12 months, first speeding ticket in my a4, not bad, eh?
03-18-2003, 06:59 PM
#25
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get a lawyer...
it's usually cheaper than the fine, and it's certainly cheaper than the hiked up insurance. They almost always get it to at least no points on your license.
03-18-2003, 11:20 PM
#26
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Ground speed radar is designed to be used while in motion...
In very lax terms, it basically picks out the 'fastest' moving thing and calculates its speed relative to the 'biggest' thing that it detects (which just happens to be the ground 99% of the time).
If the cop is coming at you in the opposite direction, his gun will pick up your relative speed (200 kph) and the gun's speed relative to the ground (100 kph). Subtract your relative speed from the ground's relative speed to get your speed if the radar detector was standing still (100 kph).
I believe that such a detector may get confused if there is something large moving with the radar (e.g. a large truck). In such a case, the radar will think the large object is the ground and will use its relative velocity to that to subtract from your relative velocity to the radar.
As an example, if the cop is driving at 100 next to a truck doing 90 in the oncoming lane, then the ground speed radar may think it is only moving at 10 kph instead of 100 kph. Thus it thinks you are travelling at 190 kph instead of 100 kph.
If the cop is coming at you in the opposite direction, his gun will pick up your relative speed (200 kph) and the gun's speed relative to the ground (100 kph). Subtract your relative speed from the ground's relative speed to get your speed if the radar detector was standing still (100 kph).
I believe that such a detector may get confused if there is something large moving with the radar (e.g. a large truck). In such a case, the radar will think the large object is the ground and will use its relative velocity to that to subtract from your relative velocity to the radar.
As an example, if the cop is driving at 100 next to a truck doing 90 in the oncoming lane, then the ground speed radar may think it is only moving at 10 kph instead of 100 kph. Thus it thinks you are travelling at 190 kph instead of 100 kph.
03-19-2003, 07:55 AM
#29
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Our radars work while in motion or stationary as well. BUt, you are correct if a larger vehicle...
is around it would detect the speed of that vehicle, then it is a guessing game with the cop. But, if they are using laser it is pinpoint accurate.