the three most common scenarios where a properly working radar detector may not go off when you expect it to. One thing to realize about police officers is that they are humans just like us! Sometimes while sitting in their car at a speed trap they are talking on the phone, doing paperwork, or perhaps even slacking off and watching a TV show on their laptop.

This one is actually really nice! You probably are familiar with those speed signs that are mounted on the side of the road and flash your speed when you drive by. Older radar detectors that do not have very advanced false-alert filtering capabilities commonly alert to these speed signs, usually on K band.

Since these speed signs are used simply for deterrence, not for ticket issuance, technically they are false alerts that annoy drivers. Some Radenso radar detectors are advanced enough that they can recognize the difference between radar signals emitted by these signs and those that are emitted by real police guns. For example, some speed signs use something called modulated radar that looks very different from continuous wave radar that police use.

Other times, the speed signs might use continuous wave radar that is at a different frequency due to either design or frequency drift from poor maintenance than real police radar.

Since the detector knows these are not a threat, it will not alert and you can enjoy your drive with silence. Radar is just one type of speed enforcement tool that police officers use.

Laser, or LIDAR, is a type of speed measurement that focuses on one particular car instead of a wide swath of the road. Since it operates based on a narrow laser beam you can think of it kind of like a laser pointer , police officers have the ability to target a specific point on your car such as a license plate or headlight. While sometimes radar detectors which often have laser sensors built in as well can pick up a LIDAR beam that is aimed at the car, it is also normal for the sensor to miss the laser shot completely since the beam is too small.

To get true protection from laser, we do not recommend relying on a radar detector from any brand including ours. Instead, consider a laser jammer for complete protection.

In conclusion, there are several reasons your radar detector may not alert when you expect it to. While the app is proprietary, unlike Valentine's open API implementation, it does allow you to tap into the hivemind of Escort and Cobra radar users. You can be alerted of speed traps and other threats in real-time while they are still outside of detection range. And when you're connected to the app the current speed limit is displayed on the Redline's screen next to your actual speed, allowing for customizable overspeed alerts.

In our testing, the app integration was perhaps the only major weakness of the Escort Redline c. It would occasionally disconnect from Bluetooth, requiring a reboot of the app. Also, the speed limit information was frequently inaccurate with Waze doing a much better job of displaying the correct limits.

Nevertheless, if you've got the money for it, this radar detector is the full package and absolutely the one I'd choose. If you have less to spend but still want best-in-class performance, the Uniden R3 is Roadshow's detector of choice. Sharing many of the same internals as the runner-up pick, the R3 was Uniden's top performer before the R7 showed up, and it remains an impressive package. The biggest differences from this unit's big brother are a lack of directional guidance and a less-robust, if still impressive, detection range.

As to the latter, the R3 still beats some competitors sold for nearly twice the price including big hitters from Radenso and Escort. The absence of directional arrows is not surprising in this price class, and certainly not a dealbreaker.

GPS is also built into this unit and enables speed camera alerts, low-speed muting as well as the capability to set up to manual lockouts by double-pressing the Mute button.

Speaking of controls, this detector is on a short list of window-mounted devices that assign front-facing real estate to frequently used buttons instead of banishing them to the "fumble zone" at the top of the unit, out of sight. That's a personal pet peeve, but still, kudos to Uniden for positioning the Mute and Mark buttons where they can be easily accessed.

And now for something completely… familiar. At the risk of being repetitive, the best budget radar detector available today is yet another offering from the folks at Uniden. The DFR7 initially went on sale in , and despite repeated price drops, it continues to receive firmware updates from Uniden and remains a strong performer, even when pitted against some of the best detectors on the market.

GPS is built into this unit and provides the benefits of low-speed muting to reduce false alerts as well as manual marking of up to lockouts and speed camera alerts. Information is displayed on a monochrome OLED display and voice alerts are available as well. By all accounts, false alert filtering in the Uniden DFR7 is excellent, and will keep the detector from alarming every time a blind spot monitoring system is in the vicinity.

Radar detection range is impressive as well and performs especially well on the For drivers on a razor-thin budget, we present the Whistler ZR Plus, a radar detector which may provide some helpful situational awareness, as long as you're mindful of its limitations.

Radar and laser detection are both on the menu, and the unit displays alerts on a green OLED readout. Voice alerts are optional in both English and Spanish. Filter modes are manually selectable via the City button, which cycles between Highway, City, City 1 and City 2.

GPS is absent here, which means custom location alerts and low-speed muting are unavailable. Detection range isn't impressive, and it was chatty in our testing, with several false alerts from surrounding vehicles and traffic sensors sneaking past the filters.

It definitely alerted me to legitimate threats, and if you can get past the Boy Who Cried Wolf syndrome, it may be worth your money. Still, our recommendation, based on experience and expert advice, is to save up your dollars for a detector with a few more features.

