speedometer vs. GPS
 

Has anyone noticed a big gap between your boat speedometer and a GPS? I've noticed as much as a 10mph difference and was wondering which was more accurate? I am assuming the GPS since it is accurate on the road. It is an auto GPS (Nuvi 350) with the Garmin winnepesaukee map on it. Looking forward to hearing if anyone else has noticed this.

GPS - as accurate as you will get
 

I'm amazed how accurate my boat speedometer is. It is usually within a MPH or two of the GPS reading. You can assume the GPS is very accurate, although it may have short glitches if the signal is weak.

Yes, boat speedometers are notorious for being off. Since most of them work on water pressure there are many variables which can affect an accurate reading. A GPS is extremely accurate at determining your speed.

As an fyi,... My boat speedometer get progressively more inaccurate as I go faster. Between 10 and 20 mph my speedo is relatively accurate, but when I speed up to say 50 mph on my GPS, my speedometer on the boat reads 55 mph.

Dan

What I noticed is when the boat is reading 35mph, the GPS is reading 45mph. Last thing I want to do is get pulled over for the "law that shall not be named" :laugh:

My Faria speedometer/Bravo 3 leg pitot is pretty darn accurate, according to my GPS. It's only off at speeds below 15 and above 45 or so, and then only by about 1.5 MPH at WOT.

A GPS calculates speed by change of position over the time between position readings. Theoretically if in the time between readings I went like a bat out of hell and turned around and returned to my starting position the GPS would report my speed as zero since I hadn't moved. The point is that the GPS is making some assumptions to calculate speed.

First is that the GPS has no way to know how you got from point to point. It assumes a straight line but you may have been traveling in a curve. The faster you are going the more distance you travel in a sampling period and the more it would effect the difference between a straight line and a curved path. If you are traveling in a straight line the accuracy is going to be higher. BTW, curved paths would result in lower speed calculated than reality.

Next, how accurate is your GPS positioning. Since speed is calculated by position and the sampling periods are relatively short, if the positions are accurate the speed calculation will be as well. Accuracy is a attribute of the design of the unit, the installation on your boat (antenna position, etc) and the ability to receive accurate satellite signals from minute to minute. There can be a lot of variability.

Not so fast there
 

You're partially correct, I believe a lot of GPS receivers use position differences over time as 1 input to the filtering used to calculate and smooth speed. But the most accurate input is averaged velocities calculated from the Doppler shift of the carrier signals from the satellites. Measurement of the frequency difference is very accurate and knowing about where you are on the Earth and where the satellite(s) are going you can calculate which portion of the velocity vector lies on the Earth's surface and hence your speed. Somewhere on one of my PCs I have a good paper that describes this understandable terms ... alas it isn't on this one. :(

Accuracy is not really that important, as long as the offset is consistent. It doesn't matter if the GPS knows exactly where you are, if it is off by 3 meters the calculations would be correct as long as the 3 meter offset error remained constant.

Most GPS units are doing several samples per minute, so even if you were traveling a non-linear route the speed calculation would still be accurate enough for anything other than a boat doing continuous donuts in a small area.

So what would happen if you were going 55 (which you thought was 45 due to your faulty speedo) and you got a ticket. How can you know your actual speed if your speedometer is that far off? I know one thing...I would be taking that one to court to let the judge decide. As far as I know, GPS is not required equipment...

Surprised
 

I was surprised how accurate my 23 year old VDO guages and pitot were when I took the GPS in the boat. 1-2 MPH difference all through the speed range max.

Speed...
 

Probably the same thing that would happen if you were actually doing 76 on Rte 93, but you THOUGHT you were doing 65. It is your responsibility to know how fast you are travelling. I doubt you would find a sympathetic judge.

keeping stock pitot is the key, on my old speedboat the oringinal pitot was within 2 mph of the GPS, the bracket broke and the new one that replaces it was off by 5-7 mph, not sure if the pcikup was longer on the old one or shorter. On my toon it's off by a consistent 5 mph at just about all speeds.

I somewhat disagree. Measuring speed accurately in a vehicle is much easier than on a boat, and speed limits have been a much more predominant item in automobile law vs. boating law.

It should be fairly clear by now that the reality is you're not likely to find yourself in this scenario. You would pretty much have to be traveling near the speed of light before you are going to get a speed limit ticket.

0.1 mph
 

My Garmin GPS steady state speed accuracy is 0.05 meters/sec or 0.1 mph. Position data is updated once per second. I might accept the GPS reading over the speedo.

While there are position errors in GPS, those errors change slow relative to the once per second update rate so distance traveled in one second is very accurate.

I have bought 2 "paddle-wheel" speedometers for 2 different boats. The packages included directions on how to accurise them. Basically you needed a measured distance so you could "clock" the boat and adjust the gear accordingly. There is probably a similiar requirement for "pitot tube" versions.

I doubt most factory boats have this procedure performed on them. Speed precision apparently was not considerred that critical since speedo/GPS discrepancy is occasionally discussed on other boat forums I visit.

If you want to accurise your instrument it is simpler to use a GPS than a measured course. During a calm period (no wind or chop) operate your boat at various speeds on a lake or large pond. Compare the readings. Adjust your speedo according to the directions. Repeat the procedure until you are comfortable with the results.

If you don't have, and cannot get, directions for your version examine the back of it for calibration access. Make a note of the current settings if possible. Then expiriment to see what makes it show higher or lower.

If you are not comfortable working on these systems then make a mental note or written table of the discrepancy at various speeds.

That's all I think I know about that.

Good luck!

LEO article
 

I was reading an article posted in 'Heloise' the other day. A LEO from Texas says to never use the GPS as a spedometer as it is inaccurate????

He claims to be pulling people over who says: 'Officer, My GPS says I am going the speed limit!' They were traveling over the speed limit. He hinted on Heloise that people should not use their GPS as a speedometer as they are inaccurate.

