Cop laser jammer

[WilliamN]

I want to build a simple laser jammer. I believe all I need are a few IR leds. Does anyone know what frequency I should pulse these at? I thought about building a circuit and just using my laser detector as an idicator to adjust the oscillator. Any thoughts?

 

[Johnson777717]

I think jamming these types of signals may be against the law. You may want to check your local regulations before spending time on this.

 

[WilliamN]

Hey, I live in TEXAS. Everythings legal here! :lol: Besides, I don't care if it is or not. I am going to hide it :twisted:

 

[vaineo]

Well regardless of what state you live in they will sell you one of these, so I don't know how strict they are on those rules. But then again they sell things like MIRT's that just havn't had a ruling and at the time are legal.

 

[crust]

Hey, I live in TEXAS. Everythings legal here! :lol: Besides, I don't care if it is or not. I am going to hide it :twisted:

For those of you not from Texas, I live there and that statement is not far from the truth. In fact, having open containers in the auto was legal until just 2 or 3 years ago. (The driver could never have one, but the passengers of age could).

Now having said that, actively tampering with the radar definately is not allowed. If your system is passive then I do not believe there is any current regulations. (By passive I mean along the lines of using radar absorbing material, etc).

 

[jem]

:lol: I could second that, but I left Houston in 2K.

 

[0mega]

Cop radar

Hey, wassup

I live in australia, but i know how the radar works. The radar works by sending out a radio signal , which hits the car. THe reflected wave differs in frequency (by doppler effect).

It is technically impossible to jam radar (hey, the us military would love to, but they can't yet )... to do this you have to actively process and modify the signal. If you knew the frequency of the wave coming in, calculated the doppler deviation, the send back a wave which would negate the reflected wave, your car would be invisible (cool), but such systems would cost $$$$$$$$$ (millions)

It might be possi ble to use something, say, to jam it, such as broadcasting "Crap" waves at about the right frequency and amplitude.

CHeerzZ
JB

 

[Eclipsed]

He is talking about LIDAR, which uses a laser instead of radio waves.A company called Passport has a jammer, which I've installed on a few vehicles and had a chance to take a close look at it.Its was a very simple, I could be wrong, but it didn't appear to have a circuit that pulses the LEDs.If you figure it out, let me know, from what I hear they work very well.

 

[pike]

Re: Cop radar

It is technically impossible to jam radar (hey, the us military would love to, but they can't yet )... to do this you have to actively process and modify the signal.

It is possible today, it is something called chaff. I've been told that is disperses negatively charged ion-aluminium pieces of foil. 'Air Force One' ( the plane the US president gets to fly in) is equipped with this sorta stuff, but it comes in the form of flares, not grenades.

The negative ions equalize the positive half of the radar signal (chop off the top half of the radar wave) and only the negative half of the wave is relfected back into the reciever. This disrupts the radar frequency.

In theory you could use positively charge ion particles to alter half of the radar signal and relfect it back altered... but yeah very expensive option just to avoid speeding fines...

EDIT: Are you forum member at overclckers.com.au, JB ???

 

[WilliamN]

Yeah, I am not looking for a Radar jammer. Just a laser jammer. You can buy those liscense plate frames with the LEDs in them. Something like that. I am just going to experiment and measure the output with my laser detector.

 

[0mega]

Re: Cop radar

Are you forum member at overclckers.com.au, JB ???

why?? no, i'm not, what is it? I'll check it out

 

[pike]

Re: Cop radar

why?? no, i'm not, what is it? I'll check it out

don't worry, someone on the forum uses the same "JB" name. They are also live in melbourne. Over there they do insane stuff like make their own fan speed controllers, computer water cooling systems, liquid nitrogen cooled computers, LCD screens...just completely insane stuff.

sorry typo: www.overclockers.com.au

Sorry guys i know this is off topic...

 

[1997 GA16DE]

He is talking about LIDAR, which uses a laser instead of radio waves.A company called Passport has a jammer, which I've installed on a few vehicles and had a chance to take a close look at it.Its was a very simple, I could be wrong, but it didn't appear to have a circuit that pulses the LEDs.If you figure it out, let me know, from what I hear they work very well.

anymore info on this? Does it protect you from all angles?

 

[the_pilgrim]

Hi All

i am new to this forum and to electronics but not to laser jammers. I have wanted to build one of these for months maybe i can help you help me.

