A simple solution for powering up low-voltage DC devices in public spaces. When you plug this in, one of the plugs is powering an outlet on a decoy junction box and the other plug is providing a continual power source to a low-voltage DC device. This is something that I have been fiddling with for ages and it is not quite done, but I put it online due to the urging of some friends who find the information useful. Maybe you can figure out the final step (I will explain later).

PLEASE NOTE: This project uses high-voltages which are inherently dangerous. Additionally, I am not an electrician and can not verify if this project poses a fire-hazard. Lastly, I am pretty sure that the use of this project on other people's property would be illegal.

***Construct and use at your own risk.***

Step 1: Go Get Stuff.

You're going to need things to do this:

1. A standard wall socket
2. An outdoor socket cover
3. A cell phone charger (preferably 5V 500ma)
4. Two grounded wall plugs (like the one below)
5. A 1" x 2.5" piece of lucite that is of 1/8" thickness
6. Electrical tape
7. Thick stranded wire (the one below is from a strand of Christmas lights)
8. A plastic 1/8" pull-tie (not shown)

to be explained in final step:

9. Casing and paint (not shown)
10. Epoxy (not shown)


1. A Phillips-head screwdriver
2. A pair of pliers
3. A Dremel (or laser cutter)
4. A utility knife
5. Wire strippers
6. Soldering iron
Have you tried an old-work exterior box such as the one found <a href="http://tinyurl.com/oldworkbox1">here (Lowe's)</a>?
I've had the same thought, looking at the boxes installed near the bases of downtown sidewalk trees, where they plug in the strings of lights for the holidays. Just on a lark one day, I brought a 3-light tester with me and plugged it in. No love, the boxes are turned off when they're not in use. Now I wonder where the switch/breaker is! Wifi repeaters and network cameras are the obvious choices, and there are some damn small WDS-capable APs out there. Sensor networks could be fun, and any cellphone programmed to auto-answer in speakerphone mode could be used as a simple remote audio bugging device. I'm not sure why you'd want to watch or bug the sidewalk, however. Repeating free wifi into a poor-coverage area would be hilarious. It's a shame the standard is so ill-suited to that.
Most of those outlet boxes you see near trees, walk ways and in light poles are controlled by either a photocell or a timer. That way they are not wasting power during the day. I'm a electrician by trade and a few things. #1 You will not be able use only part of a GFCI outlet due to it having an internal circuit board and solenoid, coil, and contacts that make it work. #2 if you simply half a regular duplex outlet you have internals that are very dangerous and will have to be insulated. #3 In the USA a standard out let is 125VAC at 60HZ, it's very noisy so attempting to put any receiver or transmitting device in the same box will have a issue. #4 Tampering with any outlet in a public place (park, ect) will most likely end you up in jail due to vandalism and theft of city services. <br> <br>The concept is a kool one but not a wise one. As far as wifi repeaters you would spend major bucks and have to but then all over just to cover a small area. Not to mention that if your ISP catches you giving out free wifi with intent it's very bad news (cancel service, and might end you up in court). <br> <br>The one statement about the romex wire being able to stab into the back of the receptacle is correct but it only goes up to 14awg solid wire. Most Boxes are of the 18cubic in type and don't have a lot of room in them you would have to have at least a 22-24 cubic inch box. They do make extension rings for the outside ones and it comes with longer screws. From experience no matter how well you seal the cover it will get moisture inside and if your making one that have a PC board in it you;ll have to epoxy dip that board to keep it dry. <br> <br>To be perfectly honest with all you would have to do to adapt a outlet box and such to achieve what you want isn't really worth it. <br> <br>Easier just to get a pinhole wireless cam and mount it inside something thats already there (clock, smoke detector, light fixture, ect) <br>
A actuall use for a group of wifi repeaters could be saving money on phone service. This way, you can use a skype phone while you are in certain places in the city You could probably get a group of people together to help out the cause.
With a little effort you can do this "above board" involving local business, parks and rec. Organizations love opportunities to participate in public projects that cost little or no money.
I don't really see a point in this as it is, because they will still see your cords coming out of it. But, if you were to leave the device there and want to conceal an outside connection for your use, I would think about removing the old plug altogether and hardwiring it into their junction box and using their face plate. A small spacer ring could be made to enlarge the depth of the box for your needs, say 1/2 to 1 inch ( longer screws would be needed also). Diable one plugs and take the back half off for more room also, or use a different face plate and take it out altogether. If it is for changeing a phone without a cord like one guy was having trouble with I would just place the phone charger in a thin box that could hold a spare battery for my phone. Make the top of the thin box look like a blank plate so people will think the plug has been removed or blanked off. Remember also that most outdoor plugs (at least here in Canada) have to be Gound Fault Safety plugs and it should look like one of them.
