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In other words, if you're caught speeding, tough. Don't do it.

Speed cameras, motorways

Just thought you'd like to know a little information from someone who does work for the Met Highway Division they've just finished installing 60 (yes 60!) new digital ISDN cameras on the M25 between the M40 Junc (16 I think) and the M3 Junc (12) These babies have no film and send the pics down a wire to a central system which can have a speeding ticket printed within half an hour. Unfortunately no info on the speeds at which these cameras are set to fire. You have been warned.

A bit more info on the speed cameras The cameras are due to be operational by the end of the month They'll be set to speed limit +10% + 3 mph, and will mainly work when the variable speed limit is in operation on this section of M25 So, 60 mph limit and they'll go off at 69 mph They're not supposed to be working when the limit is 70 mph, but I wouldn't trust the bastards. You can spot where the cameras are - there's a 10 ft aerial by each one on the gantry's.

A little more info on the new speed traps (M25, M1, M20)

New Type of Speed Cameras on M1 & M20

Speedcheck SVVD or SPECS went online last weekend on the M1, netting 4,300 offenders in a single day. The system does not use instantaneous speed like the cameras we're all familiar with, instead measuring the average speed of every vehicle over a distance of about a mile. How? By reading your license plates and matching them up camera-to-camera.

Kent and Leicestershire police are so impressed with it that systems are being erected in their enforcement areas too. This is a new system which has now entered service after successful trials on the M1 and M20 in the UK. Speedcheck SVDD (Sureway Video Detection Device) is a system similar in concept to the GATSO, but with a new twist. SVDD deploys cameras at either end of a measured baseline (up to 500 metres) to monitor vehicles 24 hours a day.

Using machine vision, vehicle numberplates are read, and the precise time of each observation recorded and as a vehicle passes the second camera, the numberplate records are matched, and an average speed for the vehicle is calculated. If this is above the trigger speed, then the vehicle's identification is recorded along with it's speed. It is also flashed up on a huge illuminated sign further down the road to embarrass the driver into slowing down. When triggered, the detection technology used in these cameras automatically records the date, precise time, location and speed of the offending vehicle, along with a full colour image of the front of the vehicle, which clearly records the numberplate, make, model and colour of vehicle.

There's five overriding reasons for the habitual speeded to be afraid of this system: It works 24 hours a day, needs no film, uses no flash, and uses no radar... so bad luck all those of you who think that radar detectors work. It's been proven to be over 99% accurate in almost all weather conditions. It doesn't do spot-speed checking. A GATSO can only check the speed of a vehicle within a certain range so the tactic most drivers use now is to slow down for the camera and then speed up again once past it. Speedcheck measures average speed over a known distance. So if you do 60mph under each camera and then speed up to 80mph in between, your average speed is likely to be near 70mph - 10 over the limit imposed - you're nicked. SVDD say this means that the system can impose a far smoother flow of traffic eliminating slow-fast driving that GATSO cameras provoke.

Because it's automated, the system is entirely self-sufficient. It's hooked up to the DVLA computers, and can automatically process the fines and send out notices in the post. It's Big Brother. Don't believe for a moment that this technology will only be used to catch speeders. It could eventually be used to keep track of where every single car in the country is at any given moment in time once the network of these things becomes broad enough.

Warning to M25 Motorists

Apparently, there are 60 cameras that started operating on the M25 on Monday 14 June 1999. These are between the A3 and M40. They are digital and linked direct to computer, use no film or flashgun. They can deal with 60,000 tickets every hour. The cameras are also (apparently) linked and can work out your average speed between them. So, if you speed up between them and slow down as you approach them, if your average speed is over the "legal limit+N%" threshold you may well get a ticket. See

Speed Camera Operation, Laser type

The laser is in fact an infra-red laser, else it may damage people eyes. It is pulsed at a high frequency, say 1kHz or more. The beam hits the car and generates a scattered reflection. Some of this reflection is picked up by the photo-receiver also on the camera unit. This is why they don't actually need to shine the laser onto a reflective surface like mini chrome grilles!
Infra-red can reflect off 'non-visibly-reflective' surfaces too.

The received pulses will be delayed by an amount proportional to the distance the car is away. The 'time shift' in the received pulses is the delay. Yes, light does travel at light speed, so the delay is small...only a few nano seconds, if that. This is no problem for modern electronics to detect. As the car approaches the camera, the distance decreases and hence the delay decreases too. The rate of delay-decrease is proportional to the speed. Bingo!

