Laser Jammers Tested

Which jammer best protects against a laser ambush?

By Radartest staff
Test date: 2010

Note: These products have been discontinued. See the most recent laser jammer test.

Chrylser 300C viewed through laser gun HUD

The laser jammer occupies a niche market and is probably never destined to become a mainstream product. Some states ban the device and even where it's legal, major manufacturers are nervous about being seen as purveyors of a gadget whose sole function is to circumvent police laser guns.

This status as a cottage industry has naturally limited the proliferation of laser jammer models. At the time of our 2005 laser jammer test, five manufacturers offered as many models. Today, two of those have since folded their tents, leaving only three veteran manufacturers still in the game.

One of those, K40, continues to sell the Defuser EX, usually as part of its Calibre custom-installed remote radar detector system. But the K40 Defuser EX doesn't appear to have been updated in recent years and it fared poorly again in the recent test of budget-priced remote radar detectors equipped with laser jammers. That removed it from consideration for this review.

Models Tested

The first contestant was the Escort ZR4 ($450). The front laser jammers have integral clamp-on mounts as well as a variety of brackets, but nothing fit our bite-sized Honda very well, so the ZR4 transceivers were bolted to the test vehicle using U-brackets fabricated from 1/8-inch flat stock, then aligned with a bubble level.

The Escort ZR4 laser jammers work as a stand-alone system, complete with a control/display module, interface box and a third jammer for the rear plate.

The other contender was the Blinder M47 ($750), a four-transceiver system. It can be installed in any configuration, including all four transceivers in front, but on our small target car we mounted two in front and one in back, emulating the Escort Passport ZR4 configuration.

The Blinder M47 (and the otherwise identical twin-transceiver M27 model) is a far cry from the M20 we tested in 2005. There's obviously been considerable attention paid to mounting brackets, alert systems and controls.

Alerts are depicted visually by a flashing LED, audibly by the deafening piezo speaker. Those who extend jammer-transmitting time from the factory-default seven seconds may want to add a volume-control potentiometer to the audio circuit.

How We Tested Them

Twin front jammers were installed on our Honda target vehicle. A single rear jammer was mounted on the rear.

Three tests were conducted using two different vehicles. In the first two tests we measured both front and rear protection. Using a large vehicle that could easily be targeted at 3,000 feet and beyond, the third test measured rear protection only, by far the most demanding task asked of a laser jammer.

For the first series of runs, from a staging area 2,500 feet distant on a deserted two-lane rural road, the Honda CRX Si target vehicle drove toward the tripod-mounted lasers at 25 mph. When the driver approached a traffic cone placed at 2,000 feet, he radioed the laser operator with a 3-2-1 countdown. Each laser was then fired continuously, as they are by police officers, first targeting the grille area. If no speed was obtained within a few seconds, aim was shifted to a headlight and then across the frontal area until a speed appeared.

Three baseline runs with jammers off were first recorded and averaged. Using one laser at a time, we next made three runs against each laser, the average of those displayed below. One set of runs was made no front license plate installed. For the second set we installed a reflective front plate, the favored target in states requiring a front license plate since it can often double target range, compared to a headlight, the next-best target.

Test 1: Front laser jammer performance

NS = no target speed acquired

Test 2: Rear laser jammer performance

Test Conclusions

In laser-jamming performance, the Blinder M47 was clearly the better unit, jamming most lasers down to point-blank range. On larger vehicles, this extends to rear laser protection where the Blinder's twin jammer heads provided better coverage than the Escort Passport ZR4's single jammer head.

The Blinder's higher performance does entail a stiffer tariff. As noted, using twin rear heads ups the price by three C-notes and also entails some added installation challenges with a bigger labor tab for non-DIY customers.

The Escort ZR4 system is more sophisticated, offering features commonly found on high-end radar including a jammer transmitter on/off/mute remote switch. The latter is useful when under attack by a laser, allowing the driver to shut off the jammers with a button-tap, letting the officer finally get a speed to allay any suspicions.

The Bottom Line

The four-head Blinder M47 is clearly the more effective laser-jamming solution, particularly on larger vehicles and on those whose design makes them easier targets for lasers. On both target vehicles it displayed weapons-grade jamming performance against every laser gun.

In contrast, the Escort ZR4 displayed gaps in its performance envelope. But it offers adequate protection against most lasers, an easier installation and a superior user interface. At a $449 price point, its standard rear jammer may give it a competitive edge over the $479 Blinder M27. But head-to-head with the Blinder M47, in overall performance the ZR4 lags far behind.

Laser Jammers Tested

Which jammer best protects against a laser ambush?

By Radartest staffTest date: 2010

By Radartest staff
Test date: 2010