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Make wireless electricity easy with this simple DIY!

This project will use the principle of magnetic inductive coupling to transfer electricity between two separate coils.

Step 1: Materials

Overall, this experiment does not require too many materials, many of which can be easily acquired.

The materials are as follows:

  1. 30 gauge magnetic wire
  2. Alligator clips with leads
  3. 2N2222 NPN-Type transistor
  4. Electrical tape
  5. Low-power LED
  6. Measuring tape
  7. Scissors
  8. Pliers/wire cutters
  9. Battery (9V)
  10. Soldering gun
  11. Solder
  12. Cylinder with 2cm diameter

All of these materials can be found at local hardware stores and specialty stores such as RadioShack.

Step 2: Building the Coils

The first step in transferring wireless power it to make the coils. The two coils consist of one inducer and one receiver coil. They are made in the same manner, except the inducer coil will need a center tap.

Step 3: Inducer Coil

To build the Inducer Coil, measure out 3 meters of 30 gauge magnetic wire. Then take the cut wire and begin wrapping it around your cylinder, leaving a sizable lead. After about half of the wire has been used (about 15 turns) create the center tap. This is done by pulling about 2 cm of wire away from the coil and twisting it. Do not cut the wire! Next, finish wrapping the wire around the cylinder, leaving another lead. To prevent unwinding, put 3 pieces of electrical tape on the coil. This will not effect the overall electrical output. You are now finished with the inducer coil.

Step 4: Reciever Coil

The receiver coil is made like the Inducer coil, but without the center tap. To accomplish this, simply keep winding the coil without stopping.

***Helpful tip: Scrape off the enamel coating on the wire to ensure a good connection.

Step 5: Connecting the Transistor

The transistor is the brain of this operation. Its purpose it to connect and disconnect the power at a rapid pace, thus creating a changing magnetic field in the inducer coil. This changing magnetic field is what induces an electric current in the receiver coil; which powers the LED.

To properly connect the transistor, you need to attach the correct coil leads to the correct transistor terminals (emitter, base, and receiver). The transistor will be soldered on.

Emitter will go to the negative of the 9V battery

Base will go to one inducer coil lead

Collector will go to the other inducer coil lead

Simply solder the terminals directly to the leads, and the connection will be secure.

Step 6: Connecting the LED

The LED will be soldered to the two leads of the receiver coil. This allows the LED to be powered easily when the receiver coil is moved around the magnetic field. Each LED terminal will be connected to one lead of the receiver coil. The positive and negative of the led do not matter, as the current in the receiver is changing.

*** Helpful tip: trim the ends of the LED terminals so that it does not awkwardly stick out from the receiver coil

Step 7: Connecting the Power Source

This experiment is powered by one 9V battery

Emitter will go to the negative of the 9V battery

Center Tap will go to the positive of the 9V battery

The full project can be represented in the schematic above

***Helpful tip: only connect the power to the coil when it is in use, as long periods of connection will deplete the battery and may fry the transistor. One way to solve this problem would be to connect a 100 ohm resistor to the base of the transistor (suggested by Majstor_nizasta), but since this project is supposed to be as simple as possible, I didn't include it.

Step 8: Wireless Power

Once everything has been assembled and the power connected, hover the receiver coil over the inducer coil and watch the LED light up; without wires!!! I recommend experimenting with different positions and distances, as it is lots of fun. You can even place items between the coils, and the LED will still be powered. Also try flipping the receiver coil over if the LED is not very bright, as the magnetic flux of the receiver coil flows in one direction. The platform (black rectangle under the coils) is not necessary, but it allows you to move the whole project around more easily. It is simply the inducer coil glued to a note card wrapped in electrical tape.

Thank you for viewing, I hope you enjoy this as much as I have. And don't forget to vote this as you favorite and share it with your friends.

To learn more about the physics behind magnetic inductive coupling and wireless power, I recommend researching Howstuffworks, The Wireless Power Consortium, and Witricity.

I also highly recommend you read, the comments, there is some great information on completing this instructable thanks to all the amazing supporters!

