At 11:33 AM 5/5/00 -0400, Mike Lorrey wrote:
> > Three intersections locally now have what appears to be cameras mounted
> > above each center lane signal. There has been no public announcement as to
> > these being for surveillance, and from the angle they are mounted at, it
> > looks like they would have a hard time capturing driver's images and
> > license plates. Perhaps an image processing traffic light controller?
>Nope. Its a light pulse sensor unit that allows oncoming police, fire engines,
>and ambulances with their lights going to cause the light to turn green.
>a fun thing to do, especially at night: Learn to get a sense of the strobe
>of the emergency lights of these vehicles, then at night flash your high beams
>on and off several times at that rate (hopefully when nobody is coming in the
>opposite direction) as you approach the intersection. I do this and its pretty
>good at turning the lights green for me at intersections that have this
>capability. This is a good way to go through lonely intersections without
>actually breaking the law... ;)
No, these gadgets are not Opticon sensors. Those are up there, too. What I
see is a hooded, lensed box exactly like a CCTV camera, aimed down at
approximately 45 degrees TOWARD traffic. It would have a nice field of view
of the cars stopped waiting for the light. There's one camera for each
direction at the intersection - four in all.
The Opticon sensors are (here) small black cylinders with a tube jutting
out of either side, pointing in both directions of the road it services.
There is also a white floodlight that comes on when the Opticon is
triggered. They are nicely sensitive to IR, so a suitable pulsed IR source
would trigger them stealthily.
>If you are really smart, buy yourself a hand strobe with a variable
>keep it set to a frequency similar to emergency vehicles....as long as it
>doesn't look like a siren, you aren't impersonating an official vehicle...
My partner was a volunteer fireman, as well as being an anarchist. He made
such a strobe - built into a floating flashlight case, powered by 4 D
cells, range about 1000 feet. We've been too chicken to take it in a moving
vehicle, at least until we get the IR filter nailed down.
This archive was generated by hypermail 2b29 : Thu Jul 27 2000 - 14:10:32 MDT