Hi, > > Some time ago getting a idea to make speedtrap > > warning device with help using normal GPS > > receivers. > > Myself totaly no software coder or what so ever and > > only have this idea in my mind. This wouldn't be because such a device is now commercially (although under investigation and possibly soon outlawed together with speed radar jammers) available in the Netherlands? :-) It's not too complicated an idea, you have fixed positions for all known camera's as well as the direction they look in, and if the current position is on a collision course (about) with a camera it will sound a warning. In the commercial version they have added speed-limits for all roads as well, so the device knows how fast you are allowed to go there. It of course knows your car's speed via GPS. Actually since you can approach the camera from a corner (where collision detection would be too late) they probably took the camera, then added a waypoint 500mtrs before and after the camera, once you cross this line (run over the waypoint so to speak) you are in a camera hot-spot. Then again maybe they just use a 250mtr radius around the camera (math, yay :-) Dennis -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.