# What is this gray, X-shaped, box thingy hanging from streetlamps? **URL:** \ **Category:** Factual Questions\ **Created:** [August 27, 2011, 7:13pm UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304 "2011-08-27T19:13:12Z")\ **Posts on this page:** 19\ **Page:** 1
**Author:** ![Hermitian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hermitian/32/470_2.png) [@Hermitian](https://boards.straightdope.com/u/Hermitian)\ **Post date:** [August 27, 2011, 7:13pm UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/1 "2011-08-27T19:13:12Z")
What is this gray, X-shaped, box thingy hanging from streetlamps? There are several in the area, like every other streetlamp. Here are some google streetviews of them. [Overall picture of streetlamp.](http://img402.imageshack.us/img402/418/unledykm.jpg) [Closeup of X-box.](http://img716.imageshack.us/img716/6366/unled2vy.jpg) ---
**Author:** ![voltaire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/voltaire/32/313_2.png) [@voltaire](https://boards.straightdope.com/u/voltaire)\ **Post date:** [August 27, 2011, 7:15pm UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/2 "2011-08-27T19:15:15Z")
Looks like a heat-sink? ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [August 27, 2011, 8:11pm UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/3 "2011-08-27T20:11:19Z")
I’m thinking [wireless street light controllers](http://www.google.com/search?hl=en&source=hp&biw=&bih=&q=wireless+street+lights&btnG=Google+Search). Examples [here](http://www.streetlightiq.com/Products/Overview/NetworkedLampControl/tabid/174/Default.aspx) and [here](http://www.greenbang.com/wireless-tech-lets-cities-manage-street-lighting-from-pcs_10606.html), although they don’t look like yours exactly. ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [August 27, 2011, 8:16pm UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/4 "2011-08-27T20:16:56Z")
nm ---
**Author:** ![Hermitian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hermitian/32/470_2.png) [@Hermitian](https://boards.straightdope.com/u/Hermitian)\ **Post date:** [August 28, 2011, 12:00am UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/5 "2011-08-28T00:00:55Z")
> [@ZenBeam](#): > > I’m thinking [wireless street light controllers](http://www.google.com/search?hl=en&source=hp&biw=&bih=&q=wireless+street+lights&btnG=Google+Search). Examples [here](http://www.streetlightiq.com/Products/Overview/NetworkedLampControl/tabid/174/Default.aspx) and [here](http://www.greenbang.com/wireless-tech-lets-cities-manage-street-lighting-from-pcs_10606.html), although they don’t look like yours exactly. That is an interesting theory. Would it make sense to not have it on all of them? ---
**Author:** ![JBDivmstr](https://avatars.discourse-cdn.com/v4/letter/j/b4bc9f/32.png) [@JBDivmstr](https://boards.straightdope.com/u/JBDivmstr)\ **Post date:** [August 28, 2011, 12:06am UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/6 "2011-08-28T00:06:29Z")
I’m thinking a transformer. Most (all that I’ve ever encountered) streetlights are controlled by a photocell. It looks more like a transformer that is used to retrofit streetlights with a different type bulb. They are only installed as the current type of bulbs burn out and are then replaced and retrofitted for a newer, more energy efficient type. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [August 28, 2011, 1:13am UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/7 "2011-08-28T01:13:34Z")
I doubt it’s any of the above. It’s more likely to be wireless infrastructure for Public WiFi, or perhaps a macrocell. Can you use a pair of binoculars and see if there is any identification on it? ---
**Author:** ![Hermitian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hermitian/32/470_2.png) [@Hermitian](https://boards.straightdope.com/u/Hermitian)\ **Post date:** [August 28, 2011, 2:21am UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/8 "2011-08-28T02:21:33Z")
> [@beowulff](#): > > I doubt it’s any of the above. > It’s more likely to be wireless infrastructure for Public WiFi, or perhaps a macrocell. Well, if it’s a public wifi, it’s a secret one. I’ve never heard of it and nothing notable shows up on my laptop where I live (nearby). > [@beowulff](#): > > Can you use a pair of binoculars and see if there is any identification on it? Sadly, I do not own a pair. ---
**Author:** ![NinetyWt](https://avatars.discourse-cdn.com/v4/letter/n/cc9497/32.png) [@NinetyWt](https://boards.straightdope.com/u/NinetyWt)\ **Post date:** [August 28, 2011, 3:08am UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/9 "2011-08-28T03:08:45Z")
I agree with ZenBeam, either a traffic flow sensor or a streetlamp sensor. There’s another one shown on this [site](http://www.citysense.net/) (scroll down). ---