As stated in this thread I find the boat's speedometer readings off from my GPS reading. I am planning on using GPS to keep within the speed limit on the lake. I have observed my GPS as 'dead on' with the speedometer readings in my truck. I also heard that stored data in GPS is being used as evidence in court cases.

Should I be confused????? :confused:

When going in a straight line your GPS is extremely accurate. The problem becomes if you take readings while taking turns. Since your GPS only works on forward momentum, accuracy diminishes while turning. The sharper the turn the less accurate it becomes. I would trust my GPS whlile going straight way more than any speedometer.

As far as GPS being used as evidence in court cases, I have not heard of this, but who knows, in this day and age of "big brother" looking at everything we do I wouldn't doubt it. I have heard of On Star being used in court cases however.

Dan

ishoot308, great explaination of the gps speed. I have seen in many situations that in a slight turn it will actually show a greater speed then the true speed. This is why when racers are trying to break speed records they have to complete two passes to ensure accuracy.

My gps speedo needs a new battery, but livorsi wants $200 to do the replacment. However, there is no law that I have to have a speedo on the boat. So frankly I don't know how fast or slow I am going. Would be very hard to make that stick in court. ;)

On Saturday, I tested mine out. The speedo is accurate up to around 45 to almost 50, then it goes my way :laugh:

I will be testing the Garmin against the Tom Tom next weekend. As of now, the best GPS I have in my boat is the iPhone, with a $9.95 Navionics East app in it. I can see everything better, including the marker buoys, than with the Garmin 440. Interestingly, I have the optional $200 card in the Garmin.

$200? Depending on the model, that is like 70-80% of the price when new. You should bring it by, my guess is the battery could be replaced for about $10.

I have been online and apparently if you send it back to livorsi they give you a new model for $200 as an exchange. I have been told I can run a line to my new GPS once I get the network up and running which may negate the need to replace the battery or unit at all.

But frankly, I don't care what speed I am at. I am driving safe and prudent. Until there is a law that says I have to have a speedo it really doesn't matter.

I put a portable GPS in my boat for a weekend and wrote down the tachometer revolutions for particular speeds.
My pitot tube kicks up over 60 on Lake Winnisquam.. :rolleye2:

My speedometer sucks. It doesn't even read until about 25 MPH and then when it does, it's off by 10MPH when compared to my GPS.

However, my boat tops out at 48.5MPH according to my GPS, and that's on flat water with only two people. I don't see a ticket in my future anytime soon:yawn:

There's that "Responsibility" word again...
 

The statement ignorance of the law is no excuse is centuries old:

http://www.rbs2.com/cc.htm

The same source continues:

Please explain how someone on a boat is supposed to know exactly how fast they are traveling if their boat does not have a speedometer? There is no law that requires a boat be equipped with a speedometer. That would be my challenge to a judge if I were to get a ticket.

I am not being ignorant of the law, as I am perfectly aware that there is a speed limit. Without a speedometer, I might be ignorant of my exact speed however.

Yeah tell it to the judge!
 

Yeah, I suggest you don't try tellin that to the judge. My pickup doesn't have a speedo or doors for that matter. I got a speedin ticket that night when that college boy Hooper just kinda rolled out'a the truck on the salt pond road, and it didn't do no good when I told judgy I couldn't tell how fast I was going cause I aint got no speedo. No, give up on that excuse mister.

Absolutely would bring it up to a judge. It is a lot easier to gauge ones speed in a vehicle on a road than in a boat. For one, in a car you can compare your speed to other vehicles. You can judge your speed based on time/distance to fixed objects. In a boat, there are way to many variables to even think about guessing speed.

Are speedometers required equipment in cars?

Boat Speed
 

Seems like if you don't have a clue how fast you are going....maybe you shouldn't be behind the helm.
If you want to captain a vessel, you should be ready to accept responsibility for all aspects of the operation of said vessel. Short of that, keep your boat tied up to the dock. That will help make the lake safer for the rest of us.

I have been driving boats my entire life. If you don't have a speedo it is difficult to know exactly what your speed is. If you know your boat you know that based on the RPM level where around your speed is but no one knows exactly without a speedo gps or otherwise.

As an example going at cruising speed on a flat windless day at 3000 rpms feels slow (in my boat at least)

You change that into a strong head wind with 2 - 3 foot chop it feels like warp speed. It is all relative. However, you may actually be going slower.

As long as you are traveling at a safe and prudent speed for the conditions the # is arbitrary.

Be careful what you complain about!
 

Of course if enough folks complain that is is wrong to have a speed limit but not require speedometers on boats, some intrepid legislator will listen and file legislation to require speed measurement devices on boats travelling on waters with limits.

And then some of those same folks will complain about "nanny state" and "ridiculous legislation".

And this, my friends, is a perfect example of how we get all these rules and regulations that we are all (most of us anyway, myself included) so fond of complaining about! :)

agreed Skip... However that would be extremely tough to regulate considering boats may not or may not have been manufactored with them. The logistics would be crazy.

Aye!
 

Aye, Not like going down the pond chasin' bluegills and tommycods...we're talkin' 'bout up around 40 knots or so- or maybe 22 in the wee hours. You certainly know if you're approachin' the max legal speed- 'specially if there's a small 3-4 foot chop on the lake. If you have the urge to go max legal speed and not a prudent one- then get yerself a good working speedo or one o' them new GPS things. Any keep yer eyes open an' not on tha' damn electronics stuff!

what about bumps
 

We use the GPS on our sleds. My wife has noticed many a time when traveling across a lake at 90-100mph that if she hits a bump the gps will jump up to as much as 150mph.
I’m not sure if this is due to the higher rate of speed or what but she has never commented on it happening when using it on her boat which reaches speeds of 50, or on my baja which gps’s at 66.

