I think it works between toll sections. You pick up a ticket at A, drive like a maniac to toll section B, local plod calculates your average speed and nicks you.
I would have thought that as well, however I've seen the signs (and my gps - WAZE) tells me I'm entering / leaving the average area and I'm nowhere near a toll booth.
Nope. This is a myth that's been around for twenty years or more, and has been busted several times over (for France, at least). Probably based on the gendarmes using the toll station as a convenient way of stopping cars that had been zapped by a hand-held radar some way back down the road.
they are using these in Holland too but I'm not sure if they measure only the average speed or also the actual speed at those points (3 chances to win a speed ticket).
Not to give advice to others but going 150 km/h between Milano and Venice even with 'Safety Tutor On' signs had no unpleasant consequences for the past 7 years (traveling some 3-4 times a year). A few times I passed a police car (following the locals who did the same).
Between Venice and Trieste there are some weird cameras on the side that point to the road at a 90-degree angle and I never figured out what those do (only seen one flash once). They have a sign on top of them - a police hat (like that of a London bobby) - so can be seen from 100-150 meters away.
I believe in Italy it actually is about safety - if the road conditions permit traveling above the speed limit without endangering anyone then you won't be pulled over.
We do Lugano-Trieste several times a year as wife has an inherited house there (her great grand mother left when it was still part of Austria, but her grandmother inherited it during WW2).
Anyway, I think that those things are fake (I presume that you mean the blue boxes?)
Average speed systems have been around for twenty years or more. They even have an acronym, SPECS . As already stated, they use cameras with number plate recognition to time your duration between entering and leaving an area.
The question often asked by cash-strapped local authorities is: can they be made so cheap that the entire road system can be covered? Well, watch this space...
Yes, the blue boxes with the 'bobby' sign on top - I did see one flash a year or two ago (some other vehicle) so didn't look like a fake but I still can't figure out what exactly it can catch with such a weird angle.
In the Netherlands these do not check for the speed at the moment of passing a camera and only check for the average speed over the whole traject. The camera takes an image which gets send to the central unit, this unit calculates the speed using the time and distance in between the cameras if the car passes another camera. (and mind that some of these controls do exist out of a row of camera's and not only two.)
Not really sure if they work, but in 4-years with regular crossing into Italy I've done a steady 140/150 following what seemed to be the traffic speed and haven't faced any consequence...to be honest you never want to go that fast given the hilarious lack of lane control from other drives.
Seems more like a polite suggestion more than anything else.
That's my experience in Italy, too, and sometimes at considerably more than 150.
Just a reminder to those travelling in France, the national speed limit was reduced last month from 90 to 80 km/h. That means that if you're not on an autoroute or some other road with a posted speed limit, and you're out of town limits, the speed limit is now 80 km/h.
Not all speed limit signs have been changed yet but I wouldn't gamble on the gendarmes or the courts being sympathetic, especially since almost all speed radars have warning signs in advance!
we've just got back from Italy, my tomtom has itallian speed camera locations built in, and I don't think we saw any cameras that hadn't either been totally destroyed or painted over, seems the locals don't like speed cameras lol