Does anybody know the sampling frequency of a cop radar?

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Discussion Overview

The discussion revolves around the sampling frequency of mounted 360-degree police radar systems, specifically in the context of a user who received a speeding ticket and is questioning the accuracy of the radar reading.

Discussion Character

  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant seeks to know the sampling frequency of mounted 360-degree radar, distinguishing it from handheld devices.
  • Another participant questions the reason for the inquiry, prompting a personal account related to a speeding ticket.
  • The individual who received the ticket believes their speed was misrepresented and considers using the radar's sampling frequency as a defense in court.
  • A participant suggests that understanding the make and model of the radar, along with obtaining its instruction manual and calibration certificate, is essential for evaluating its accuracy.
  • There is a discussion about the nature of 360-degree radar and the implications of its sampling frequency, including the distinction between Doppler radar and laser speed detection systems.
  • Concerns are raised about the reliability of information obtained from online discussions in legal contexts.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the specifics of the radar's sampling frequency or its implications for the user's situation. Multiple viewpoints regarding the nature of radar technology and its operational details remain present.

Contextual Notes

Participants express uncertainty about the definitions and operational characteristics of different radar systems, including the potential for misinterpretation of speed readings based on the radar's design.

Who May Find This Useful

Individuals interested in radar technology, legal implications of speed enforcement, and those seeking to understand the technical aspects of police radar systems may find this discussion relevant.

llatosz
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More specifically, does anybody know the sampling frequency of a mounted 360 degree cop radar? NOT a conical/directional hand-held radar gun.
 
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May I ask why you want to know?
 
Yeah sure.
Its because I got a ticket going 83mph in a 70mph zone, but I am POSITIVE that I wasn't going any faster than 72mph at any time.
What happened was that it was late in the evening and I was in the fast lane when three cars zoomed past me and all quickly veered onto the nearest exit. Just moments after the last car passed and I said "woah" to myself, i noticed a cop car ahead going slow in the middle lane. I immediately looked at my speed and noticed it was just a hair above 72mph so I cooled it to 70mph and eventually caught up to him and passed him going 70 and got pulled over and he said to me "ya know you can't just slow down when you see me and think "oh everythings okay", my radar detects behind me in all directions". I briefly told the officer that i think he might have detected another car that I saw speeding by, but i wasn't going to argue with him. He did make a note of what i said in the ticket though.
So if the sampling frequency is low enough, I was thinking i could use that argument on my court date
 
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You need to know the make and model of the radar.
You need to get a copy of their instruction manual.
You need to get a copy of their operational guidelines.
You need to get a copy of their calibration certificate for that instrument.

What do you think 360° radar really is ?
What do you mean by sampling frequency ?
Is it a doppler radar or a differential distance system like laser speed guns ?

Note that doppler radar reports the highest speed detected, so on a corner the top of a motorcycle front wheel rim will return a reading about 160% of vehicle speed. As the bike straightens up towards the doppler radar the reading drops to 100%. That is one reason why police think the rider slowed down when they were seen.
 
I'm sorry but we don't assist with legal issues or matters related to them. Please contact a lawyer and/or other professional who can evaluate this. Besides, how would it feel to arrive in court only to have incorrect information because a few strangers on the internet with the best of intentions were simply wrong?

Thread locked.
 
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