How to tell if the Gatso is live...
How to tell if the Gatso is live...
A few facts about Gatso's......
First of all they only apply to vehicles travelling in the direction they are pointing, in other words if it flashes in your rear view mirror then you might be in trouble, if it flashes in your face you are OK.
If the camera does flash as you approach, it is telling you 2 things, firstly, you are speeding and secondly, there is no camera in the box.
This is because the flash and the speed detection device are permenantly fitted in the Gatso and are permenantly on. When there is no camera the sensor is in roaming mode, that is, it will pick up any vehicle in any direction that is travelling over the set speed.
When a camera is fitted it is in dedicated mode and will only monitor the measured area (that big ruler) on the road surface running away from the Gatso. It will ignore traffic coming toward the camera.
So, if you get pinged as you pass through a Gatso and can't wait the 14 days to see if there was a camera in the box just wait until someone is obviously speeding toward the camera and if it flashes you are home free, if it does not you are in trouble....simple.
This technique gets a bit tricky when there is a Gatso pointing in both directions!!
Either way there are many more Gatso's than there are camera's to put in them so all is not lost whatever happens.
First of all they only apply to vehicles travelling in the direction they are pointing, in other words if it flashes in your rear view mirror then you might be in trouble, if it flashes in your face you are OK.
If the camera does flash as you approach, it is telling you 2 things, firstly, you are speeding and secondly, there is no camera in the box.
This is because the flash and the speed detection device are permenantly fitted in the Gatso and are permenantly on. When there is no camera the sensor is in roaming mode, that is, it will pick up any vehicle in any direction that is travelling over the set speed.
When a camera is fitted it is in dedicated mode and will only monitor the measured area (that big ruler) on the road surface running away from the Gatso. It will ignore traffic coming toward the camera.
So, if you get pinged as you pass through a Gatso and can't wait the 14 days to see if there was a camera in the box just wait until someone is obviously speeding toward the camera and if it flashes you are home free, if it does not you are in trouble....simple.
This technique gets a bit tricky when there is a Gatso pointing in both directions!!
Either way there are many more Gatso's than there are camera's to put in them so all is not lost whatever happens.
- tony.wilde1
- Posts: 2230
- Joined: Thu Apr 10, 2003 9:32 pm
- Location: sussex
gatso.s
17ton scania trucks stop them working too..when in reverse




Ok, you asked:
Firstly, they have to measure your speed. This bit can be done in two ways. One way, by using piezo-electric strips embedded in the road; two such strips at a known distance apart will detect your wheels over them. The time it takes between the two strips gives the speed. (Speed equals distance divided by time.) Another way is to use radar. By emitting suitably high-frequency radio waves, they can bounce these from the vehicle, and the rate-of-change of distance is detected by a frequency shift from the reflection. If this rate-of-change is higher than the rate-of-change for the speed limit, you're caught
.
Next, they have to photograph the vehicle. This bit sounds easy but is not so straight-forward. The photographs taken will be both normal and infra-red. (The infra-red will 'see' your registration mark when the vehicle is caked in dirt.) Also, to collect the proof, two photographs are taken in quick succession, so that the distance travelled can be seen. Obviously the "quick succession" is a known time: Again speed can be calculated. To determine the distance, white square marks are usually painted in the gutter of the road and again on the crown of the road. These are a known distance and the two photographs will show the distance travelled.
How do we avoid getting done????
Again, in order. If there are piezo-electric strips, there is nothing practicable that can be done
. Radar on the other hand is quite easy to fix.
For the boffs amongst you, current technology uses X Band radar (which is really microwaves). The frequency is about 10 Gigahertz, which (take it from me) yields about a 30 hertz frequency shift for every one-mile-per-hour travelled. If you are travelling towards the source, the frequency is added (and goes up) and goes down if you are moving away by the same amount. 30mph gives a bit over 900 hertz shift. If another (similar) radar source were to mix its frequencies with the reflected ones from the camera, you would confuse the living daylights out of it. It might record your speed as something very erratic and probably impossible! It also shows that these cameras can photo objects coming towards them as well as going from them. It would strike me that either the camera has the facility to photograph the oncoming and departing vehicle, or the police can alter the angle of the camera and focus it on either side of the road
.
The photography bit would be interesting, too. For the infra-red part - simply drill some small holes in the vehicle registration plate to take infra-red emitting diodes. A number of them permanently emitting infra-red would fog an infra-red film. Secondly, the normal photography: This requires that when the 'flash' from the camera gets you, something flashes back. Preferably two flash sources either side of the vehicle registration plate (to fog the film again). However, the cameras might not flash in daylight.
Then again, they also use video cameras. Have you noticed the rather large circular or square white painted blobs in the road? They are 1/10th mile apart (or 2/10ths on motorways). I'll let you guess why that is....
So to answer the question, yes, it is very possible that it is pointing at YOU!!
Firstly, they have to measure your speed. This bit can be done in two ways. One way, by using piezo-electric strips embedded in the road; two such strips at a known distance apart will detect your wheels over them. The time it takes between the two strips gives the speed. (Speed equals distance divided by time.) Another way is to use radar. By emitting suitably high-frequency radio waves, they can bounce these from the vehicle, and the rate-of-change of distance is detected by a frequency shift from the reflection. If this rate-of-change is higher than the rate-of-change for the speed limit, you're caught