Required equipment?
 

I do not see where a speedometer is required in a car, nor do I see it as required in a boat.

If it was required in a car, I would expect that it would be part of our vehicle safety inspection. While not required in a car, I would not really want to stand before a judge and say my speedometer cable (I have a really old car) broke three months ago, so I really didn't know I was doing 70 in a 55 (my really old car is a big old beast that rides like a dream). I think that once the Judge stops laughing at me(like this :laugh: ), I would be reaching for my checkbook to pay the fine. Judge would then thank me for making his day.

I think that if any of us get a speeding ticket on the lake, and our defense is that we have no means of telling our speed, the Judge may again thank us for making his day (that being right after letting us know just what the fine would be).

Bottom line is we have a speed limit, like it or not, and some of us will find ourselves in a position of being caught exceeding the limit (just as we may on our roadways), and when we do, we may very well have to pony up the bucks. We may be able to challenge "radar" qualifications, but the lack of a speedometer would not be a defense, at least in my humble opinion.

Regardless, go out and enjoy the lake, and if you see the Upthesaukee as you fly by me, please do give me a wave...I do wave back! Enjoy your summer.

Nothing to worry about
 

the laws have been passed, no doubt about that. But the State gutted the MP budget, which had already been gutted. Let them feel good about what they've done, and don't worry so much about some silly measuring device.

I don;t really care though. Heck, I joined this forum to talk about sailing :emb:

I'd expect there's a limit
 

Yes speedos are required equipment on cars. One of the times this topic came up I even listed the Fed regulation to that effect. There's also an accuracy requirement, I think it was +/- 2%. In any case you might plead to the judge "I didn't think I was going that fast" and if you were only 5-10 mph over, he might believe you. On the other hand if you doing 80+ mph in a decked out 300K$ gofast with twin supercharged engines ... my guess is he's not going to buy the story.

whats next?
 

I know of 4 boaters who have gone up to between 38 and 48 foot cruisers after selling their performance boats.
We are a 2 boat family and always have been. I'm selling my 25 Baja and we are looking to upgrade to a cruiser. We don't need one but if we are going to boat on this lake we are going to be comfortable doing so.
Even in my wife’s 26 foot Chaparral you get banged around on any weekend. My Baja is great but I'm not going to waste my money if I cannot enjoy it to its full potential. So we are looking to buy a boat we probably would not have but because of the new speed limit we will.
So all the boaters complaining about all the big waves, well it is only gonna get worse.
Blame the speed limit. Oh and what about shore line erosion?

Watch out. They'll go after the size of the boats next.......

don't do anything rash.. news to follow. ;)

does not matter
 

It's just much more economical to become a one boat family. The lake isn't so bad now but when it picks up to its original level prior to this recession even in the 25 outlaw there are days when I just wish I was in a wake maker instead of on the receiving end.
I know that at one time those proposing the speed limit were also boasting they were going to go after the big cruisers next but I just do not see that getting any support. Just look at how many big boats there are and many do not even leave their slip.
Guess we will have to wait and see.
Someone said to me recently "don't worry eventually these people pushing the unnecessary laws just die off" Wish Pilliod would.

I don't think wishing for a politicians death is warranted, if fact it's disturbing. I wish for these boneheads to be tossed out of office, but wishing for their death lowers you to their level.

In our system, we elect a few mistakes, you just have to wait them out. It's what seperates us from the crazies.

I think it was a tounge and cheak comment. I highly doubt he is wishing for a demise of an individual.

I agree, except we only have to wait them out about another 6 months and the political landscape could be extremely different then what we see today.

one can hope....
 

From your mouth (err...fingers?) to God's ears (err...eyes?)....

Hey come on now... I didn't say it, just helping a friend out.. LOL :D:laugh::D

sorry, I just took Belmont a little too literally. I just flashed back to all the "Kill B#sh" signs.

sorry
 

I did not mean literally. Unfortunately the town of Belmont has a lot of shortcomings and he is one of them. Over the years I’ve learned that not many of the elected officials in the town Belmont have much backbone. Years ago we went thru a subdivision and found this out first hand. Also had problems with a neighbor and that’s where it really became clear.
I honestly thought they needed to consult someone else before wiping their #$%%.
To bad, we have a great piece of property but will probably elect to build our new home elsewhere in the area.

A Little Help With the Math, Please...
 

I don't understand this. :confused:

NH Legislators grabbed $700K from the MP budget, but had earlier approved a near-doubling of 2010 boat-registration fees: even if registration fees only produced $12 for each registered boat—as a very conservative example—there are over 90,000 boats that can be expected to register!

(So over $1 Million would have been collected—leaving a net gain in MP funding). :confused:

APS, I had read a statement detailing the MP budget. Let me see if my old mind can remember the gist of it.

Apparently, they had a fund that was growing a little bit for a rainy day. The annual budgets, combined with decreasing registrations, had slowly eroded the fund. In addition, costs have steadily risen. The MP has had cutbacks and a decline in personnel as a result. So while they have doubled the fees, they have effectively taken that amount out of the equation.

$3 million budget, less half funded by CG. $1.5 million is the balance, which has been subsidized by the fund balance, which was in decline. They take $700,000, roughly half. So nope, not an increase. The registration increase was supported because of the MP's statement that costs were outstripping their funds. The Legislature had increased their costs, so it was only fair.

In the end, the registration increase became a general fund tax that boater's pay. The MP loses, at least this year.

Ticket on 89
 

I was driving the ol' Jeep down 89 from Burlington VT Friday. It was fairly straight stretch in Andover, NH. With the cruise control set at 74 on my Garmin NUVI 225, the Jeep speedometer says 77,78 mph. Local Andover cruiser stopped me and clocked me at 82 mph! So the GPS was off 8 mph!

