Police Radar

[Davepatrol]

When my speed reads 100kph, the gps says 98kph.
So hopefully I wont see Radar.

Jon,
 When your speed reads 100kph You would have to be going down a pretty big hill

[Rumpig]

When I set my speed by the GPS I'm surprised at the number of cars that are travelling slower on the highway.

i notice that all the time when sitting on 100 - 110kph, people regularly give me dirty looks as i overtake them on dual lane carraige ways when towing with the camper on the back, but they are actually sitting under the limit yet their speedos would be saying they're doing the speed limit. i know the wifes car shows 97kph when my GPS says 100kph, so i can't blame them for thinking i'm speeding, but i'm not.

[SteveandViv]

Yea we also have errors in our works cars like all have said - our Paj is spot n though with two GPS's we have. I use my GPS and I know that right cause when I got pulled up between Fiztroy and Halls creek for doing 132 in a 110 zone both myself and to copper agreed. Anyway was a good bloke and let me off as we were on a mission to Balgo after storms knocked the clinic out. He did ask me to slow down a bit though 

Stupid speed limit up her with the roads so good and empty. At this time of the year there are so few cars we really don't worry as you can see a car in the distance and be down to speed before your able to get pinged. Not so the dry season, they his behind the caravans.

[SambOz]

Yep, I realised my error and edited my post two minutes before you replied 

They are calibrated every year and checked every shift

 

[briann532]

i notice that all the time when sitting on 100 - 110kph, people regularly give me dirty looks as i overtake them on dual lane carraige ways when towing with the camper on the back, but they are actually sitting under the limit yet their speedos would be saying they're doing the speed limit. i know the wifes car shows 97kph when my GPS says 100kph, so i can't blame them for thinking i'm speeding, but i'm not.

Yep, I cop that all the time, my speedo at 110kph on gps says I'm doing 103.
I get some rude looks too.

I have 2 x gps's and have compared with the phone gps and all are spot on 110 at the same time, so I'd trust them over the speedo......

Brian

[Murph]

Mine is out 10% and by the looks of the people I pass I'm not alone !!! Lol!

[jclures]

My son and I are working on a WB holden ute, and we are looking at one of these for the speedo, it has a few nice features and it is only using the gps.
http://www.speedhut.com/customizer.i?clid=1540805

[Bunyip]

I used to work for a cab company in Sydney and whilst GPS is great I would not rely entirely on it. The number of times we had to do a track on a taxi and the GPS said it was in the middle of Sydney Harbour, or off the heads somewhere was surprising.

The taxis had what I would consider to be above average fixed GPS units in them as well.

Bunyip

[4wd26]

^^^ in a city you can get "bounce" of the satellite signal, causing a "delay" and then the calculation is incorrect, especially as the visible sky is limited by skyscrapers, leading to less redundant calculations being possible.

I did some calculations on this quite a few years ago

basically the spedo will be more accurate (more calculations per second- relative to the tyre rotations), BUT has a inbuilt error/ margin

The GPS speed is calculated on where you were, and updated every second, the update rate can sometimes be worse than that.

So if you know the error in the speedo and correct for that, that will provide a "more correct" instantaneous speed.


but due to reaction time and digital readout GPS will be adequate


But will not stack up in court for defence 

[Turbojohn]

Can anyone tell me what the range is on these? I would be keen to know

[treads]

Can anyone tell me what the range is on these? I would be keen to know

About a kilometre on a straight bit of road with the Stalker Dual DSR in moving mode.

Furthest I've got with the Pro Laser III is 1.9k's on the back of a B-Double

[fuji]

The new toy of choise seem to be Number Plate Recognition . l saw it in action on the Hume South bound at Broadford last week . The beam scans the plate & budda bing , budda boom it spits out   a list of all the things the owner of the car has out standing . Then a nice man with pale blue shirt & a Glock will ask you some questions , & may invite you to pop back to the Poilce station with him . There were 5 cars parked on the side of the road & a tilt tray was loading up . Some there had a good day out others didn't 

It spits out information in relation to your vehicle or licence status. We don't us Glocks, only S&W 40 cal. We now wear dark blue shirts. Well some still have the lighter blue shirts.

[Bird]

[fuji]

About a kilometre on a straight bit of road with the Stalker Dual DSR in moving mode.

