2 questions regarding radar detection...

rastaman

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Question about radar detection:

1. When my RD picks up a radar signal, has my speed already been picked up? Or does it depend on how early my detector has picked up the radar? Reason being is that if I'm speeding on a country road, if the radar has my speed already, if I'm the only car on the road, then it's pretty obvious that I'm the one that was speeding.

2. If I'm in a group of cars on the interstate, and I'm the one that's speeding, can the radar operator ascertain which car is speeding (without using visual methods)?

Thanks!
 

G39x

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Question about radar detection:

1. When my RD picks up a radar signal, has my speed already been picked up? Or does it depend on how early my detector has picked up the radar? Reason being is that if I'm speeding on a country road, if the radar has my speed already, if I'm the only car on the road, then it's pretty obvious that I'm the one that was speeding.

2. If I'm in a group of cars on the interstate, and I'm the one that's speeding, can the radar operator ascertain which car is speeding (without using visual methods)?

Thanks!
1. If you can see the cop and the cop can see you, then yes, he has your speed. Radar signals can travel and bounce a lot depending on the area. If the cop is using C/O, then you might be able to catch the signal before LOS. If he is using I/O, then it just depends.

2. Umm, not sure what your asking. If the cop is just looking at the gun and the numbers, then no, the radar gun is not going to tell that your car is speeding out of the pack, however it becomes easy when they look and they see 1 car moving a lot quicker than other cars or you are breaking from the pack.
 

Token

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Question about radar detection:

1. When my RD picks up a radar signal, has my speed already been picked up? Or does it depend on how early my detector has picked up the radar? Reason being is that if I'm speeding on a country road, if the radar has my speed already, if I'm the only car on the road, then it's pretty obvious that I'm the one that was speeding.

2. If I'm in a group of cars on the interstate, and I'm the one that's speeding, can the radar operator ascertain which car is speeding (without using visual methods)?

Thanks!
1. All other things being equal, your detector has the ability to detect the radar at longer range than the radar can register speed on you. If your detector receiver is as sensitive as the radar gun receiver (should not be an issue for a quality detector), the radar itself has to deal with 2 way path loss, while your detector only has to deal with one way path loss. Advantage detector.

However, in the real world the answer is "it depends". If the officer is using instant on radar then he may not trigger the radar until he already sees you (and waits for you to get inside his range), and already knows you are traveling too fast, he is just using the radar to confirm it and give him a more exact speed. If the police officer is using a radar that is constant on but is on the back side of a hill you may not detect the radar until you top out the hill, and possibly already inside his range. There are many geometries / situations that result in you not detecting his radar until you are at a range where he might get a speed on you.

But there are also many situations when you can get advanced warning. A detector is not a "silver bullet" to defeat radar, but it does add to your situational awareness.

2. With no visual cues the officer cannot tell which car is faster in a group. However, if he can see the group of cars at all he should be able to pick out the fastest.

T!
 

NVR2FST

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Newer radar guns will display "Fastest Vehicle".

If the PSL is 65 MPH and you are passing a semi going 65 MPH and you're traveling 80 MPH the cop's radar will display your speed and not the semi's.

In the case of "constant on" radar you will almost certainly get plenty of warning. With "instant on" radar the cop will almost always get your speed before you can slow down to the PSL.
 

InsipidMonkey

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With most radar guns, the operator can switch between strongest (default mode, usually corresponds to the closest vehicle), or fastest. Fastest mode is not allowed in some states because it can be difficut to determine which vehicle is actually speeding in certain situations.

Token is right on regarding the range issue.
 

LouG

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G39X is correct line of sight is everything to the cop. If he can't see you should not book you.
However, I have seen older X band radar units register a speed off a vehicle when the return signal has bounced off a median barrier or some such and is still out of sight.
I also bet that some cops have written tickets on that.
 

rastaman

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Thanks everyone for the replies.
My biggest concern is if I'm on a deserted country road. I'm flying down the road, the only car for miles, and a cop hidden down the road a few bends away has his radar on. He absolutely can't see me. My RD goes off, I slow down, and then eventually pass by the cop.
So, I am clearly the only car on the road...if he registered a speed while I was speeding, it would be pretty obvious that it was me.
 

SaratogaLefty

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I believe if he is "hidden down the road a few bends away" and he can't actually see your car I don't know how he would be able to "shoot" you and get a reading. This assumes he is using constant on radar as mentioned above. If he is using instant on then he will wait until you are almost right upon him before he triggers the gun and most likely you will be nailed. That's why you need a "rabbit" running a 1/4 to 1/2 mile ahead.
 

Boozehound

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While many of the newer radar units can read strongest and fastest, things get dicey when that radar is trained on a highway with three or more lanes with a bunch of traffic on it. With only a few vehicles present it's much easier to tell who's fastest and who is likely strongest (like a big truck).

The best long range RDs like R7 and V1G2 have exceptional sensitivity. Against I/O the idea is to pick up the radar when a vehicle in front of you is targeted. This can work well with the right amount of traffic and also varies greatly with terrain. Hilly, curvy, and lots of vegetation will substantially reduce your range of detection. Then you have the selectivity of the radar operator. If he only targets vehicles that are obviously in wretched excess that makes it tough if you're the only one running 90+. Hence the suggestion to use the rabbit.
 

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