I think wireless would be the best use.&nbsp; If you could fit something inside that ran on DC that transmitted wirelessly, even over radio, then it could be useful.&nbsp; A couple thoughts are: spy cam, network repeater/range extender, remote switch(that cuts power to the remaining outlet) to piss off the target, network traffic spammer(if you can connect it to their wireless you could DOS them).&nbsp; I am not the type of person who would use this sort of thing and it is definitely not legal in most cases but I applaud randofo for the originality.
lol, "bling"
nice fence Oakland? New York? San Francisco?
Bushwik section of Brooklyn....
Perhaps a plastic retrofit outlet/switch box from a building centre (e.g. Home Depot, <a rel="nofollow" href="http://www.acehardwareoutlet.com/ProductDetails.aspx?SKU=30737">Example</a>). An exterior box model may be easier to weatherproof.<br/><br/>I'd also suggest paying attention to weatherproofing the box if it is intended for outdoor use. Water and electricity don't mix.<br/><br/>The wiring of the plug to sockets should be double checked with a 3-prong AC tester (e.g. <a rel="nofollow" href="http://www.tripplite.com/products/static/ct120.cfm">U.S. model</a> or <a rel="nofollow" href="http://www.maplin.co.uk/Module.aspx?ModuleNo=9800&doy=7m12&C=SO&U=strat15">U.K. style</a>) - they are infinitely handy to have anyhow.<br/><br/>Heat-shrink tubing is more durable than electrical tape for insulating the wiring joints. And I find it easier to make a neat and tidy seal. <br/><br/>
Using something like this <a rel="nofollow" href="http://www.mouser.com/catalog/626/1468.pdf">http://www.mouser.com/catalog/626/1468.pdf</a> <br/><br/>You might be able to make something like this picture. (Sorry for the lack of detailed schematics.)<br/><br/>Now that I think about it, it might be easier to just put the thumbscrews in the top/bottom so as to allow more room for the circut board. It might be better to use 1/4 turn screws similar to those that they use on race car bodys, to make it less tempting to exploring little boys....then again, I dont know where you would get something like that.<br/>
Those can be had at a race car shop, or even a local hardware store...they have ALL KINDS of great fasteners. go visit one and your wheels will definitely begin to turn......Also, those screws don't need to be used. The outlets have very small holes in the back of them to accommodate standard Romex solid copper wiring. Simply strip the wire, and plug it in.
oh boy...I just realized that the picture shows the screws penetrating the inner outlet.
I don't understand why this is needed. I always plug stuff in wherever I am at and have never had anyone ask me to not do it. When it's been in a store, coffee shop whatever I ask and have never been turned down. I've done this in Seattle, NYNY, Detroit, Denver, Boise, Salt Lake etc. Why do you need to hide the fact your charging a phone or laptop etc???
It could be used for powering homemade wireless electronic devices, discreetly, for long periods of time.
I still don't see the need. Just plug it in an outlet near the floor or ground in a open public area and most likely no one would even notice it for up to a year. Why even try to conceal it? Leaving things in the open is the easiest way to have it go unnoticed. Even employees will often assume management put it in, etc. I've plugged in a charger with my camcorder battery in it to charge in a food court before and forgot it latter. Didn't come back for over a week to get it and no one touched it. It was right at floor level and you could even see streak marks where someone had moped around it! If it has no labels, is just a little piece of black electronics they have no idea what it is and they often make stupid assumptions. So just be sure and peal off any stickers etc. In high crime areas it's generaly stuff that your trying to keep an eye on that gets stolen, not stuff that you just place in a out of the way spot and ignore...
You clearly have never lived in New York City.
Seems like with all of the effort and expense of doing this ... you could just get some solar cells or some other power generation (small wind generator??) and a couple of batteries and have the same thing with out messing with someone elses outlets. Especially since we are talking about only trying to power a low voltage DC device.
The problem I was having with that approach was that in New York City (where I came up with this) you never quite got enough sunlight at street level for it to be reliable and windpower devices were too visible for what I was doing.
Is NY so very bad that being seen winding a small handle will get you mugged?!?<br/><br/>You could perhaps go for one of the rotating magnetic charger designs that capture your movement and turn it into electric for your stuff. Or this - <a rel="nofollow" href="https://www.instructables.com/id/EE9ZG6JF1OABQAQ/">Stealth charger</a><br/>
It's not the criminal element you have to worry about. It's the "see something say something policy." People can sometimes get awfully worked up about nothing these days. Also, New York is rather horrible in regards to objects being left in the public space. Anything not chained down and left unattended longer than 30 seconds will walk away. I once saw someone try to runaway with a full-body mirror left in the doorway of a glass shop in broad daylight.
Hopefully they were dumb enough to run into something like a lamppost because they could only see behind them. :-)
Great Instructable. I love the brainstorming that has followed!
Why not just try to get the subways to offer this kind of phone-charging; they could up the fare by a nickel, to pay for it & it would benefit many.