**Author:** ![jnglmassiv](https://avatars.discourse-cdn.com/v4/letter/j/f07891/32.png) [@jnglmassiv](https://boards.straightdope.com/u/jnglmassiv)\ **Post date:** [August 28, 2011, 3:30am UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/10 "2011-08-28T03:30:40Z")
WAG: Acoustic gunshot triangulation locators? > **[Gunfire locator](https://en.wikipedia.org/wiki/Gunfire_locator)** > > A gunfire locator or gunshot detection system is a system that detects and conveys the location of gunfire or other weapon fire using acoustic, vibration, optical, or potentially other types of sensors, as well as a combination of such sensors. These systems are used by law enforcement, security, military, government offices, schools and businesses to identify the source and, in some cases, the direction of gunfire and/or the type of weapon fired. Most systems possess three main components: > In g... ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [August 28, 2011, 3:31am UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/11 "2011-08-28T03:31:48Z")
What city are you in, **Hermitian**? Might be able to Google what it is. ---
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [August 28, 2011, 5:05am UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/12 "2011-08-28T05:05:03Z")
Photocell relays are vastly smaller than that unit and are typically integrated into the light head surrounding the bulb. Re a transformer a retrofitted lamp like LEDs would be using a completely differently shaped lamp head[like this](http://www.youtube.com/watch?v=lqIoX1ydoVs). It’s likely some sort of communication device. The wire leading from it is tapping into the lamp’s power. ---
**Author:** ![Bosda\_Di\_Chi\_of\_Tricor](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bosda_di_chi_of_tricor/32/16845_2.png) [@Bosda\_Di\_Chi\_of\_Tricor](https://boards.straightdope.com/u/Bosda_Di_Chi_of_Tricor)\ **Post date:** [August 28, 2011, 10:53am UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/13 "2011-08-28T10:53:16Z")
Do your local cops have a digital commo system? Relay unit? ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [August 28, 2011, 1:11pm UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/14 "2011-08-28T13:11:05Z")
Sort of looks like a node for a wireless mesh network. ---
**Author:** ![JBDivmstr](https://avatars.discourse-cdn.com/v4/letter/j/b4bc9f/32.png) [@JBDivmstr](https://boards.straightdope.com/u/JBDivmstr)\ **Post date:** [August 28, 2011, 3:35pm UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/15 "2011-08-28T15:35:23Z")
> [@Hermitian](#): > > Well, if it’s a public wifi, it’s a secret one. I’ve never heard of it and nothing notable shows up on my laptop where I live (nearby). > > Sadly, I do not own a pair. Maybe you could try calling your local public works dept. Here in Houston, there is a kind of catch-all number. (311) You call that # and they can either transfer the call or provide the correct # for which ever dept. you’re trying to reach. The wi-fi thing didn’t occur to me. (Good guess, beowulff.) Maybe that’s exactly what it is, and the reason you can’t pick it up is because the powers-that-be just haven’t turned the system on yet. ---
**Author:** ![Hermitian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hermitian/32/470_2.png) [@Hermitian](https://boards.straightdope.com/u/Hermitian)\ **Post date:** [August 28, 2011, 4:23pm UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/16 "2011-08-28T16:23:23Z")
> [@ZenBeam](#): > > What city are you in, **Hermitian**? Might be able to Google what it is. Um, DC metro area, that is about as specific as I can get. I have tried some googling, but couldn’t get anything. ---
**Author:** ![Hermitian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hermitian/32/470_2.png) [@Hermitian](https://boards.straightdope.com/u/Hermitian)\ **Post date:** [August 28, 2011, 4:25pm UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/17 "2011-08-28T16:25:00Z")
> [@Bosda\_Di\_Chi\_of\_Tricor](#): > > Do your local cops have a digital commo system? > > Relay unit? I have no idea. ---
**Author:** ![Hermitian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hermitian/32/470_2.png) [@Hermitian](https://boards.straightdope.com/u/Hermitian)\ **Post date:** [August 28, 2011, 4:29pm UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/18 "2011-08-28T16:29:25Z")
I did have one idea. The streets that I observed these on are roads used by the Metro Bus system. I wonder if it is some kind of bus tracker system so they can see where they all are and coordinate their positions. However, I have looked at some other bus routs I can’t seem to find them. ---
**Author:** ![Tom\_Tildrum](https://avatars.discourse-cdn.com/v4/letter/t/e95f7d/32.png) [@Tom\_Tildrum](https://boards.straightdope.com/u/Tom_Tildrum)\ **Post date:** [August 28, 2011, 6:04pm UTC](https://boards.straightdope.com/t/what-is-this-gray-x-shaped-box-thingy-hanging-from-streetlamps/594304/19 "2011-08-28T18:04:04Z")
As far as I can tell, [NextBus](http://www.nextbus.com/corporate/works/index.htm) just uses GPS units on the buses.