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View Full Version : Interactions between different brands of jammers?



balpo
12-21-2011, 04:21 PM
If one has both ZR4 and LI on the same vehicle do they interact or cause interference with each other? anyone actually tested this?

Laser-InterceptorUSA
12-21-2011, 05:50 PM
It's best to place the ZR4 Shifters into "Receive Only" Mode.

Cliff

balpo
12-21-2011, 07:41 PM
Cliff;
please forgive my english -
With great respect, this newbie, needs to ask a different question:
I recognize the superiority of the laser diode in terms of output between LI and the ZR4, but are the jam algorithims the same or different? In other words, can we get different signals (and/or harmonics) out of two different light sources further confusing the speed measurement and allowing closer distance to gun before JTK changes to JTG?

Laser-InterceptorUSA
12-22-2011, 01:45 AM
At best, you might be able to cut the range down very slightly. The trick to jamming is not how many jammers you have (brute force or a constant pulse jammer excluded) but rather to make the laser gun interpret a jamming pulse as its own reflected pulse. The first pulse received after sending a pulse is the one the gun accepts. Anything received outside of that window is ignored. So to jam, one must ensure that a jamming pulse is received by the gun after sending out its own pulse, but before that reflected pulse is received back so two jammers may or may not be more effective unless one is a brute force type jammer. The LI and the ZR4 are both smart jammers so unless the above criteria is met, the effectiveness of any jammer will be limited.

If, however, you are talking about "flooding the gun with light" so that it is unable to pick out its own pulse, these methods are not very effective. Although possible, the amount of light needed to accomplish would probably be quite expensive to manufacture and also not eye safe by any means! The same for less expensive, low-powered LEDs. Modern LIDARs use sophisticated algos to prevent this and some to even detect such methods.

Getting back to the original question in this thread, you do not want to run two different smart jammers at the same time on the same vehicle as they will cause each other to cross-talk rendering them both ineffective. This is why at testing sessions, it is necessary to make sure everyone else's jammer are off or the emission from an active jammer not being tested may cause the jammer being tested to become ineffective. This is also true when traveling with two or more jammer equipped vehicles in a rally or on a road trip one behind the other. Both jammers will still alert if they detect LIDAR but neither will likely jam that LIDAR due to the cross-talk issue. This is while when I am traveling with my wife, her car behind mine, her LI is always turned off and only turned back on should we become visually separated.

Cliff