Radar jammers & radar scramblers - Do they really work? (2024)

Is a radar jammer or radar scrambler really effective at jamming police radar?

Radar jammers & radar scramblers remain some of the most elusive, mysterious, and misunderstood countermeasures ever produced.

We hope to dispel the myths and shed light on the topic with this Radar Jammer & Radar Scrambler Guide.

Updated: 07-01-2024 by Veil Guy

Introduction

Ever since the introduction of police radar speed enforcement, their have been attempts to develop radar jammers to prevent speeds from being obtained as radar detectors are designed to only detect, not interfere with it.

In over the four decades we have been connected to the industry in some form or another, we have only found two radar jammers and for only a short period of time, have actually had some success in jamming police radar.

But, those days a long gone and no viable option exists today.

Wouldn’t it be nice if you were able to own a radar jammer or a radar scrambler to prevent speeding readings?

Sure, but even if they did, you wouldn’t want to assume the risks in using a jammer.

Ostensibly, two forms of jammers exist, one is active an radar jammer and the other is a so-called passive radar jammer or scrambler.

How does an active radar jammer work?

Active radar jammers work on the principle of actively transmitting an interfering signal meant to overwhelm the natural doppler-shifted frequencies returned to the police radar gun, that occur from reflected waves that police RADAR employ to obtain a vehicle’s speed.

They often employ multiple radar antennas for the different police radar band frequencies, to be jammed, and a control module.

The radar jammer antennas are mounted to the outside of the vehicle and connecting cables are typically run through the firewall to the control module located inside the vehicle.

Typically what happened was that when the active jammer was targeted with radar, the jammers would transmit a radar signal themselves back towards the targeting officer.

Other less sophisticated radar jammers would continuously trasmit whether a radar signal was detected or not.

In the latter instance, such jammers would set off everyone’s radar detectors in the area (including your own, if you had one).

Obiously, this was not a good situation and severely diminished the value of using one.

Active radar jammers, when they were available, were priced at greater than $1000 and were extremely difficult to locate and purchase as they were deemed illegal by the FCC.

Their assembly quality was also often called into question and for good reason, as these jammers often originated in someone’s basem*nt.

Are active radar jammers legal to use?

Unlike police laser which can be legally jammed by laser jammers in most states, police radar can not be legally jammed anywhere.

In fact, any attempt to jam radar (whether one is successful or not) violates FCC regulations and is a federal offense (felony).

Radar detectors are a different animal, in that they are designed to only detect and alert to radar and do not attempt to interfere with it and so for the most part, they are legal to use.

Do active radar jammers work today?

While active radar jammers remain illegal, they have also proven to generally not work, especially against the latest digital police radars.

Older analogue jammers did have some jamming effect on older analogue X-band and K-band RADAR but were often bulky, cumbersome to operate, and ran continuously – setting off every radar detector in the immediate vicinity.

Their use ended up adversely effecting drivers in front of you hit their brakes and slow down which presented potential safety problems for drivers who used a an active jammer.

One jammer that also showed some effectiveness was the Scorpion Radar Jammer.

We tested it years ago and found it to be somewhat effective against older X-band and K-band guns.

Scorpion jammers also had the distinction of only transmitting when you were being targeted and was also designed to jam Ka-band radar (a much harder band to do so), but we found that it was largely ineffective at the three primary Ka-band frequencies used by police.

The jammer was also constructed like it was home-made (which it was) and it promptly failed on us completely, the electronics literally went up in smoke.

Furthermore, analogue jammers tend to lose calibration and eventually go out of tune – further diminishing their radar jamming effectiveness over time.

Today, advanced radar guns can indicate to the officer that someone is using a jammer.

They do so easily by monitoring the return frequency of the jammer during the time that the gun doesn’t transmit – a dead giveaway of the user of an active jammer.

In some cases, a jammer may inadvertently produce a higher indicated speed on the officer’s radar gun!

Can you picture trying to explain to a police officer how his 95mph reading of you was introduced by your jammer and not by your actual speed?

At any rate, the technology has progressed today to be primarily digital, which makes them much more accurate, less prone to error, and extremely difficult to jam effectively.

How does a passive radar scrambler claim to work?

Companies that market passive radar scramblers claim that their radar scramblers receive incoming radar and then mix in RF “noise” and reflect back a signal to the police radar gun to supposedly “confuse” it becoming unable to display an accurate speed reading.

At one trade show there was even a demonstration that was performed where a radar antenna was placed directly in front of their device and changing speeds were displayed on the gun’s control unit.

To the novice, this may seem initially convincing however, in reality such demonstrations are meaningless and intentionally misleading.

The reason? At typical targeting distances of hundreds to thousands of feet, the amount of reflection being returned by your vehicle targeting officer far exceeds, by orders of magnitude, the infinitesimally small amount of “modified” signal coming from such a small device mounted on the windshield.

Even if the unit were placed directly by the grill, its output wouldn’t amount to anything in practice.

Do passive radar scramblers work?

Again, so don’t even think about attempting to use a “passive” radar jammer or scrambler as your vehicle’s own reflections will most certainly overwhelm any small “passive jammer/reflector” by several orders of magnitude.

These devices don’t even make good radar and laser detectors!

For years, Radar Roy of RadarBusters offered $50,000 to anyone who could prove any passive radar jammer / scrambler that worked and of course, no one collected!

Are passive radar scramblers legal to use?

Late in 1997, the FCC also ruled that so-called passive-reflector type “radar scramblers” were also illegal to operate whether they are effective or not (they never have been effective) because the FCC considers any attempt as “malicious interference.”

How does a passive laser scrambler claim to work?

The same type of passive scrambling claim is also purported to work as a laser scrambler and again the claim has been and continues to be bogus.

When police laser tests are conducted with the infra-red (IR) photography, any laser scrambler appears only as a little IR flash light.

Not only is it infinitesimally small again, the IR “transponder” or light is solidly lit.

Even if the amount of IR light coming from the unit was bright enough to overwhelm the IR light reflected from the rest of the vehicle such as the headlights and flashlights, to successfully jam police laser requires sophisticated pulsing flashes to interfere with the pulse-rates of police lasers.

A tiny little solidy lit light that barely puts out anything, is absolutely useless.

How do passive laser scramblers work?

They don’t!

There are only two proven police laser countermeasures currently available:

• Active Laser Jammers
• Veil Stealth Coating

Are there any effective countermeasures for beating photo radar enforcement?

While passive “jammers” have never been effective, there are a couple of other passive solutions that can in some cases beat photo enforcement systems.

The first one is a license plate cover that obscures the numbers in the visible spectrum of light.

The newer photo systems use infrared cameras which can be thwarted by an infrared absorbing material to black out the plate.

While your speed will still be measured, identification of your vehicle will be seriously hampered since your license plate is obscured, so there is no way to automatically issue you a citation in the mail.

You can learn more about that approach, here.

Are there any other ways to beat speeding tickets?

An even more ominous threat to the motoring public is currently being used and is much more difficult to detect, the likelihood of successful court challenges to issued tickets is much smaller, and it is now in widespread use.

That technology is called police lidar and it has proven to be a far more lethal speed enforcement tool.

You can learn more about this technology and the ways to reduce your risks to it, here.

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