FREE Hidden Electricity!

Picture of FREE Hidden Electricity!
This Instructable will show you how to tap into a FREE source of electricity! All you need is a phone line! All phone lines have a constant flow of voltage, around 40-70 volts (up to 100 volts when it rings!), but you can't just plug stuff into it and expect it to work. You can really mess with your phone system by doing that. I discovered how to do it the right way!

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Step 1: What You Need...

Picture of What You Need...
1. Small project enclosure
2. (1) 240ohm resistor
3. (1) 510ohm resistor
4. (1) LM317L Regulator
5. (1) KBP210 Bridge Rectifier
6. (2) Phone line cables

Step 2: The Schematic...

Picture of The Schematic...
I connected the Positive end to one line of the female phone jack and the negative to the other. You could wire it directly to your light but I chose to do it this way so I could test other sources with just a phone jack interface cable. The Red and Green go to corresponding colors on the phone line that plugs into the wall.

Step 3: Final steps...

Picture of Final steps...
Mount the circuit in the project box and run your wires through two small drilled holes. Be sure to tie knots in the wires inside the box to prevent them from pulling out.

Step 4: Interface Cable...

Picture of Interface Cable...
I made an interface cable from an old wall adapter and phone line to connect the light to the box.

Step 5: Test it Out!

Picture of Test it Out!
After wiring the LED's in parallel, I plugged everything in and it worked great! It even powered off when the phone was picked up and flashed when it rang. While this won't power your new 60" HD Plasma TV, it will power small amperage electronics and could come in handy if the power goes out! Enjoy your FREE source of power.
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arc862 years ago
If you do this don't be surprised if the phone company finds out about it. But I want to offer a couple corrections.

First, don't use the KBP210 Bridge Rectifier. That's used to convert AC to DC but the voltage on the phone line is already DC so all it does is waste 1.4V of your power source (when current has to flow through diodes it burns up extra power). You can tell he has his multimeter set on DC voltage in the video, this verifies that's what's coming out of his wall jack. I guess it would save you if you accidentally connected the green and red wires backwards but just don't do that.

Second, if you already have DC, figure out what voltage you need for your device and use the LM317L or another adjustable regulator. He has the resistor network connected incorrectly so refer to the datasheet from Texas Instruments. What you need to do is hook up the resistors so when you get your desired voltage on the Output pin, the Adj pin sees 1.25V. The way he shows it hooked up it looks like the circuit will just output 1.25V (the Adj pin draws so little current it's at effectively the same voltage as the output it's hooked to through a resistor). You need one resistor going from the output to the Adj pin, and one going from the Adj pin to your ground.

Anyways, check your output with your multimeter before you hook it up to your valuable electronics.
usbg3rd arc862 years ago
i found out that the phone line contains 50-60V dc and a 110Vrms sine superimposed on it so u will need a rectifier ic too .....

i wonder why he isn't using filter capacitor? ???

by the way nice hacking :)
iTixle usbg3rd1 year ago
It makes no sense to me that the voltage would be DC. You can't transmit DC over very long distances.
That's a very large misconception. In fact you'll find that for high power long distance transmissions DC is far more cost effective.

Actually, for anything over more than a few metres, DC power transmission has massive losses. High voltage + low current = much less resistance.

One if the main reasons cities went with AC was that DC system designs needed a power station almost every other block. Modern high-rise structures would need piwer stations part-way up the building.

usbg3rd iTixle1 year ago
chk out urself just need a voltmeter to do it the suprising thing is that when u try to extract power from it it goes to very low value
Zevion arc862 months ago

could you make an schematics on this description ?

dudes2 months ago

is it legal in the united states of america? specifically Ohio?

Kiteman dudes1 month ago

Try asking your phone company...

donclark2 months ago

Very curious! Is anyone selling these as a complete kit, or something similar? I would like to use an old phone jack to power 2 usb ports or more, led night light - or ac outlet and keep the phone jack too. Or could someone point me to someone that would create it for me (for money)?

BurgersBytes3 months ago

To anybody questioning the need for the bridge rectifier, it is required to rectify the 90 volts AC when the phone line is called. If you get voltage on an inactive phone line then it will probably just deliver DC, but ya never know. Imagine if everybody did this! Somebody has to pay for it!

promach10 months ago
If I do not have KBP210 at my local electronic stores, what other rectifier chips can I use in place of KBP210 ?
Nikola Tesla figured this out almost 100 years ago. Supposedly the generator he devised could be made by virtually anyone. But for some reason his discovery wasn't publicized. Until recently that is. It's quite an interesting read.

