Had my first experence with a radar jammer the other day. Was on the highway in a long line of traffic. My Valintine 1 was telling me that there was a Ka radar behind and was showing max strength. Kept looking but could not see any cop. The two lane road we were on then opened up to 4 lane and a Honda accord behind me passed and the Ka radar went away. So assume that the Honda was running a jammer. If so it should be very easy for the police to pick out those running jammers.

tom...

 

Most lilkely you experienced a radar detector with a very leaky local oscillator. All superhetrodyne based radar detectors leak their local oscillator, (LO) out their antenna. Some detectors just leak a stronger signal. If your detector was smart enough, it wcould tell the difference between a sweeping LO and the different types of police radar.

 

This thing had the V1 pegged on the strength meter. Most other leaking detectors will only get one or at most two lights on the strength. The V1 is not a dumb detector, it does have the ability to filter these but I only keep it on the mid level of filtering.

tom...

 

I don't think there is such a thing as a Radar "Jammer", :nono: if there was, and they were made legal, Mike Valentine would have them for sale............there are however, Laser "Jammers" on the market, and the LaserEcho by Lidatek is the best out there.........and yes they are legal.
:yesnod: http://www.lidatek.com or 888-324-6911

 

No, they are out there, or at least being sold as radar jammers :rolleyes: . All test of them that I have seen say they do not work. And if the one I ran into is any example the tests are right.

tom...

 

Nope, they're not legal in most states. There was a company that built them in San Jose - they called the product the Phantom RCD, and had another version of the same OEM called the Scorpion RCD. From an aesthetics point of view the product was a bit clunky - took up the entire glove box, ran pretty hot...and while the front panels were pretty retarded at best (it had 2 LED's, power and threat), it had none of the features of the Valentine in terms of specific band for threat, no KA support, worked intermittently, and also set other radar detectors off. Would love it if it worked better, unfortunately, Valentine seems to do the better trick.

 

Why is it that this topic surfaces about every 6 months and there is ALWAYS heresy all over the thread.

OK, I'll keep this short...

The legality of an [active] "jammer" is not state to a state issue. It's a federal thing. The FCC has outlawed them. This is not to say that Companies don't still build, market, and sell them. These companies/their devices are a joke!
Real jammers are [VERY much] illegal!

Most new radar guns let the officer listen to the doppler echo when shooting radar (this means they would hear it if you are trying to jam them!)!

Laser jammers are a joke (for the most part). Period. Laser travels at the speed of light. You are not going to fool a Lidar gun.


[Modified by EdwardETraylorIII, 8:44 AM 1/9/2002]


[Modified by EdwardETraylorIII, 8:45 AM 1/9/2002]

 

If you have a ham radio license, you can legally transmit on the same frequency as the police radar guns. All you would need to do is have a mic input and FM modulate the carrier.

To jam a police radar signal, you need to pick whether you want to jam the police radar receiver or fool it into reading the wrong speed. The other big problem is that you would need to make a jammer that would work on all three bands, or at least K and Ka bands.

Depending on the design of the gun, fooling it would be very difficult to do cheaply today. There are many radar gun designs and it may take a slightly different technique to fool each gun. It depends on the gun's design and weaknesses. There are at least two different techniques to fool a doppler radar. First would be to AM modulate a signal that is close to the frequency of the cops gun. You would modulate the carrier with an audio tone that would be the doppler shift corresponding to say 55 mph. The signal would have to be strong enough to overload the front end of the radar gun and cause it's mixer to go non-linear and demodulate the audio tone. the audio tone would then go to the DSP chip in the gun fooling it. The other much more expensive way to fool the gun would be to phase and frequency lock your jammer to the incoming radar signal. You would then have a DSP chip control a PLL synthesizer that would generate a microwave signal that had the correct frequency offset coressponding to the Doppler shift. This would require less power.

If you decide to jam it using raw power, then you better not be the only one flying by at 100mph. The cop will quickly realize something is wrong

 

As mentioned, radar jamming is illegal per the FCC (federal felony). And most, perhaps all, radar jammers you can buy are junk.
Lasers are regulated by the Food & Drug Administration (!), and there is no federal law against jamming them. About 6 states have state laws against jamming, can't remember which ones. Laser jammers do work, most popular seems to be the Blinder.

 

Radar jammers are illegal (federal law). Laser jammers are not illegal. Car and Driver has tested jammers and found them all to be ineffective and some only effective at 10 yards (radar jammers). The amount of power required (both radar and laser) to saturate the police receiver and prevent it from making a speed measurement is sooooo large that it is impractical. Transmitting a tone on the radar bands to force a police receiver to indicate a lower speed is difficult for several reasons : 1. Large transmit power is required. 2. You must transmit on the exact same frequency the police radar gun is operating on. 3. The speed you have selected to force the police gun to read just might be excessive (55 in a 25 zone). 4. An officer seeing you obviously exceeding the speed limit and his gun showing 35 mph is probably going to stop you and investigate, and will likely issue you a citation for interfering with a police investigation and also for operating a radar transmitter without an FCC license.

 

As previously said, active radar jammers are illegal according to the FCC -- and they are very easy to detect.

Inactive radar jammers are junk.

Some Laser jammers do work and they are legal. However, for them to work, since there is very little spread and scatter from a laser beam, the cop has to target your vehicle within about three feet of where the laser jammer detector/source is mounted. On a small car, you may get away with one detector/source. On a large 18 wheeler you may need 10 scattered over the front end to be safe.

I saw a small Honda with one mounted on the front license plate. I also saw the cop take the laser gun and look at it like he was confused after we went by doing over the speed limit. The unit, at the time, cost about $400.

On my '92 Corvette, since the front is so "rounded", I imagine I could get away with one detector/source mounted on the front where the license plate is mounted. I could paint the front end flat black, put covers over my fog/turn signal lights, and put an anti-reflective coating on the windshield (it has such a slope it probably doesn't matter) and travel past the laser gun at 160 mph with no problem. However, radar could get an echo off of my chassis, engine, radiator, and gold in my teeth -- but not the fiberglass composite body.

Tom Piper