Garmin claims .1 mph accuracy. I was traveling in a straight line. I'm wondering if the radar could be inaccurate. It was an one of those dashboard mounted units and he was parked in the median.

I wonder how they check the accuracy of police radar as I am sceptical of an 8 mph difference. How would you know if the LEO is telling the truth?

Last Time I Traveled I-89...
 

The speed limit was 65 miles an hour, excluding off ramps of course. So admittedly, on my part, if they allowed say 70 MPH in some sections, I have found that if you keep it under 5 MPH over the speed limit, and weather and traffic conditions pemiting, they usually won't bother you. However, there IS a fine line there, and you don't want to take any chances! Especially in this economy! They are out there writing up what they can, for job security, as well...

Should you go to court to fight the ticket, don't tell the Judge what you just told us... Wise...
Good luck...

38 -48 foot cruisers.

Used late 1990's-mid 2000's models go for: $160,000 - $525,000.

I gotta say, that's way out of my league.

If your work schedule allows you the opportunity, contest it. You really stand no chance against a speeding ticket as a valid RADAR certificate for the officer training and his equipment means his word against yours. It's a civil offense so there's no reasonable doubt criteria. BUT, you can hope he doesn't show.

Buy a radar detector. It stops you from casually driving along and getting a needless ticket.

Radar, both dash mounted and handheld, are supposed to be calibrated by a TMDE company once per year. We have a company come out and do it officially. We are also supposed to check the calibration with tuning forks often. You strike the tuning fork and the vibration simulates pre-determined speeds (for us it is 35 mph and 65 mph, we have two forks) there should be a stamp or sticker on each radar and the dept should be able to provide proof of date and time of calibration. This may not be possible at the initial hearing but there may be an appeal process to a judge (this is the case in Mass). Its a shot in the dark but if plan a doesn't work (officer doesn't show up) maybe plan b will work (out of calibration). If both fail, throwing yourself at the mercy of the court will sometimes work if your driving record is otherwise flawless and you are respectful...and the stars line up...

Good luck with the radar detector angle... I will put my radar skills against your detector any day of the week (playfully ofcourse). I have never given a break to a speeder that has a radar detector on the dash....
Secret- radar isnt sending out waves until I see you and push the button. Once that happens- BAM! your speeding and your caught (unless you can bleed 10+ mph in a milisecond or I blink,lol)

Good luck on the ticket
HCG

I heard the costs to get those tuning forks retrieved when they fell down the defroster slots was a big one :laugh:

Ever lose one?

If you paint any vehicle in front of me with lasar or radar you can't hide. My RD is one of, if not the best, on the market. Very sensitive. I sniff out the Maine State Police with ease and they go to great lengths to hide on bridge overpasses, on entrance ramps, etc.

As with any radar or lasar, if you are the only car on the road then you're vulnerable to getting a ticket if you're speeding. Also, if I was to get pulled over my detector would be out of site from your view and mine also has VG-2 immunity ;)

Some of us are serious tech geeks:D

Most of you are just speeders who tailgate and will someday end up in an accident. Don't know why people are in such a hurry to get places.

Very good points RailroadJoe!

Radar detectors are popular gadgets among speedsters who derive thrill from bending the rules and eluding the radar guns of the police.

Some people are not satisfied with moderate speed while driving. They want to be the fastest driver on the road as well as get to the places they're going in record time; they want to be always in the race.

IMHO anyone that has radar detection equipment in their vehicle and gets into an accident that can be attributed to high speed should be penalized the same as someone who Drives Under the Influence (DUI).

Here are some of the states that deem radar detectors illegal:

1. The usage of radar detectors are prohibited in the Commonwealth of Virginia. They have
laws banning the use of radar detectors. Not only are radar detectors illegal to use in Virginia,
they are also illegal to have in the vehicle.

2. Radar detectors and radar jammers are illegal in the District of Columbia. The passing of
their laws to ban the use of radar detectors was set in 1995.

3. In Illinois, radar detectors are only regulated in commercial vehicles of over 26,001 pounds.

4. On US military bases, they are legal to have but illegal to use.

5. Radar jammers are illegal in the states of Utah, California, Oklahoma, Colorado and
Nebraska.

6. Radar detectors are not specifically regulated, but things hanging from windshields are not
permitted in the state of Minnesota.

7. For motor vehicles over 18,000 pounds and any other commercial motor vehicles over
10,000 pounds in New York, radar detectors are illegal.

And you would be wrong. Sorry

I don't have to drive that much anymore but I have in the past been a long distance commuter. Trust me when I tell you that the odds of the day you drift up in speed to 75-80 MPH it's nice to have a radar detector bleep at you so you avoid the stray ticket. It's not some extreme desire to play race car driver. I can assure you some many of the lakes region long distance commuters who may read this will understand how easy it is to have a speed zone change and bam, ticket.

And the states LOVE speeding as they generate revenue out the fines they collect and the cops use it as a way to justify their expenses. Without speeding tickets your police departments would probably have less officers and less equipment. You should thank them;)

It seems there are a lot of cars being towed that have extensive front end damage. Tailgating ? Or just not paying attention.

That's funny reading that. Have you driven (err, sat) in rush hour traffic in DC and Northern VA, you can't speed if you wanted too:laugh:

Use of a radar detector to a DUI? Hint: Look at how many cars on the road have radar detectors.

The rules aren't bent. Speed and you can still get a ticket. You also don't elude radar. The detector simply tells you that radar (or lasar) is present. If you are the only car on the road, the detector may be a ticket indicator.....

And by the way, I haven't looked into radar jamming in detail but even if that act was not illegal, the jamming transmitter would in all likelihood be illegal via the FCC. Again, I haven't researched it but I'm betting that jamming is illegal because of something other than a state law.

You are so right RailroadJoe; tailgating is an epidemic on all highways.