The rest of it is on
milkdud551 year ago
Why dont you find a neigbor a outside plug and combine
i guess you couldn't power much as the phone line will have a pretty low ampage.
JerryBYong1 year ago
Hi guys, I know this instructable is kinda old but I was wanting to make this into a USB charger for my Android phone and portable charger. I currently do not have a land line registered at my home so it won't ring. So can I hook up a car charger to it?
I worked for at&t. When youre disconnected from at&t, thats done via computer. that pair of wires is now up for grabs. So your pair of wires have a Pair number. it can be assigned to someone else getting services. If you have good decent quality wire (something not at all common in urban areas, to do poor quality upkeep) your pair will be used by some line tech for a trouble call of another customer needing a new pair of wire.
But if you disconnect, and no lineman takes that pair, you will still be commected at the crossbox (the big box in the area.) it has 48v coming off it. the only way THAT drops is if the Central office that the Box is running wire from, disconnects you from there. So YES that is free power. this is what I was thinking. Why cant I take the power from there, stick it into a dc to ac converter that is grid tie style, plug the AC cord from the converter into a wall socket, and Add clean power to the electrical grid...therefore get less off my electric bill?

Listen, you can get a Pay for all calls LAN line that is like 13 bucks a month. NO features. In fact, you can get a call that is only outbound. therefore no telecommunicators (at&t is KING of that mess. while working there, the COMPANY ISSUED PHONE...was always inundated with telecom calls from india talking about winning stuff!) But i feel, forget trying to run anything off it. use it as if it were a solar panel, and do what a solar panel would do.
What are the resistor specs? Are they 1/4 wat, 1/2 watt? +- .5 %, .o1%?

From the pictures you have posted they are 1/4 watt axial. But who knows?

You really should post this info as people going to buy these parts to build this will not know what values to get.
at that level 1/2 watt is plenty
and from what i can tell from the poor picture qual , they are 10% tolerance
smuhammad52 years ago
If we get 12volts DC by voltage divider.Can we provide that to a power inverter means UPS??????
plzzzzzzz answer me
Also, what is the voltage and amps acheived?
Maccer3 years ago
Is this legal?
Taddle Maccer2 years ago
Depends where you live
Depending on how much your phone draws, couldn't you technically power your phone just off of this?
Older phones did actually use the power from the phone line
Super_Nerd2 years ago
Technically, this isn't completely free, because phone service isn't free. However, there isn't any extra cost, so I would say...

Money saving hidden electricity
Sometimes, power can still come through even if you're not connected to the service, it depends on how the system in your area works.
My question is: Can you hook an iPad to this and have it charge?
Probably, find out how many amps your phone line is kicking out using a multimeter and multiply that by the volts. If your answer is over 10, yes.
ocelot16335 years ago
now this "conversion" is still DC power right? Would there be a way to convert this to AC power w/o using a "power inverter", even building one, for us creative techish people...I've done alot of research and such involving transformers 555chips mofest etc... was wondering if you had any input...
it is ac from the wall socket so you just take out the diode bridge rectifier.
So, the phone line power is AC, and not DC?
yes/ and a big tip plug your test meter into it and turn it to DC on the control dial , if their is no reading but a reading on ac then the line is ac, PS do not put fingers on wires it hurts!!
Hahaha, I know that one 2 well, I just hooked up a Wireless unit outside and made a makeshift outlet outside, and I went to unplug it to bring it inside to reconfigure and I grabbed the entire Outlet and I couldnt feel my arm for the next half hour... just glad it wasnt 220, buddy went to the hosp for that, but I know what your saying.... Test with DC with a Multimeter and if no power, then try AC.. but then how would one convert this 50 - 70 VAC line to 110, or down to 12VDC and use an Inverter and bump it back upto 110VAC?
This is an ancient thread, but why not simply make an auto transformer. It could be air core, ferrite core, over even regular transformer steel at 50 to 60 Hz, so it would not matter. The only thing I'd suggest is to use about 28 awg magnet wire to not make it looke like a dead short to the input and then add the necessary resister to the input to not cause phone troubles. Do a google search for autotransformer and you'll see how easy one would be t omake.
you couldent use an inverter because the amps would be too low but to get 12 volt at low ampage you can use a L7805cv voltage regulator, and sorry to hear about you and your freinds misfortune
touch 1 wire not grounded: nothing
                             grounded:slight twinge
touch both grounded or not grounded: not cool
nodoubtman2 years ago
thank you it works wonderfully... but i did a bridge diode with 4 1N4007 Instead :) i have built a beautiful lamp by the way :)

THank YOu again! :)
siddhesh512 years ago
can we connect the two wires coming from the telephone port directly to the load without using Rectifier ,Regulator and resistors for my lappy ?????????????? plzzzzzzzzzzz help !!!!!!!!!!!!! thnx fr the suggestions frndsssssss!!!!!!!!!!!!!!!!!!!!
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