Here is what i know

As described in earlier posts the police gun fire an IR signal at the car and calculates the speed using dopler shift.
The IR signal is a galium arsenide laser diode at 904 nm

The jammer sits in the car grill or number plate and detects the incoming IR signal. This triggers the jammers IR diode to emit on the same frequency thus killing the police signal and setting off an alarm to tell the driver of the speed trap.

The jammer will jam for 5 seconds and then allow the police to get your speed. This should give you enough time to slow down to the legal limit. If the police cannot get your speed at all, they will know you are jamming them.

The jammer will then reset after 60 seconds ready for the next trap.

These Jammers are not illegal in the UK as they have legitimate uses (eg opening garage doors, gates etc.) and it is not illegal to transmit light in the UK. HOWEVER if you are caught jamming a speed trap you COULD be charged with 'obstructing a police officer in the course of their duty' ALTHOUGH most of these speed traps are manned by civilians

Please dont get me wrong im not some crazy guy who wants to drive at 100mph every where. i just feel that if the police are going to become more covert and underhand in the persuit of normal drivers and extra revenue, then normal drivers have to defend their wallets and their licenses: Those people who live in the uk will know what im talking about :x

Any plans or idea anyone has will be appreciated here

post any further questions you may have.

Regards

The Pilgrim

P.S. laser diodes available here www.lasermate.com/GRImodule.htm

 

[stevez]

I have a number of friends in law enforcement and any mention of detectors or jamming usually gets a laugh out of them. They generally agree that if you are a relatively careful driver and stick close to the speed limits that a warning might be of some benefit. An example of this might be if you fail to notice the speed limit dropped as you entered a populated area. If you are the kind who would drive faster because you feel protected their feeling is that you are at least as likely to get ticketed, if not more so.

A friend of mine (law enforcement on major hiway) points out that it is his observation that a vehicle is speeding that is the basis for the ticket. He has tools available such as radar, the laser, his own speedometer, timing tools, etc. Some of these are active (radar, laser) and some are quite passive and you can't tell they're being applied to you until it's too late. These are all verification tools - the primary enforcement tool is still personal observation.

Not sure what the laws are like elsewhere but it would seem that detectors and jammers might be an aid to someone who is forgetful though it would seem that they only work on some things that can be used by the law enforcement folks. If you'd increase the amount of drive time over the speed limit then you'd be exposing yourself to greater likelihood of observation/verification by passive means.

 

[captainkirksdog]

As a former police officer I know that all I need (in most states), is two points a known distance apart, a stopwatch, and a sworn affidavit to haul your butt into court. As a current electronics geek I say do anything passive you want. Redirect, deflect, or absorb whatever signals are being shot your way, but be cool when it comes to jamming or emiting any kind of false signal. Besides, I might be cruising near you and get busted instead when your jammed signal bounces off me!!! Grrr!!

 

[DoctorMemory]

Re: Cop radar

It is possible today, it is something called chaff. I've been told that is disperses negatively charged ion-aluminium pieces of foil. 'Air Force One' ( the plane the US president gets to fly in) is equipped with this sorta stuff, but it comes in the form of flares, not grenades.

The negative ions equalize the positive half of the radar signal (chop off the top half of the radar wave) and only the negative half of the wave is relfected back into the reciever. This disrupts the radar frequency.

Um, wow, this is SO wrong, it's hard to tell where to start...

Chaff is just (large) bits of aluminum foil. The reflect the radar directly. creating a false target. The intent is to trick radar-guided missles into flying into the chaff instead of the plane (which is supposed to take evasive action immediately after dropping the chaff). Think of it as an electronic smoke screen.

Flares are used as decoys for heat-seeking missles. Same principle.

I'm sure Air Force One and most military bombers (and possibly fighters) have both.

 

[jrz126]

I read somewhere that the laser needs a semi flat piece of metal to bounce off of, like your license plate. Is this correct? I remember seeing something about a license plate cover that would deflect the laser so it wouldnt register back at the gun.

(I might be wrong about this, but aleast it's better than trying to throw pieces of foil out my window when I go speeding past a cop :lol: )

 

[JohnBrown]

I'm not a cop, or an ex-cop, but I think you should all grow up. Speed limits are in place to try to SAVE LIVES, not to stop people having "fun". Why is it that every w**ker in a car thinks that he (and it's almost always a "he") can drive safely at high speed? People are killed on the roads in numbers that would be regarded as totally unacceptable if attributed to any other activity.

 

[tom2000]

Why is it that every w**ker in a car thinks that he (and it's almost always a "he") can drive safely at high speed?

because here in america we have good roads so we should be allowed to speed, you guys on a farm, i mean england, have crappy roads so you should always obey the speed limits