Here is a short video that shows how speed kills:

<iframe title="YouTube video player" width="480" height="390" src="http://www.youtube.com/embed/_z8Mnf22D30" frameborder="0" allowfullscreen></iframe>

Rusty, last time I checked cars drive down the road with the front end pointed forward..... May be just a coincidence that cars in accidents typically have damage to the front end:rolleye2:

original topic
 

I find the technology part of the gps vs speedometer readings discussion interesting. I don't have a gps and never looked into how they work, cool stuff. I have compared one boat speedometer to another and have seen a difference. Whether you swap yours out for a new one or a friend clocks you, always a few mph off in my experience.

As far as getting ticketed in a boat, if the marine patrol handle it like they do on the roads, (not sure they do/will) the slightly different numbers may not matter. As my experience tells me that they tend not to pull you over for going 57 in a 55, although they could and maybe someone here will tell me they have, but I am not sure 60 in a 55 gets you a ticket most of the time either. Don't really know what the line is, but it seems there is some leeway there on the roads. I would think the same would apply for boats.

BH, not sure if you had other cars around but if you are doing 75-78 MPH that seems to be about the flow of traffic. Once you hit the 80+ MPH point is when you are basically passing most cars on the road. Kinda of a crude way to look at it.

As far as my Garmin GPS (Nuvi 2xx series), it seems to match quite well to my speedometer in all my vehicles. But I also run OEM tires.

Does your vehicle has the STOCK tire sizes and STOCK rear gears? Change either one of those and your speedometer (or speed sensor gear) will require changing. Changing from say a 255 to a 265 tires and or vice versa and you can get a different reading. There's converter tables out there to tell you the different speedometer readings.

Changing to a smaller tire is a cheating way to get more gearing in your rear-end (well, your vehicles anyway)......

Rusty, I changed my avatar just for you :laugh:

This one would be more appropriate for you:

http://imgs.xkcd.com/comics/duty_calls.png

You're catching on. I like it!

So is this an admission that you're wrong?

in conclusion
 

Traffic was sparse at the time. I was not passing nor were there cars passing. The weather was sunny and cool. The road was dry. I was driving reasonable and prudent at the time.

I have stock tires and the drive train is stock. I was told stock speedometers can be off by a mph or two. Mine was off by at least 3 mph.

Talked to a buddy of mine who is a captain on the Nashua Police department. As far as contesting the ticket. I was already 9 mph over the speed limit. Since the radar says you are over the sl by 17 mph, it would be tough to contest. It will be a slim chance I could get out of it. If the officer doesn't show up or can not provide a certificate of qualification and or radar does not have a recent certificate. In small towns it is possible, as some small towns have a very small staff and will not contest minor violations in court. There are rare occasions when a small town do not have certified officers or radar. Very rare.
If I was going 64 in a 65 zone. An officer pulls me over going 72. I am going 7 mph over the sl, a sympathetic judge may let me off with a warning. If I keep the preceding business like and not get into arguments etc. Very rarely would an officer pull you over going less then 10 mph over the speed limit if it was reasonable and prudent at the time. It is tough to prove if one is speeding when he is over by less than 5 mph. Radar do not take into consideration traveling around corners and sometimes weather can interfere with the signal. As far as the difference between radar speed and GPS speed, you need all kinds of expert testimonies to contest it. If you do win, then it could be an example for future cases.

I don't have radar detector or jammer. I use to work for a defense electronic firm. The engineers says radar detectors are not quick enough to detect the hand held. The dash mounts are on continuously and can be detected. Some of the engineers created home made jammers that hitch to a radar detector send out a signal at the sign of detection. If the detector is smart enough to detect the frequency so does the jammer. Some LEO says jammers are illegal because FCC regulate transmitters. The jammers and radar detectors operate on a frequency not regulated by the FCC. It is a mute argument.

My argument is what do we need to use in a boat to make sure we are with the law. Boat speedometers known to be inaccurate. According to my experience, one can not rely on a GPS speedometer.

Here smokey, smokey: http://www.escortradar.com/store/passport-9500ci.html

Also, some models in years past were taken off the market due to the FCC so they defintely have a hand in it. I will tell you that my Escort Radar Detector is no joke. My wife was miffed when she saw the CC statement come in. Ever since I got that 73/65 ticket on the turnpike I said never again.......

I have friends with the Portsmouth and Greenland PDs and they would tell you first hand that my Escort works against their car based units. I honestly have not spent the time digging into vagaries of how it works but now I have renewed interest.

Let me add this, as reality-based, but not scientific testimony.

I have a Garmin 440 plus a Tom Tom for the car. I've used the Tom Tom in the car, and it was always within 1 mph or dead even with the car's speedometer. In the boat, the Tom Tom was almost always dead even with the Garmin, as well as my Navionics App display on my iPhone. They were all pretty much dead even, within 1 mph max variation.

I'd have to say with your variation, either your car's speedo is off, or your GPS is somewhat screwed up. My boat speedo is pretty much dead on accurate up until 40 -45 mph. In the early stages, up to 25 or so, the GPS reads higher than my boat speedo. At 55 mph GPS, my boat speedo is bouncing around 57 or so, up t 60. After that? Well there is no after that, that's the max :eek:

GPS vs Radar
 

I like to believe my GPS is giving me the accurate speed. I get the impression that either the police radar is off or the LEO is having a bad day. :(

Radar/LIDAR misunderstandings
 

Just so no one is confused I need to correct a few statements made here.

As with most handheld units, virtually all dash mounted cruiser radar units have the same "instant on" capability. This "instant on" cpability has been available for years and is used whether the officer is stationary or in moving radar mode (operating the radar while travelling).

