Radar Gun and GPS question
 

I was curious how often do officers have to have their radar guns calibrated/tested?

I was also curious if anyone knows how accurate the MPH on a GPS are?

My double din radio is able to display driving avg. mph, overall avg. mph and maximum speed.

Re: Radar Gun and GPS question
 

The radar/laser guns have to be calibrated annually.

My portable Garmin GPS is spot on. I got pulled over a couple weeks ago and when the officer asked how fast I was going, I told him what speed I was doing when I first saw him. He said, I was correct and even showed me his laser gun to prove it; super nice State Trooper.

Re: Radar Gun and GPS question
 

Could a court of law dispute if you were to bring in evidence showing that your GPS shows a recorded speed that is less then the police officer.

Re: Radar Gun and GPS question
 

Unless you had someway to take a screen shot at the exact moment the officer radar/lasered you, no it wouldn't stand up in court.

Re: Radar Gun and GPS question
 

How bad is the ticket lol

Re: Radar Gun and GPS question
 

Some municipalities calibrate the Radar guns daily.

Re: Radar Gun and GPS question
 

Well the thing is did not dawn on me to take a picture then or even show the officer. I took a picture when I got home with my camera and it has the time stamp.

It is saved on the radio until you reset it. I would have to have a judge follow me to the truck to view it as I can not take the radio into court

Bad enough to have a mandatory court date.

Re: Radar Gun and GPS question
 

I don't know how it is in MO, but in Indiana that is at least 30 mph over.

Re: Radar Gun and GPS question
 

Outch so reckless then? Atleast here in wa that's what gets u and instant court date

Re: Radar Gun and GPS question
 

So take the pic with the time stamp with you to court, and hope for an understanding judge. how much different is the "clocked" speed versus your "GPS" speed? I've been pulled over for speeding while being passed by another vehicle. The officer actually clocked the other vehicle and tried to pin it on me. I explained my story to the judge, and while he didn't throw it out, he did reduce the fines substantially.

Re: Radar Gun and GPS question
 

I had the same thing I was paced I asked for the records of he last calibration of the cop cars speedo and the times he wrote down were all messed up thrown out

Re: Radar Gun and GPS question
 

There is a 20 mph difference. Which if you go by my GPS I should just have a fine and no court date.

Re: Radar Gun and GPS question
 

like everyone has said. annualy ( 3 months). i highly doubt it would be that off. Either something is up with gps and its throwing a bad speed or the radar is out of calibration. It happens very easily. If its anything like down here, they would look at the gps pic, but probally do nothing about it because you installed it yourself. not saying you did or would, but ppl would put speed lesseners on the gps just to get out of tickets. So keep that in mind,

Re: Radar Gun and GPS question
 

GPS's are accurate if a speed is constant for a long period of time. If your speed changes rapidly (faster, slower, faster, slower) in a short period of time they are incredibly inaccurate. Where you looking at your GPS and not your speedo?

Radar/Lasers are certified annually (once a year) by the Department of Agriculture here in CO. Operating guidelines for use of any laser/radar for speed detection are:
Radar-
Lamp test
Tuning fork test (55/35mph)
Prior to use/after use (Daily)

Laser-
Lamp test
Scope test
Delta speed test
Laser test
Prior to use/after use (Daily)

Truth be told, you know your speed.
If you did it be a man and take the punishment.
If you know you didn't, go to court and plead your case.

Re: Radar Gun and GPS question
 

If the officer hit you wait laser and I were a judge, I would probably believe that over a picture of a GPS. I wouldn't put much faith in this but its worth a shot.