Just got a spam e-mail from some group in Miami selling a remote traffic signal changing device for $79.95. The claim it works from 100’ and will change the signal cycle. Very clear about all sales final and not resopnsible, sign disclaimer, blah blah… not that I’m gonna buy one but any comments or knowledge?
from http://howstuffworks.com/
How does a traffic signal know that a car is waiting?
Describes how traffic signals generally work–doesn’t sound like a remote control would work on it.
“Why, sometimes I’ve believed as many as six impossible things before breakfast!” - the White Queen
Emergency vehicles in some places use what is called Opticom, a device made by the friendly people at 3M*. It consists of a strobe light flashing at a certain frequency mounted on the vehicle, and a sensor on the traffic light. The sensor sees the strobe light, and changes the light to green for that direction.
More about it here: http://www.3m.com/market/trans/its/prod_priority.html
Perhaps they’re trying to sell a counterfeit transmitter unit? Of course, it would only work if your locale used Opticom.
*This is in no way to be considered an endorsement or advertisement for the 3M corporation
Jeremy…
Nobody ever calls me after they’ve done something smart.
Some traffic lights have a strobe fixed to the top of the light assembly. These lights are equipped with a radio-controlled device that can be activated by emergency vehicles.
When activated, the lights turn red in all directions - at least the ones around here that I have been able to observe in operation do. The emergency vehicles can see that they are operating by looking for the flashing strobe light.
If the device you have seen actually works, it’s probably activating lights of this type.
Needless to say, unauthorized use of an activation device would violate several laws.
I actually own a device that does this. Around most of California, and many other states, ambulances and firetrucks have a strobe light that flashes which triggers a sensor on top of traffic lights that turns the signal green in their direction, and red in every other, resetting the signals. Basically, they are selling you a strobe light flashlight. I bought it out of the back of Popular Science about five years ago for slightly cheaper than what you were quoted (I think I paid $49.95)
I personally have found it’s really not worth it. It only works well at night, and even then, the weak power of the flashlight means that unless you are the first or second car back at the light, you will be too far away to trigger it. Plus you tend to freak out the any drivers in front of you, who can clearly see you using it. And you’re talking a guaranteed bust if one of these people happens to be an off-duty cop. At first, I went nuts with the thing and kept it in my car all time using it every time I could, like an idiot. But there were all kinds of times when the light would turn green and the person in front of me would stop because they didn’t understand why I was shooting a strobe light through their back window and that I must be a cop/ emergency vehicle, etc. Plus, most times when I was stuck at a light for what seemed like 100 years, I was always like 10 cars back where I was out of range. Now it sits in my closet and I only use it when someone wants to see it.
Hell you could probably convince me to just sell you thing if you want one that badly…
My husband and his friend once drove around Oahu turning all the traffic lights green with a TIMING LIGHT. They had it plugged into the lighter on the dash, and simply pointed it at the ‘strobe thingie’ at the top of the lights and pulled the trigger.
I wonder if there’s a law?
It turns the light green? That’s surprising. The systems I’ve seen (in Ohio) foil cheaters very simply - they turn all the lights red when an emergency vehicle approaches, so only the emergency vehicle can legally proceed through the intersection. (They also illuminate a small white light so the driver of the emergency vehicle knows the system is working.) So a cheater could hold people up in traffic for a while, but there’s no real incentive to do it.
The times I’ve seen it work (in southern IL and in SC), it turns your light green and all the others red. You could get it to work by flashing your brights a few times.
I’ve also heard that the sensors are sensitive to light beyond the visual spectrum, so if you got a UV strobe, no one would see a flash coming from your car before the light turned green.
A nickle saved…is a stockpile of nickle.
And risk death by gang initiation? No thank you!
Tony Soprano: We’re the only country in the world where the pursuit of happiness is guaranteed in writing… Where’s my happiness then?
Dr. Melfi: It’s the pursuit that’s guaranteed.
Tony Soprano Yeah, always a fucking loophole.
Hey, it beats getting hit by a spunkball while you wait for the light to change.
I don’t know what system they use around here, but in Stanley, KS (where I worked over the last two summers), if I flashed my brights fast enough, the light would change. I stopped doing so when a friend got pulled over for it.
–Tim
You can’t accidently create a handicapped baby whilst smoking pot. - Coldfire
We discussed this previously at Traffic Lights.
You cannot flick your brights fast enough to trigger the sensor. The strobes are cycling much faster than you realize or can manually reproduce. Thinking you have managed the feat falls into the category of thinking you make lights go out because they have gone out when you passed; it’s simply luck.
I note that the Opticon™ system from 3M™ works in the infrared frequencies, so headlights wouldn’t affect it.
As for what the sensors do, I would expect based on personal experience most of them result in the light changing green for the direction in which the emergency vehicles are travelling. This facilitates clearing the traffic stopped in front of them, allowing them to procede through the intersection unimpeded. The Opticon™ system states that is how it works. Perhaps someone can post some data on other systems being used that describes what the options are.