Additionally all radar jamming devices that emit RF are regulated and prohibited by FCC regualtions. How? In order to emit the necessary RF energy to jam a police radar, the jammer would need to have what is known as FCC type acceptance. To operate without this acceptance is a federal offense. To date no such device has ever been submitted or approved for Type Acceptance, for obvious reasons. That said it is virtually impossible for a local officer to enforce federal FCC regulations. However, local communities or States are allowed to pass supplemental regulations that prohibit operation or possession of such devices, and that is why a number of State's have those regulations which are easily enforcable by local, county or state officials.

In addition everyone needs to remember that there are two very distinct types of handheld devices. The oldest is the RF emitting type that has been available for several decades. The newer devices are LIDAR units, commonly called "laser" units. These do not emit RF energy, but for a layman explanation use light energy. There are a number of vendors that claim they manufacture a "light based" jammer for LIDAR units. Since these jammers are mostly passive devices or emit no RF energy they are not regulated by the FCC. However, local and state authorities could prohibit these devices by local ordinance if they so desire.

As a State of NH certified traffic radar operator I had many years experience with all of these devices, and have repeatedly came across much of these misunderstandings, especially in Court.

Hope this helps clarify some of the misunderstandings in the post quoted. :)

Skip

Just a reminder...my professional estimation of your speed is more than enough to hold you to a ticket. If I point my radar/lidar at you and nothing shows up, and I "estimate" that you were traveling in excess of a posted speed limit, that is good enough to ticket you. Tried and true, this is established precedent in Ohio and has been adopted by many other states including Massachusetts (not sure about NH but they are usually ahead of us when it comes to pro-police law)

http://www.cleveland.com/open/index....l_estimat.html

With this in mind...I don't hate speeders enough to need this. Just an interesting factoid.

Good luck, btw, the good guys always win...eventually!
HCG

Probably be another very long thread as to which one of us is wearing the white hat...lol

Laser jamming devices are quite legal (except in California and Minnesota) as they emit light which is not regulated. I have one and they work quite well!! ;) Combine this with a top of the line radar detector and I have never received a speeding ticket for accidentally or unknowingly exceeding the maximum speed which is quite easy to do when you are on the road daily.

Dan

I think this is where people get the misconception that owning a radar detector means a desire to be a speed freak. For those of us that do/have put a lot of time on the road, they save you from that inadvertant creep up in speed at the same time a cop just happens to be clocking cars in the median.

What's really fun is when I pull over to the middle lane and then watch someone pass me and there's the police car waiting. Sometimes I point to people and they slow down others give me a strange look. The figure it out quickly.

My Escort 9500 does jam lasar. There are even independant studies that show that is has masked the cars speed from point blank range.

And as far as speed estimation, unless a car is going much faster than all others around it then you better have a good way to explain that. Some of us even have dash cameras too albeit mines a cheapy and the audio sucks. Like I said, some of us are tech junkies.

hancoveguy, I have to ask if you don't think that's a tad frightening? I can see an officer pulling over a car going excessively fast like 50-60 MPH in a 25 MPH zone or 90-100 MPH. And I would call that reckless driving or some other applicable offense. If you want to tell me that on a highway you can visually estimate my vehicle to be going 76 vs 65 MPH or something like that with repeatable accuracy then I will call you out on that. The whole point of the radar/lasar equipment is to provide an objective measurement. In my case, unless I am the only car on the road and you are using radar/lasar, I've detected you from several thousand feet out and have already slowed.

I am shocked that the court did not just toss the case if the guy was not certified using radar. I also believe this is an overzealous enforcement and the state makes sure they don't lose these cases or they risk losing all that revenue. And, that decision was not unamimous. I'd like to see a US supreme court ruling on this case.

If you think this is good for society for judges to give carte blanc discretion to an officer to guess a vehicle speed to issue a speeding ticket then I give you no credibility. Luckily this is probably rare and if an officer used this more than once I think it would raise flags about why he's not using the state supplied equipment. There are checks and balances.

Just goes to show the speed limits are not about safety but revenue. Makes me smile even more knowing the stuff I have in my truck. Gives power back to the people:D

What gets me is that the police officer estimated by eye that the SUV was going 73 mph and that radar gun read 82 or 83. Wouldn’t that tell the Supreme court as well as the lower courts that there is a discrepancy about how close the officer can estimate speed? Granted he wasn’t certified to use radar but it should have been enough IMHO to throw the case out. If he can’t estimate within 10 mph then this case went way too far in the courts.

The case alludes to this being valid only if the officer is trained and certified in estimation. This is a substantial instructional block in every academy that I know of in Mass. This estimation principle, if you will, is mostly used in an unforseeable scenerio. You will not find officers setting up on a stationary traffic enforcement assignement armed only with their estimation skills. The prime example of how this is used-

You are on patrol in your cruiser. You are stopped, waiting to pull out from a sidestreet or strip mall or something like that. Your dashmounted radar is facing straight forward and straight back (perpendicular to the traffic flow) so it is useless on short (immediate) notice. You have no handheld with you. Now, you have travelled this road hourly for most of your adult life and you know and are comfortable with what the traffic flow looks like at any given hour. Just then, from around a distant corner, you see a smaller car headed towards you. Based on all your experience and training (nevermind as a police officer, just as an alert motorist) you know beyond all reasonable doubt in your mind that this vehicle is travelling well in excess of the posted speed limit of X. This vehicle is travelling so fast that you believe it could eventually become a hazard to other motorists but not so fast that it is out of control.

What do you do?
A. Nothing, because you didnt get it on radar or laser and you clearly do not have enough to stop the vehicle on any foolish reckless driving violaions (which there is no such thing btw)
B. Unlawfully stop the vehicle and only verbally chastise the operator
C. "estimate" the vehicle's speed based on your inherent knowledge of the road and the traffic flow and cite the individual accordingly, knowing that even though you don't have 100% assurance of your estimation's accuracy but in the name of the public good, you are bound to "act" in some way.
D. shoot the person and go get coffee and donuts

This is truly not meant to provoke an argument but rather to illustrate the necessity of the law/policy. You are certainly entitled to your opinion, but this is reasonable in mine.