If you're new to the world of radar detectors and don't want to invest a lot of money or time in learning new terms and technology, we think Cobra's RAD i may be the place to start. However, it does have one feature which puts it over the top: Bluetooth app integration. At the risk of oversimplification, the i can be thought of as "Waze Plus.

Once you start running your new Cobra radar detector, you're immediately granted access to the free iRadar app, available on iOS and Android.

The software is essentially the same as the separate Escort Live app accessible by owners of pricier, more precision hardware, as both brands are manufactured by Cedar Electronics. You can even sign into both apps with the same account credentials, as we did in our testing. Since , these two apps have shared their alert databases. This means, as a Cobra user, you're getting the benefit of data in the cloud from drivers with more-powerful Escort detectors.

The iRadar app itself is colorful and intuitive to use. While the RAD i may not have built-in GPS or the best detection range, the app fills in a lot of holes with warnings of upcoming speed traps, speed cameras and more without needing to understand more technical terminology.

Cobra users can also report their own police sightings by holding down the physical Mark button on the unit for 2 seconds. Outside of app integration, the Cobra RAD i is similarly easy to set up and use with a simple, black and white display and all the familiar buttons.

As this model consists of hardware on the more inexpensive end of the spectrum, expect more false alerts and missed hits. Still, we think this is a good option to consider if money is a major limitation. Many of the options on our list can be discreetly hardwired into your vehicle's electrical system, but if a box mounted to the windshield, sun visor or rearview mirror just won't work for you, it's time to step up to a custom install, otherwise known as a remote radar detector.

No matter which solution, you'll be paying a premium, not to mention the cost of installation. If you're going to take the plunge, we think the Escort Max Ci is worth your coin.

If you liked the sound of our splurge pick, the Redline c, then the Max Ci will be similarly appealing. Once installed, this aftermarket solution integrates GPS, a front radar receiver, as well as display and control modules, which allow you to interface with the system. Additionally, Bluetooth allows the system to integrate with the Escort Live app on your phone. For additional cost, the system can be expanded to include a rear radar receiver, which enables directional indicators, as well as front and rear sets of laser jammers.

The main advantage of a remote radar detector is superior aesthetics, and the Max Ci is an attractive package paired with Escort's best technology. Radar detectors are still effective, as they continue to be widely used across the country, but if your goal is to build an almost foolproof system, it's time to consider adding laser jammers to the mix.

ALP requires a custom installation, as all laser jammers do, with at least two sensors up front to detect and fire back a jamming signal at police radar. The system is expandable, maxing out at six sensors, split between front and rear, for necessary coverage, depending on the size of the vehicle. Bluetooth and Hi-Fi modules are optional for audible alerts, and AL also sells a radar antenna that can be added into the mix if you don't want to run a separate unit from another manufacturer.

As laser jammers aren't legal in all 50 states, the AL Priority is sold as a "parking system," and it can be used as such, should you find yourself in a locale where the laser defense abilities need to be disabled. Perhaps not surprisingly, user reviews indicate the parking feature is not where the system shines. In the search for the best radar detector for motorcycles, one answer came up over and over: the best radar detector for your bike is the one you'd use in your car. The Valentine One and Escort Redline c are both strong performers.

So, the question becomes, how do you mod the detector for your motorcycle? Designed to work as part of Ram's ball-and-socket mounting system, the Power Plate consists of an adhesive metal plate, which attaches to any flat-bottomed radar detector, and a rubber cradle with two rare-earth magnets. Once paired, the plate holds the device securely, only letting go when the detector is rotated 90 degrees relative to the Power Plate. Every radar detector motorcycle set-up is going to be different, but I think this is one component that will work well for most riders.

Let's be clear: Yes, radar detectors are about situational awareness, but they're about one very particular type of awareness, spotting the police before they spot you.

So, it's natural to ask if such a subversion of authority is legal. For commercial drivers, federal law prohibits the use of detectors in vehicles in excess of 10, pounds.

However, state laws vary, so check the particulars of the states you'll be driving through. In Illinois, New York and New Jersey, radar detectors are prohibited in all commercial vehicles, regardless of weight. While radar detectors are legal for most passenger vehicles, some states do have laws restricting windshield mounts.

In California and Minnesota in particular, it is illegal to mount anything to the windshield that might obstruct your view. While these laws aren't always strictly enforced, you may consider exploring visor-mount options or one of several accessories allowing detectors to mount to your rearview mirror. One type of electronic device that's illegal in every state by federal mandate is a radar jammer. On the other hand, laser jammers are not illegal… at least not everywhere.

If you're reading this, you probably already know whether you're the kind of driver who would be well-suited to operating a radar detector. Still, it's useful to dispense with the notion that radar detectors are just for speed demons.