<p>Greatable, You earned my votes!</p><p>Thank you for this post!</p>
<p>I'm glad you enjoyed it. Thanks for your support!</p>
<p>will copper magnetic wire work</p>
<p>Yeah, for sure!</p>
<p>This is really cool and i cannot wait to make one myself and test it ! Great work dude.</p>
<p>This is by far the best instructable in this contest.</p>
<p>Hey this is a great project, It was fun to do. How can I increase the voltage output to around 5 - 10V at a range of about 2cm</p>
<p>Could make / buy a simple buck-boost circuit, check out &quot;Joule Thief&quot; then go make one and add it to the receiving end of your circuit ;)</p>
what is the frequency of oscillation produced by the transistor ?
<p>You can use relatively simple physics equations to determine the frequency, your variables being: how many turns your coil(s) have, the value of the transistor, voltage, amperage, etc. If you are still interested I can point you in the right direction :)</p>
<p>will 26awg wire work</p>
How high of a voltage should my led be
<p>I made the circuit and I decided to put it together using jumper cables to make sure it worked before I soldered it. When I hooked it up to the 9 volt, it made sparks when I touched it and then I connected it. It worked for like a second and then it faded away. The inductor coil was warm and the transistor was so hot it burnt my finger! What might I have done?</p>
Wow! It sounds like you have too much power going to the transistor and you fried it. This actually happened to me once and I found out the the 9v I was using was 6 amps instead of the standard 0.5. If that is not the problem, I would recommend using a resistor
<p>ok good</p>
<p>Thanks for the great post!</p>
<p>Hello, how can i increase the distance about 10 cm and up between transmitter and receiver?</p>
For that distance you will need to change your power source and add capacitors, I can refer you to a few schematics.
<p>Me too plase</p>
<p>This is a good step-by-step procedure, and the illustrations are clear and easy to follow. </p>
Thank you!!
<p>This is a good step-by-step procedure, and the illustrations are clear and easy to follow. </p>
will any NPN transistor work for this experiment?
<p>Ok, so I have 28 turns of 30 Gauge magnet wire and a tiny green LED for my receiver. I have 14&amp;14 turns of 30 gauge magnet wire connected like yours with a very similar transistor. Connecting the battery and positioning them produces nothing. What am I doing wrong? I can add images if that would help.</p>
Please send images, that'll be the best way to find the problem
<p>I found out I was supposed to be looking at the transistor with the rounded side facing me. I had the terminals backwards (CBE instead of EBC). Noob error, I know. Now it choo-choos correctly, though weakly. </p>
<p>I found that mine wasn't bright enough.<br>i was using 15+15 turn for inducer, and 50 turn for reciver.<br>i use 0,12mm brown wire(i've took it from speaker coil).<br>does my wire wasn't big enough?<br>srry 4 bad english.</p>
That could be the case
<p>It's an interesting project.. But i was thinking to use it as a phone charger.. Do you have any suggestions. </p>
That's a great idea, my suggestion would be to up the power and then get a USB power converter from amazon
<p>How does the transistor connect and disconnect the power at a rapid pace?</p>
It pretty much works a switching transistor, that's just an easy way to explain it, the actual physics are a little more complex.
<p>will 29 gauge wire work </p>
Can you explain the actual physics please?
<p>So I have this built using a 9 volt battery and a rectifier connected to the receiver to convert back to dc power, but I want to use this on my 12vdc 2a power supply. I'm using a 2N3904 transistor, and I want to know if there will be a problem with amperage or base voltage with max being 5 volts on the base. I know a circuit only pulls what it needs, but I just want to be sure because I only have a few transistors.</p>
It doesn't sound like there should be a problem, I'd just make sure the transistors don't get hot, I broke a few that way. Just touch them when everything's hooked up to make sure they're not hot.
Can i add a 12V battery?
<p>You should be able to, just make sure to include a proper resistor. To answer your other question, I'd increase power (e.g. a 12v like you said), and increase the number of coils. I even experimented with capacitors which can tune the coils to the same resonant frequency, thus increasing range.</p>
<p>I am using BC548 transistor, but it is not working, can you please tell me why ?</p>
<p>That transistor might not have the same &quot;switching&quot; properties that induces an oscillating current. I'd stick with an NPN 2n2222 or NPN 2n3904</p>
<p>I was dubious about this project. How surprised and pleased when it worked first time. I am amazed by this. Well Done. A great ible.</p>
<p>the resistance value resistor you use?</p>
<p>While there isn't a resister in the picture, I later found 110 ohms is a good start.</p>
<p>you can make video. i'll try, but dont work. please help me</p>
I'm glad you made it, thanks for your support!
<p>can you give me send PDF document about this &quot;simple wireless power&quot;? please<br><br>i hope you send me this procedure doc. my email= Asrorthefirst@gmail.com</p>
<p>I believe you can just download the PDF strait from the Instructable.</p>
WHAT COULD BE A GREAT ALTERNATIVE 2N2222 NPN-Type transistor? I COULD NOT FIND ONE IN OUR PLACE...
<p>A NPN 2N3904 also works but that's about it for transistors. You could also use an oscillator if you own one ( I don't so I didn't use one) </p>
<p>any thing else?</p>

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Bio: I enjoy making and reverse engineering simple electronic circuits and devices. I hope you enjoy my instuctables, and more will be coming out soon!
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