Furthest I've got with the Pro Laser III is 1.9k's on the back of a B-Double

Played with the new PL lV yet?  Very noice. Had a play with it at RES

[Pipeliner]

The point was made earlier (in passing) that your speedo is designed NEVER to over-read (it doesn't comply with the ADR otherwise) which taking into account the manufacturing tolerances means that it usually under-reads BUT this assumes that your tyres are the same size as were fitted by the factory.  If you have increased your tyre size (and most of us probably have) then your speedo may well be over-reading.

If this is the case it is worth seeing if your dealer can recalibrate the speedo to match your tyres - since most speedos these days are electronic (except the ones Tony Abbott wears) this is usually just a quick computer fix.  In the meantime use the GPS speed.

[Spada]

I'm just about sick of the auto numberplate reading thing.

My father has given back his licence on medical grounds, but still has his car registered in his name so I can use it to run him around.

Dammed number plate reading thing that the police use keeps flagging his car as having an un-licenced driver, and I keep getting pulled over for a "random" licence check.

[Turbojohn]

About a kilometre on a straight bit of road with the Stalker Dual DSR in moving mode.

Furthest I've got with the Pro Laser III is 1.9k's on the back of a B-Double

Thanks Treads, that's way further than I would have expected! By the time you see them its too late. Good thing I don't speed then 

[Mallory Black]

We have a Tom Tom in the Prado and it's pretty fast with it's calcs on road speed, plus it has the speed zone overspeed alert which is really helpful.
We have an older Garmin in the Mazdarati and it's really slow in calculating car speed, so we don't really trust it unless on the highway

[sol]

So what happens when there's a car doing say 115ks in a 100 zone and behind him is 3 or 4 other cars  keeping up him, does the radar read their speeds as well?

     

[Mallory Black]

hope so Sol, I wouldn't want to be takin one for the team

[treads]

So what happens when there's a car doing say 115ks in a 100 zone and behind him is 3 or 4 other cars  keeping up him, does the radar read their speeds as well?

     

There's a lot of variables in that scenario; but mostly to do with how far back the other cars are. Generally if the radar is giving clear tone and only has one display lit (Target), then the biggest (closest) target is the fastest. Generally it's proven by using a combination of methods by the operator, such as passing the first car and watching the displays for changes in readings. That's a pretty simple version of a complex operation.

[Jeepers Creepers]

A few years ago (living in Brisbane then), four of us went for a bike ride out to Artula for a pub lunch.

Stuffed our faces, had a light beer each and someone suggested a quick blat up to the top of the gap and back.
So off we go and in a few KLM's, we're joined by another rider.

The five of us ripped it up the gap at 10/10ths having a grand ol time.
About half way towards Warwick from the gap, Constable Dibble goes past the opposite way, flicks on the flashing lights, rips a u-turn and comes after us.
We were gunna turn around shortly anyway, so over to the side the 4 of us pull up.

The bloke we didn't know, turned up the wick and kept going.

The cop pulls up and screams through his passenger window, is he with you guys?
My best mate goes, yeah, but you won't catch him.

He screams, you 4 stay here, i'll get him and bring him back in a minute.

So the ol cop commodore fangs off after him and the moment we couldn't see him, we ripped off a u-turn and headed for home.

Never heard from the Mr Plod and life went on. 

[Hairs]

Jon,
 When your speed reads 100kph You would have to be going down a pretty big hill

Oh you can be a funny bugger at times Dave   

 

[pauljygrant]

My new Navara with obviously new and correctly sized tyres has the speedo hugely out compared to the GPS. At 100 kmh on the GPS, my speedo reads 108.
( the same GPS unit with my old Pathfinder, with factory sized tyres was much closer to the speedo reading, approx 100 on GPS and 103 on speedo).
Is this a strategy by the manufacturer to increase revenue from more frequent servicing.  If the cars speedo is over reading by 8% then I have to get it serviced 8% more frequently etc.  it also depreciates quicker since appears to have bern driven further.  Further, the warranty runs out quicker if distance based upper limit applies before time limit.  8% additional servicing revenue for every car sold and under manufacturers warranty must earn the manufacturers and their dealers a nice profit!
Paul

[Jasjul]

I don't know about Nissan, but my new Mazda BT50 with standard size tyres, the odometer was spot on, but the speedo was low.  Maybe Nissan do the same thing.  Manufacturers just make the speedos read low so that they can't be blamed by the public for speeding fines.