well this has a great use in the uk trains have cleaning sockets at various point including where a bunch of mates may site just beside the bike area and toilet so its handy there as the conductor made me get off the train when he saw me charging my phone outta one of these so it has its merits
Theft of services!
i still dont get what you did here
he made a fake 'cover' for a power receptacle, which you plug in somewhere. It still functions for regular plug-in stuff, but housed within it is a cel-phone charger, which you could use to power things...but covertly.
i still dont get it
Bling indeed! Very Fly Project.
this seems like an awfully long way to go to bleed off alittle power and leave an outlet sticking 1-2 inches off a surface. even if i could think of a real-world use for this on a lamppost or something, can't you just open the existing junctionbox and place your bleed in there?
i have no idea what this does
I am going to ask the same question. WHAT DOES THIS DO? I understand it's for low dc stuff but what is it's function, what would you usethis on? What type of circuit would you throw in here.
I found something to use it with!!!<br/><br/><a rel="nofollow" href="https://www.instructables.com/id/E8J1TA6ZVQEQOEX573/">unwrapped: Kommunikations-Gully</a><br/>
This device lets you use a low-voltage DC device without blocking any outlets. you just plug it into a recessed duplex plug, with your dc device hidden inside, and it will bring the outlet flush with the wall. It will look normal while the hidden DC device does something. At least I think that's what it does. I haven't read the instructions yet.
First off, yes this is a fire hazard (by electric code) at its current setup. Not being a qualified electrician, but knowing and playing with electricity there are a few things that should be changed (not to make it up to code, but safer at least). The wire should be at least 14 AWG if not 12 to prevent overheating, that will be up to code then. The best way I can think of to explain the wiring is, in north america, all outlets, plug ends, ect. should be color coded by screw terminal. White to silver, Black to brass and always green to green. Allways connect green first and black last, even if u know that the circuit is not live. The only other obvious fire hazard would be the transformer, they are cased with x amount of room in order to allow cooling if that is reduced, then at the very least you fry one transformer, at the worst you have a fire, so beware of that hazard. Apart from that very nice project, I have hacked togeather many an electric device in my day that looked and was much less safe than this good start.
You can probably stop by the dumpster of a local subdivision going up and pick up some romex to wire it too. But I can never remember if this is legal.
if it's in a publicly accessible place, in the trash, and not locked, i believe it's legal.
I think that 12 guage awg is better.. the smaller the number the thicker the wire and less resistance... see: <a rel="nofollow" href="http://www.interfacebus.com/Copper_Wire_AWG_SIze.html">http://www.interfacebus.com/Copper_Wire_AWG_SIze.html</a><br/>
Hmm "This is coming from someone who has been electrocuted many, many times." Doesent electrocuted mean killed with electricity?
electrocute |iˈlektrəˌkyoōt| verb [ trans. ] (often be electrocuted) injure or kill someone by electric shock : a man was electrocuted when he switched on the Christmas tree lights. -Oxford American Dictionary No, no it does not. It means to be INJURED or killed by electricity. It would be foolish to tell you that I was killed by electricity many, many times. However, I can appreciate your concern for my well-being. Thank you.
pretty sure cpf is right. electro- from &quot;electricity&quot;, -cute from &quot;execute&quot; - a portmanteau - <a rel="nofollow" href="http://dictionary.reference.com/search?q=electrocute&amp;db=*">http://dictionary.reference.com/search?q=electrocute&amp;db=*</a> . electric shock would be the right term. perhaps the oxford american is caving in to public misuse?<br/><br/>great tut, I can imagine the CIA or some such group picking up on this and starting to use it. you could have something it in using bluetooth, picking up (and/or sending) messages from (to) people's phones, and stuff like that. really cool<br/>
Bluesnarfing or whatever it's called...
Hmmm.... If you made a bunch of these, and used a wifi repeater in each, then you could help out with the city's WiFi network. Or sign up to Fon as a Bill ]:)
Cool, wifi repeaters and radio transmitters are the 2 things that come to mind
electrocuted and back from the dead!
It could power spycams, electro-paint, (as the author mentioned), mics, a small cell phone for snooping, hundreds of things. You could add a small 1/8 inch stero plug to the case so you could walk up to it, plug in a stereo plug you modde to a device and get a quick charge to some sort of device. You could embed a tiny rfmodulator and some sort of annoying or spam like sound on a cip and whenever somebody drives by they hear your sound on their FM radio for as long as they are close. You could make LASER BEAMS THAT CUT PEOPLE ANKLES OFF. Cool start.
randofo, what type of low power dc device were you thinking of using when you made this, i like idea because once you make it, it can be installed in seconds. and with the casing, if you you added a bead of caulk on the bottom (where it would butt up to the wall) it would possibly provide a nice inconspicious seal. also, could you include a picture of it in use.... if even only at your house? thanks

About This Instructable




Bio: My name is Randy and I founded the Instructables Design Studio. I'm also the author of the books 'Simple Bots,' and '62 Projects to ... More »
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