Disclaimer- As many of you know from my previous posts, I am not a big speed enforcement guy (or state revenue agent as it were) as this practice would make me a hypocrite, but there are some times when you just need to trust the system.
BTW- Lawn psycho, you are off track if you think the liberal courts in Mass give two flying hoots about revenue when it comes to tickets, appeals, or anything else within their judicial scope. I have seen sooooo many fines just eliminated for no good reason. They truly do not factor governmental revenue into justice. They are far more likely to find on behalf of the violator just to spite the police.

I would get him for the following which is in Ohio’s Chapter 4511,Trafficlaws-Operation of Motor Vehicles, Subsection 4511.20:

"4511.20 Operation in willful or wanton disregard of the safety of persons or property.
(A) No person shall operate a vehicle, trackless trolley, or streetcar on any street or highway in willful or wanton disregard of the safety of persons or property.
(B) Except as otherwise provided in this division, whoever violates this section is guilty of a minor misdemeanor. If, within one year of the offense, the offender previously has been convicted of or pleaded guilty to one predicate motor vehicle or traffic offense, whoever violates this section is guilty of a misdemeanor of the fourth degree. If, within one year of the offense, the offender previously has been convicted of two or more predicate motor vehicle or traffic offenses, whoever violates this section is guilty of a misdemeanor of the third degree.
Effective Date: 01-01-2004"

Thats excellent but what is your basis for "willful or wanton disregard" if you can't "estimate" that what they are doing is willfully and wontonly disregarding public safety etc....Is there an objective "brightline" standard for willful and wanton? And if so, without estimating that they are speeding, how do you satisfy the criteria?

Also, you cited a criminal statute not a traffic infraction. Just so I understand this... its not okay to issue a speeding ticket (non criminal infraction) based on estimation only but you can summons someone into court or arrest, (both will give someone a criminal record) based on an estimation?

I am clearly not following your logic, make me understand plz.

HCG

You asked: “What do you do?”

So I looked up the Traffic laws for the Operation of Motor Vehicles in Ohio and found that section. I guess I was wrong.

I just think that estimating speed by eye shouldn’t hold up in court. If you can’t use a radar gun because you aren’t certified then you shouldn’t be out on patrol for that reason. Stop the vehicle and give him a warning and then get yourself certified to use a radar gun.

Rusty, I am really not trying to argue with you and I apologize if my previous post looked sarcastic or disrespectful. Was not my intention. Some people just don't understand that without the estimation rule,( and a few other discretionary allowances of L/E) you would have no legal grounds to stop the vehicle and even warn him. I agree with you 100% about an officer's lack of certification. If you cant maintain certification, stay home. But the scenario I gave you is real and I assure you it happens all the time. Just to expand a bit more on it. Lets say you estimate and when you pull the car over the person...was drunk or just robbed a bank or just smacked his wife around or just committed any crime. Without the estimation rule, you have no grounds to stop the vehicle. If you stop it anyway, anything you discover ie drunk, car full of money from bank robbery, bloody knuckles from domestic A&B etc... all of this is 100% inadmissable in court. In other words, because the evidence was obtained without probable cause for the stop, the evidence is lawfully excluded from trial (wong sun- fruit of poisonous tree doctrine).

Its a balancing test-
The rights of persons to be secure from illegal search and siezure (4th amd)
vs
The rights of the police to make reasonable attempts to ensure the safety of the motoring public.

Worst case- someone is unlawfully (but not maliciously) given a non criminal traffic fine
Best case- complete motoring anarchy is prevented (slight hyperbole)


Respectfully
HCG

HCG, the issue with how you losely throw around a traffic citation is you discount the days of background checks and the internet.

Get a secret/top secret security clearance for the Fed Gov and EVERY ticket and hangnail you ever had needs to be revealed. Those tickets also have an impact on your insurance rates.

I was run over by an SUV while riding my bike. During the disposition my driving record, the # of hairs on my head, you name it was put on the table for the drivers insurance company to see.

Speeding ticket fines are nothing. That's why people speed. Make the punishment or fine harsh/high enough and it would be nearly eradicated. But, just like DUI, it's an industry that generates money.

Also, giving cops a loose leash to stop for any reason isn't reasonale either. When I was in the Navy and 19 yo my best friend and I spent 2 weeks in Florida. While driving home as we passed into GA, I was doing exactly the speed limit. Getting a ticket while in the Navy nuclear power program with a submarine designation could get you adminstratively dropped from the program on personal conduct grounds. I was driving a Ford Taurus and it was 2 or 3 AM. Out of nowhere a state trooper pulled us over . Apparently 2 white males in a basic 4-door sedan doing the speed limit in the middle of the night on I-95 fit the drug running profile. When he stopped us, he asked where we were going. I told him VA. He then asked us to step out of the car and had us put our hands on the hood while he was radioing in my license. I also handed him my military ID which didn't seem to impress him. During that time he asked if he could search my car and I made the mistake of asking "why" instead of "go ahead". My friend then had the wits to ask why he stopped us. He said my license plate light was out. We go to the back of the car and it was on:rolleye1:

About 45 minutes on the side of the road and having a drug dog search the car we were let go.

I have a jaded view of how police conduct business so I'm not cutting you even 0.0000001% slack. My rights and the constitution mean something to me and your post above seems like you're willing to bend them. Of course being a cop, I'm not surprised.

