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  1. #1
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    Default Why no 100% active laser jammers?

    Why aren't laser jammer MFR's going for systems that are active all of the time instead of when triggered? What is needed is a semi-robust generic technique that is on 100% of the time. When a laser is detected and analyzed, then the transmitter can shift to a tailored technique. This would assist with the poor results we're seeing due to non-detection.

    The Blinder used to be on all the time and then they switced to only being on when triggered which seems to me like a mistake. I realize they are going to have issues with the IR LED's interfering with the detection side but this can be overcome. If I could, I'd like to get an old Blinder (M-06) and join it with a Lidatek unit. The problem is, the old Blinders didn't seem to last long.

  2. #2
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    Laser diodes and LEDs would burn out in days.......Blinder m06 burned out alot due to being on 24/7

    The active laser jammer doesn't have to be on 24/7 to get a JTG performance

    PLEASE STICK WITH THE MOST MODERN UP-2-DATE JAMMERS THEY WORK 1MILLION TIMES THAN THOSE JAMMERS ON 24/7

    Spoiler: show

    Radar Detectors-V1 & BEL v995
    Laser Jammer-Laser Interceptor Quad
    GPS Camera Locator-Cheetah C100
    GPS Nav-Garmin nuvi w/Trapster
    CB Radio-Galaxy DX-949 w/Wilson 500
    Scanner-RS Pro-96

  3. #3
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    There's aren't any poor results due to non-detection, not sure where you got that idea. Most are VERY good at detecting laser, even if it isn't a direct hit.

    If you are referring to Laser Atlanta Stealth Mode, that was a feature specifically designed to defeat jammers and detectors. Most detectors and jammers looked for 3+ pulses within a certain amount of time before reporting a laser alert, in order to reduce falsing from non-police sources. Laser Atlanta Stealth mode pulses twice and then delays before shooting again, and this delay in between the pulses was enough to defect most detectors and jammers. They were still "seeing" the laser, they just didn't report it because it was rejected as a false as it didn't receive 3+ pulses in the specified timeframe.

    In general, to be able to jam effectively, the mfr's need to program the best method for jamming each individual gun into their software.

    The only constant-transmit technique that I know of that would work like you mention on ALL guns, would be to transmit a constant pulse train so that no matter what, the gun will always receive a jamming pulse before receiving it's own reflected pulse. To jam consistently at 250-500 feet, this works out to about a 2-4 MHz pulse train. Laser diodes aren't rated at frequencies this high. The Lidatek LE-10 wasn't constant-transmit, but it did use this method by pulsing the laser diodes at higher frequencies than their rated spec. But they could only do this for short periods 5 seconds or so. longer and they would burn up. And unfortunately, for their own reasons they continue to use this 5 second time limit to this day, even though they use a completely different technique now and could easily jam for longer periods without issue.

    Also, a constant-transmit jammer would be setting off every other radar detector and jammer around. This would be annoying to the detector users, plus all the traffic ahead of you would be slowing down.

    Jim

  4. #4
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    I seriously doubt there would be a problem with a well engineered LED unit. Car companies are putting LED's in tail/brake lights so they are reliable. The LED's would make a difference for initial hold off. The whole point of the game is to get your pulses into the LIDAR unit. By letting the LIDAR get those first few laser shots for free (while the jammer is off), it's able to establish a coarse range and establish a gate. Once that gate is established, jamming becomes much tougher.

  5. #5
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    There's aren't any poor results due to non-detection, not sure where you got that idea. Most are VERY good at detecting laser, even if it isn't a direct hit.
    I though I read in one of the posts that the results of all jammers weren't all that great because some weren't detecting it. In any event, the results here http://www.kc8unj.com/radar/guysoflidar/lasertests.html
    don't seem to be all that promising.

    If you are referring to Laser Atlanta Stealth Mode, that was a feature specifically designed to defeat jammers and detectors. Most detectors and jammers looked for 3+ pulses within a certain amount of time before reporting a laser alert, in order to reduce falsing from non-police sources. Laser Atlanta Stealth mode pulses twice and then delays before shooting again, and this delay in between the pulses was enough to defect most detectors and jammers. They were still "seeing" the laser, they just didn't report it because it was rejected as a false as it didn't receive 3+ pulses in the specified timeframe.
    So having a constant on feature would help when the LIDAR MFR's tweak their guns. I'm not saying it's THE answer, but it's part of the answer.


    > In general, to be able to jam effectively, the mfr's need to program the best method for jamming each individual gun into their software.
    Agreed

    The only constant-transmit technique that I know of that would work like you mention on ALL guns, would be to transmit a constant pulse train so that no matter what, the gun will always receive a jamming
    pulse before receiving it's own reflected pulse. To jam consistently at
    250-500 feet, this works out to about a 2-4 MHz pulse train.
    The Blinder M-06 did a good job against early models of LTI and Kustom Sigs so 24/7 can work. Since it was one of the first jammers that worked, I would ass*u*me it's one of the first targets of the LIDAR MFR's ECCM efforts.

    Also, a constant-transmit jammer would be setting off every other radar detector and jammer around. This would be annoying to the
    detector users, plus all the traffic ahead of you would be slowing down.
    I had a Blinder M-06 and never had a problem with it even with a V1.

  6. #6
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    I think that part of the problem with a constantly-transmitting jammer is that there are significant thermal restrictions on both laser diodes and LEDs. It's true that an LED can last practically forever when driven at nominal conditions, but nominally-driven LEDs can't produce enough power to jam at any significant distance. They have to supply a higher than normal voltage which does the job but also causes the LEDs to get hotter than they ought to. It's OK to do it for a short amount of time but you simply can't do it for more than the 10 or 20 seconds max of a typical laser encounter. Laser dioded are inherently more powerful but also generate a lot of heat. I don't think that you could design an appropriate casing to run at steady-state that would be acceptably small.

    Then there's RMR. JTW's videos showed that their detectors are always transmitting a "jamming pulse." Too bad they are about as effective as sticking your TV remote out your window when you are targeted.

  7. #7
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    The big punchthrough numbers in the Guys of LIDAR tests weren't due to poor detection. In ALL cases, the jammers alerted to the laser the whole time they were targeted, except for those jammers that were not capable of detecting Stealth Mode.

    Bottom line is there's simply no need for constant-transmit and the problems that come with it, as long as the jammers don't have any problem detecting the laser. Most guns need 40+ consistent pulses reflected back before calculating a speed, and most jammers respond after receiving as little as 3-4.

    Jim

 

 

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