Requires a laser diode, photo-detector, phase-locked-loop and a few other components. Cost about 100 quid (70 of that is the laser diode). Size... matchbox. Incidentally, laser guided missiles work in a similar way. One aircraft shines a laser to the target, and another fires a missile which homes in on the reflection 'cone'. So, if you're strolling down the road and you see a big (about 5ft diameter) red circle on the floor, beware, you may be about to be 'taken out'.

Speed Camera Operation, Radar type

Ok, this is how I THINK they work. The 'radar' sensor looks down on the carriageway (one lane) and detects radar waves bouncing back at it. Normally none bounce back as the road is not face on to the sensor. When a car enters the scene the waves bounce back at the sender. If the car is moving, then the 'Doppler Effect' causes the received wavelength to stretch. This is why an approaching car/train sounds like "vvvvvvvvvvvvrooooooooooooooom" as it goes past. The sound is the same to the car, but is squashed then stretched to the onlooker's ear, as the car approaches and then goes away. The amount the wavelength is 'shifted' is directly proportional to the vehicles speed. This is how they tell if you're speeding or not, and this triggers the camera. Now, 99% of camera's have white graduations painted on the road sides too.

As a 'second opinion' the distance travelled by the car down the markings before the flash fires is another measure of your speed. A lot of cameras take two shots. One as you trigger the radar, and one at a set time after that. This clearly shows the distance travelled in a time, and then they can work out your speed. New laser cameras detect the time it takes for a laser beam to be reflected back to the camera. Radar and light are both electromagnetic waves, so they use very similar principles. Because the transmitted radar waves disperse as an expanding 'sphere' from the transmitter and then as another sphere from the car back again, this 'double inverse square' law means that you can detect a radar trap 4 times further away than it can detect you of course with equally sensitive receivers. That is why radar-trap-detectors DO work.
The radar bands used are the K, Ka and J <?> bands and are at 10,16 and 28 GHz <?>. IR is in the order of 850nm (0.35THz).

Speed traps, radar 'detector detectors' (I)

They get you with something called VG-2. All receivers, even your car radio and, for that matter, your computer, emit a certain amount of
radio frequency (RF) signal. The frequency varies, depending on the type of receiver. The cops have a device that homes in on the RF signal emitted by all radar detectors. Most of the newer detectors sold here in the US are designed to either jam VG-2 or at least let you know when the cops have locked in on you.

Speed traps, radar 'detector detectors' (II)

The detector detector is rather cunning, although detectors do emit some RF when they are not affected by a signal they emit another stronger signal when they are hit by a radar signal. So what good guns (and even apparently some of Gatso's) have built in is a device that looks for this signal so they can tell exactly which car is using the detector, ie the one in their sights. Otherwise they wouldn't be able to tell which car was using a detector in traffic.

Speed traps, radar 'detector detectors' (III)

They do give off some spurious energy which some radars have a detector built in for. Some manufacturers add a feature called VG-2 which is claimed to make them undetectable, but I have my doubts. My Uniden SWS 2500 gives off a couple of beeps when I pass another car with a detector so I get the feeling most do give off a little signal which can be picked up. The other thing is the case. A metal case would shield better then plastic.

Speed traps, radar 'detector detectors' (IV)

As mentioned in prev replies, a lot of radar detectors can be picked up by Police Radar. In NZ Police operate with the 'Hawk' doppler radar, and this will inform the operator when a car is using a radar detector. I know because I operate a Hawk on a daily basis. :-) I would also be very dubious about buying a detector to evade the new Laser Radars. The beam is so narrow that chances are if your detector is picking up the signal, then it's your car that it's being pointed at. Too Late!

Speed traps, radar 'detector detectors' (V)

Radar detectors (at least in the states) are detected with a VG-2 radar detector detector. Most new radar detectors have a built in radar detector detector detector (I know how stupid that sounds). When it detects the VG-2 radar detector detector it shuts down radar detection functions and warns you of this. This is often referred to on a detector as VG-2 immunity.

Speeding tickets (UK)

"What does a speeding tickets SP30 mean?"

The 30 is not the amount over the limit, it is a code.

SP30 Exceeding statutory speed limit on a public road
SP40 Exceeding passenger vehicle speed limit
SP50 Exceeding the speed limit on a motorway
SP60 Undefined speed limit offence

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Article on The Internet Mini Encyclopædia

Header SSI Insert revised (no index tag!): 22-Feb-2016

Find Mini on Amazon | Mini Books! | About the I.M.E. | click to bookmark this page (AOL click AOL Heart )

Letter Indexes.... A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z