Interesting Article
 

Relevant on a few levels....

http://www.cnbc.com/id/41621788

I like the cops face at the end of the video:
http://www.youtube.com/watch?v=VTJwx...layer_embedded

Okay, it appears one of us is a bit too bitter from way back. My involvement in this post was on a novelty level, maybe I could shed some light on the way some things are done from a perfectly legal law enforcement stand point. I believe I even used the word "playfully." You apparently are a bit more emotionally involved in this issue than I care to devote the energy required to defend my position. I guarantee you my respect and knowledge of "our" constitution is at least equal to yours if not better (several pedigrees to back this up). You clearly dislike the police in general and are hiding behind "your" constitutional rights to justify this vitriol.

For your benefit, I will refrain from any further comments, posts or threads that may purport to force my overzealous, "big brother," unconstitutionality on the forum's readers. I will limit my posts to regaling the readers with stories of when I was in the service and my rights were violated and offer short stories involving me being the perpetual victim.

My apologies to anyone else I may have offended,
HCG

BTW, I truly hope you realize that this video is fiction produced by your radar detector company for the sole purpose of selling their products.

Hancoveguy;

I for one find your posts most informative, honest and respectful. I truly hope you will continue to post as you have and not change your ways because of one or two disagreeing posts.

Be proud of how you serve the community! I thank you for it!

Respectfully;

Dan

Hancoveguy,

I think you have done an outstanding job with all of your comments concerning this threads topic. I asked you questions and IMHO you gave me honest and well thought out answers.

Thank you for your service to our great country and also for being a member of law enforcement who do such a great job to protect our communities.

If I have said something that offended you in anyway then I apologize.

Rusty

Do ya think?

I agree wholeheartedly with Dan & Rusty.

Hancoveguy has been a very thoughtful poster that has shared many of his experiences and expertise in a variety of posts....posts that, to me, make this site worth perusing everyday.

Don't let a differing opinion or bias against law enforcement chase you away. That has happened all to often on here over the years I've been involved. I have seen several NHMP personnel and other law enforcement types come aboard, try to explain the law, only to be chased away over time by a very small percentage of the members here.

It is too bad, especially in the case of both a retired and an active NHMP officer that posted here in the past. The great majority of us lose a tremendous resource because of the actions of but a few that made them decide the foolishness wasn't worth the effort.

Don't get me wrong. Just as in any profession there are always a few rotten apples and plenty of stories of horror amongst the public that may have had a negative experience in the past.

But to personalize this angst against a fellow poster who has no connections to far ago alleged incidents is not fair to that poster, nor the rest of us that may lose a valuable resource in the end.

Hang in their Hancoveguy...we need more posters like you, not less! :)

HCG, I just so happen to have a relative how owns a seacoast business that is frequented by a large number of Seacoast PDs. I know more than a handful on a personal level. I don't dislike the police in general but know some officiers who I don't believe should be allowed to wear badges. I'm sure you know some of them. At least based on your previous posts I didn't think you fit that category until I saw the what appears to be an acceptance of 'blurring' reasons to stop someone and I understand the tough position cops are placed in when it seems the crooks have the upper-hand.

I've told this story to other officers over the years and nearly everyone of them comes up with a justification for it and many like yourself tend to use an "end justifies the means argument."

It happened to me and I'm sure it's happened again to someone else. That's unfortunate as it was a humilating/scary experience for a 19 yo old impressionable kid which I was at the time.

Garmin tech
 

Talked to someone at Garmin about the radar - garmin discrepency. They say both devices should be dead on. They are willing to be expert testimony on the validity of the GPS. If the courts don't believe the accuracy of the GPS, that would put the GPS system in a nutshell.

If I had unplug the Garmin right after the stop, they may be able to hack the memory and show the court my accurate speed. next time I know better. The date and time will be stamped.

I still say the officer had a bad day and made my day.

Twice in my life, I was picked up for DUI and had my day in court. I am profound hard of hearing and my speech is not good. I have bad equilibrium and I can not walk a straight line. I was giving the breathalyzer and I pass. Yet, the officers insist I was onto something and arrested me. Both times I was found guilty in, what my lawyer says, 'kangaroo court'. Yet both officers failed to appear in appeals court. So the convictions were thrown out. I lost my license for 30 days even though I was innocent. Is that justice? Since then, I hate to be driving around at night.

Next time I get caught speeding, I'm saving my GPS memory.

Thank you Skip, Rusty and Dan (Ishoot), for the kind words. I really enjoy this forum and will continue to post (thank you for the priviledge). I did attempt to agree to disagree but I stooped and took the bait. Shame on me, lol.

I am renewed and refreshed and can't wait til ice out...
Bring on the boating season!!!


HCG

Would those include any of officers in the NH Marine Patrol?

I don't know any NHMP officers nor have I ever been stopped, etc so that would be no. NHMP is probably a different scenario as many of them are seasonal and serve a slightly different clientele (boaters) where parking 149 ft from shore in a NRZ is reason to turn on the lights and politely asking people to move. The para-military type officers probably aren't satisfied with that type of duty;)

Took the bait? I guess someone else typed those words for you that giving tickets and pulling people over for virtually any reason based on officer discretion is OK. Funny how the brotherhood and Skip was so quick to defend you. I stand 100% behind what I've posted and if you think you are taking some kind of high road, your posts above shows your character as an officer IMO.. The only "bait" appears to be the one's you pull over when you are on your next power trip.

"Brotherhood"???
 

L.P.

I guess I'll take the bait this time...By your term "brotherhood" are you alluding to the fact I am somehow involved with law enforcement?? If so, let me state for the record that I am not. I do not know nor have I ever met Hancoveguy. I merely stated that I have enjoyed his posts in the past and respect what he does for a living. You may not and that is your opinion.

Dan

I was referring to skip......

Lawn psycho, you make some good points but you went too far. Just like on the rafting thread.

I've had spirited discussions on this board with some of these guys. If you discuss things rationally they will respond in kind. You can learn a lot and make your point. Even if you never agree with someone, it is good to see why they believe what they believe.