Easy Wireless Electricity

Please vote for this project if you found it educational, helpful, interesting, or just plain fun! Any comments or questions are welcome down below and if you find a spot where I've made a mistake feel free to let me know. I won't take offence.

Wireless electricity is something new and exciting. While its core principles are fairly easy to understand it can quickly become overwhelming for the average person. I faced a similar problem, I found the whole thing rather overwhelming to understand due to the fact that there were many different things that I felt I needed to understand to be able to make one. So when i found this schematic online I naturally had to build it. I think it's important to say that building one yourself does help you get a feel for just how exactly the technology works. Wireless electricity is basically electromagnetic induction. The transmitter coil emits a magnetic field when an alternating (Here's where I'm not 100% sure, please tell me if I've gone and messed something up.) current is applied to it. When the receiving coil's resonant frequency is the same as the transmitter coil's (Another not-sure moment here, if some one could link a good article or instructables post on resonance and how to measure/calculate it that'd be awesome!) then the oscillating field being produced by the transmitter coil induces an alternating current in the receiver coil. The alternating current that exists in the receiving coil is then turned into a d/c current through the use of a simple ac to dc rectifier made of a diode and two capacitors. Finally this dc current illuminates the LED.

Parts: (some are pictured some are not) (feel free to switch to the optimal stuff)

BD139 transistor

9 volt batter and battery clip

magnet wire/16 gauge wire

3D printed parts (only with 16 gauge wire)

10k resistor


Some connecting wire for use on the breadboard

Two (2) 470pF capacitors (all of the caps i used were only rated for 50v)

Two (2) 4.7nF capacitors

Two (2) 220nf capacitors

1N4148 Diode

LED (the lower the voltage the brighter it'll be)

Step 1: Circuit Assembly 1

Here's where it starts to get rather dull, just forewarning you it is very easy to loose track of where things go, if you follow these instructions and find that it wont work the most likely cause is that something in the breadboard stage didn't work, so make sure to look at the final stage to make sure that everything is 100% where it should be.

Place transistor on breadboard.

Additionally I'll be putting a link at the end of each one of these steps to the design page so that if what I've said isn't clear or is just plain wrong you can use it to troubleshoot and use as a secondary guide.

Step 2: Circuit Assembly 2

Place the resistor on the breadboard as shown.

Additional Help

Step 3: Circuit Assembly 3

Place the two 470pF capacitors onto the breadboard as shown.

Additional Help

Step 4: Circuit Assembly 4

Place a 4.7nF capacitor on the breadboard as shown

Additional Help

Step 5: Circuit Assembly 5

Place a 220nF capacitor on the breadboard as shown

Additional Help

Step 6: Circuit Assembly 6

Connect the positive power line as shown.

Additional Help

Step 7: Circuit Assembly 7

Attach the negative wire as shown.

Additional Help

Step 8: Circuit Assembly 8

Attach the output wires as shown. Note that the middle wire will go to the middle connector of the transmitter coil.

Additional Help

Step 9: Circuit Assembly 9

Attach the remaining 220nF capacitor to the LED.

Additional Help

Step 10: Circuit Assembly 10

Next attach the diode to the positive LED wire (you may want to check the schematic to make sure you're doing it correctly). after this you'll want to attach the remaining 4.7nF capacitor as shown in the second image.

Additional Help

Step 11: Coil Creation Version 1

You may want to use electrical tape or zip-ties to hold the magnet wire coils together, they have a tendency to spring apart if not held together.

Transmitter coil:

Wind magnet wire around a coffee cup 5 times, then cut the wire, make sure that there is plenty of wire on either end of the coil to connect to the breadboard. Then attach the wire at the end of the wire still on the spool, solder together, then wind again 5 more times in the same direction that you did the first 5 turns.

Receiver coil:

Wind magnet wire around coffee cup 5 times,make sure that there is plenty of wire on each end of coil to make connections to the LED setup.

Coil attachment: It may hep to look at the diagram for this

The middle connection of the transmitter coil needs to go to the middle wire the way we have set it up. the other two wires should be connected to the remaining two wires, you don't need to match specific wires, it doesn't matter.

The receiver coil is easy, just attach each end of the receiver coil to an end of the LED circuit.

Step 12: Testing

As you can see when the receiving coil is lowered into the field generated by the transmitter coil the electric current created lights the LED.

Step 13: Coil Creation Version 2 Files

It all starts with he design files, each of these must be printed twice. Once printed and assembled they will hold the 16 gauge wire used in this iteration in place.

Step 14: Coil Creation Version 2 Assembly

After printing the parts make sure all of the key features are in good condition, the holes may need drilled out a bit and the interlocking slot may need some material removed as well if the print didn't go perfectly. Next the printed coils must be assembled. This is a fairly easy task. Simply connect the two pieces using the built-in interlock slot in each piece, no adhesive required! Next you'll need to begin to thread the wire through the holes, the wire will hold the two pieces together and prevent them from coming apart no matter what. It is important to note that while the receiving coil is fairly straightforward to thread the transmitting coil does need to have the middle connecting point like in the previous coil.

Step 15: Wiring Version 2

Wiring version two coil is more or less exactly the same as the version 1 coil; the wires go in the exact same place. If you need to look back at the reference design here it is

Gadget Hacking and Accessories Contest

Participated in the
Gadget Hacking and Accessories Contest

Battery Powered Contest

Participated in the
Battery Powered Contest



    • Stone Concrete and Cement Contest

      Stone Concrete and Cement Contest
    • Planter Challenge

      Planter Challenge
    • Sensors Contest

      Sensors Contest

    7 Discussions


    5 years ago

    I built it, and it worked the first time! the specs on the capacitors are very loose, so you don't have to use the exact value listed.


    5 years ago on Introduction

    Hi I'm following the instructions not using the 3d parts, when i attach the led to the circuit with the battery it emits light and when i attach the batter to the led circuit it emits light but when I attach the battery to the circuit and try to use coils to transmit the power it fails. Any ideas what's wrong?


    5 years ago

    schematic please?

    sorry but i must pick a hole in your fourth line, wireless electricity is certainly cool and exciting but not at all new, this principle has been known since the earliest crystal radio sets. what you have here however can trace it's origins even further back though, it looks to be effectively an AC-AC transformer with the coils separated by a distance, the changing magnetic field in the supply coil creating a changing flux on the output coil hence a voltage. not new but pretty cool. one thing you really ought to do is test the voltage being created in your output coil at various distances from the supply coil, i'm guessing it will follow an inverse square law.


    Very nice project, but I have a question, isn't its function the same as an air-core transformer?

    1 reply

    Not exactly, various people have transferred electricity wirelessly on a somewhat longer range. Tesla was the pioneer on this. One group, MIT I believe it was, also did some work on this so that there was a room with transmitters that would charge your cell phone (cell phone had receiver coil) whenever you were in the room.


    5 years ago on Introduction

    I think that you may be better off using enameled wire because the coating is thinner so it has less insulation to go through.