From this point, you need to decide how much of a power user you are. We've found you'll get a plug-and-play experience from the Cobra RAD i, a user-friendly radar detector with expanded capabilities provided via its smartphone integration. Similarly, you'll get a great out-of-the-box experience from Escort's Redline c, but the gulf between these two detectors' feature sets and prices is enormous. So, usability is just one consideration. Deciding what you can afford, and what features are worth the cost is key.

Starting at the low end of the radar detector price scale, you immediately come up against a challenge. Is a detector worth buying at all if you don't have the money to invest in a product with at least mid-level quality and reliable product support?

Bravy would argue there's a point of diminishing returns. While there's an ultra-low budget option on our list, it's worth asking yourself if you have the fortitude to deal with the sub-par range and false alarms that lower-tier hardware delivers.

In our testing, such units became more frustrating than useful. Given the choice, I'd suggest opting for a free app like Waze and save your pennies for quality mid-tier equipment. We consistently ran Waze alongside our detectors, and it frequently identified speed traps that didn't set off alarms on our detectors and vice versa.

Differences between mid-tier and top-tier radar detectors are less pronounced. Pricier models will get you niceties like directional arrows, which help you locate the source of radar signals. Bluetooth, Wi-Fi and MultiRadar detection are also generally only found in higher-end units. Whether you shop in a brick-and-mortar store or online, you're going to see long, bulleted lists that contain a dizzying array of features. Here are the things to actually pay attention to, according to our radar detector experts.

Sherbondy concurs, "If you're looking at higher end detectors, try selecting one with the best possible detection range and false alert filtering and that can be updated over time. The longer the detection range, the more time you have to safely react to a hidden officer, and if you have good false alert filtering on your side, you can be sure you're not riding the brakes for nothing. Those are also emitting radar," according to Bravy.

Additionally, to take false filtering to the next level, GPS should definitely be on your wish list. In addition to auto or manual lockouts, GPS enables low-speed muting, which means less physical toggling between Highway and City modes to silence falsing from automatic store doors and roadside speed signs.

As you've seen, the recipe for a good detector comes down to a handful of qualities and features. Yet, one of the boxes our tester units came in was swathed in a list of marketing claims 29 items long, the first of them being "Maximum Performance.

So, if radar signals are not coming from a police officer, where are they coming from? There are two types of false alerts, stationary false alerts and moving false alerts. Stationary false alerts have been around for just as long as radar detectors have.

These are radar signatures that are emitted from non-moving locations, most commonly automatic door openers for stores. These alerts are especially annoying to people that drive on a regular commute past them, or that live near these false alerts. Another type of very common stationary false alert is from orange construction signs that can display digital messages on them; even though you cannot visually see a radar gun, they usually emit on K and sometimes KA band.

These false alerts are usually detected as a strong, stable, continuous radar alert. One particularly nasty type of stationary false alert is emitted from traffic speed sensor systems that are installed to monitor the speed and congestion of traffic. Unlike false alerts emitted by most stationary sources, these are short-duration yet high-intensity bursts of radar. They might cause your radar detector to alert full-strength for half a second, but then vanish — only to repeat this cycle hundreds of times over the course of a long highway drive.

As population density and commercial development has increased over the past few decades, stationary false alerts have become a larger problem. It is not uncommon for radar detectors to pick up five or six simultaneous false alerts when driving through a strip mall or business park. A relatively newer type of false alerts are those that originate from moving vehicles.

These are exclusively a result of more advanced safety systems that manufacturers put in newer cars. These systems include blind spot monitoring systems, radar cruise control, and emergency collision avoidance systems.

Since most of these systems work based on distance and speed information, the car manufacturers have decided to implement radar emitters to provide that information. Moving false alerts are a newer problem that was never an issue until the last several years.

Older cars had none of these safety systems implemented, so there was no radar pollution caused by them. False alerts emitted by moving vehicles present very differently than those originating from a stationary source like an automatic door opener.

Moving false alerts can be difficult to identify, as their signal strength will change constantly based on the distance between your car and the offending car, traffic conditions, and other factors. What is frustrating about moving false alerts is that they seem just like a real police officer is following you with his radar gun left on.

How can you know if it is a real police officer or a false alert? There is no definitive way to know for certain, which is why it is so critical that the detector you purchase has the ability to filter out as many of these as possible. At Radenso, we believe false alerts are the 1 reason that people become frustrated with radar detectors.

Due to that, we are committed to designing a hardware platform that is modern, sophisticated, and equipped with the necessary tools to deal with false alerts. The addition of a GPS chipset to radar detectors is one of the best things that has happened to combat stationary false alerts. In terms of false alert elimination, GPS is used for two things — lockouts and speed based muting. GPS lockouts work based on a simple concept. Since the radar detector has a GPS chipset in it, it knows its exact location at all times.

The detector stores this information in memory, so the next time you drive by the same location it remembers it is a false alert. With auto-lockouts, if you drive by a police officer in the same location two or three times, your detector will think that it is a false alert and not warn you!

We take a different approach — we know you are intelligent enough to determine a real or a false alert.