Next, they have to photograph the vehicle. This bit sounds easy but is not so straight-forward. The photographs taken will be both normal and infra-red. (The infra-red will 'see' your registration mark when the vehicle is caked in dirt.) Also, to collect the proof, two photographs are taken in quick succession, so that the distance travelled can be seen. Obviously the "quick succession" is a known time: Again speed can be calculated. To determine the distance, white square marks are usually painted in the gutter of the road and again on the crown of the road. These are a known distance and the two photographs will show the distance travelled.
How do we avoid getting done????
Again, in order. If there are piezo-electric strips, there is nothing practicable that can be done

For the boffs amongst you, current technology uses X Band radar (which is really microwaves). The frequency is about 10 Gigahertz, which (take it from me) yields about a 30 hertz frequency shift for every one-mile-per-hour travelled. If you are travelling towards the source, the frequency is added (and goes up) and goes down if you are moving away by the same amount. 30mph gives a bit over 900 hertz shift. If another (similar) radar source were to mix its frequencies with the reflected ones from the camera, you would confuse the living daylights out of it. It might record your speed as something very erratic and probably impossible! It also shows that these cameras can photo objects coming towards them as well as going from them. It would strike me that either the camera has the facility to photograph the oncoming and departing vehicle, or the police can alter the angle of the camera and focus it on either side of the road


The photography bit would be interesting, too. For the infra-red part - simply drill some small holes in the vehicle registration plate to take infra-red emitting diodes. A number of them permanently emitting infra-red would fog an infra-red film. Secondly, the normal photography: This requires that when the 'flash' from the camera gets you, something flashes back. Preferably two flash sources either side of the vehicle registration plate (to fog the film again). However, the cameras might not flash in daylight.
Then again, they also use video cameras. Have you noticed the rather large circular or square white painted blobs in the road? They are 1/10th mile apart (or 2/10ths on motorways). I'll let you guess why that is....

So to answer the question, yes, it is very possible that it is pointing at YOU!!
Last edited by RQ on Fri Sep 03, 2004 3:49 pm, edited 1 time in total.
RQ.
The Stig of 2 wheels as well as 4 !
The Stig of 2 wheels as well as 4 !
must admit i thought the lines on both sides of the road were so when they are looking at the pictures they can hold a rule accross the coresponding lines at either side and judge how far away from the camera you are by getting a square line accross the back of your vehical.
thus determining your speed as a double check to the camera's printed data.
thus determining your speed as a double check to the camera's printed data.
cheerz
kev
kev
Lines on both sides........
Been away, good to see the site is still going strong. Anyway, the lines on both sides when only a camera on one......either because a gatso on the other side is planned in the future OR, just like all those signs indicating radar when it does not exist, just to worry the motorist into slowing down, simple as that.
As for radar detectors......waste of money. Pick up on all sorts not just radar but mainly because the Falcon hand held radar only emits a signal when pointed at a vehicle and the trigger is depressed. It can lock a speed in less than 2 seconds. Now even if your detector goes off in 1 second are you really that good to slow down in the other second.....naaaa.
As for radar detectors......waste of money. Pick up on all sorts not just radar but mainly because the Falcon hand held radar only emits a signal when pointed at a vehicle and the trigger is depressed. It can lock a speed in less than 2 seconds. Now even if your detector goes off in 1 second are you really that good to slow down in the other second.....naaaa.
Radar detectors
Yeah, these things work well, but it's all aimed at Gatso's and lets face it there are usually loads of signs, a big ruler on the road and, if you live nearby, local knowledge so it's still a waste of money.
I should think you could have an automatic revolving number plate made for the price of a radar detector.....job sorted.
I know someone who worked in a motor accessory shop who went to the trouble of making up a number plate that said 'UP YOURS', stuck it on his mini and went through a Gatso at great speed. You can only hope there was a camera in that one.
I should think you could have an automatic revolving number plate made for the price of a radar detector.....job sorted.
I know someone who worked in a motor accessory shop who went to the trouble of making up a number plate that said 'UP YOURS', stuck it on his mini and went through a Gatso at great speed. You can only hope there was a camera in that one.
Hi all about these Gatso's,. check out this link http://www.speed-detectors.co.uk/catalo ... p/cPath/48 it may enlighten you a little don't bother with cheap detectors you either get loads of false alarms or the range on gatso's is p--s poor hope this helps Floydy