In this article, I'll show you how to built a Wireless Transfer of Energy Transmitter. Simply put, this device will send electricity to a florescent light bulb and light it up, from up to three feet. The idea originally (at least, prominently) came from Nikola Tesla (read more about this amazing inventor here), who used his Tesla coils to transfer wireless energy to light bulbs in demonstrations (photo below). However, the circuit described in this article consists of a flyback transformer, not a Tesla coil. They are similar in windings (large ratio between secondary and primary coils) and operation (both step-up voltage). However, Tesla coils have air-cores (no core) and flyback transformers have Ferrite cores. The components for this project can be extracted from most tube TVs.
To build this device, you'll need:
- An old tube TV (or, if you have the parts available, a flyback transformer, a power NPN transistors, a 220 ohm resistor rated at 1/2 a watt, and a 27 ohm resistor rated at 2 watts)
- A fluorescent tube
- A 2' piece of 13 gauge wire
- A soldering iron
- Flux-core solder
- A protoboard or similar circuit mounting hardware
- Wire cutters
- Some screwdrivers
- Insulated wire
- A voltmeter
Once you've opened up your TV, you should first cut the large red wire connecting a suction cup to a large black "thing"; the flyback transformer. MAKE SURE you use insulated cutters! Now, using a large piece of insulated wire, discharge the flyback transformer by shorting the red wire to any ground. The flyback transformers tend to hold a charge, similar to that of a Leyden jar. Its always a good idea and safety precaution to discharge them, even though its unlikely to be a lethal shock. Now, desolder the flyback transformer from the TV circuit board. Once extracted, it should look like this:
Now for the tricky part, identifying the pins. Set your voltmeter on "beep when shorted" and start testing the pins. Once your voltmeter beeps, check out the resistance. If it's around .6-1, you've found your primary coil. Solder two wires to those terminals and leave them lose for later on. You now need to wrap a feedback coil, which consists of about 6 turns of insulated wire on the outer ferrite core. Once finished, it should look something like this:
The circuit itself is quite simple. An NPN transistor switches the electricity through the primary coil, depending on the input from the feedback coil. Imagine turning on and off a light, depending on if the light is on or off. In other words, when the light is off, you turn it back on again, but when its on, you turn it off. This creates a fluctuating magnetic field, which in turn generates electricity in the secondary windings. To learn more about electromagnetism and transformers, check out Electromagnetic Weapons. To build the circuit, extract the NPN transistor from the TV circuit (it should be the largest one on the board—keep the heatsink it's attached too as well). To check and identify the pins, turn your voltmeter to the diode setting and follow these steps. Once you've identified the pins of the transistor, identify and desolder the 220 ohm resistor, and the 27 ohm resistor. Finally, build the circuit below:
When finished, test it out CAREFULLY! The red wire should arc to a pin on the flyback transformer. This pin is the ground, note its location.
Take the copper wire and bend it into a large loop. This isn't critical—feel free too experiment with the shape of the antenna. Now, solder the red wire from the flyback transformer to the copper antenna. Mound the entire circuit, transformer and antenna on something (like a plank or box etc). Solder a long wire to the ground of the transformer (noted above) and attach that wire to a grounded conductor (like the ground on the average wall socket). Basically, the electricity travels from the transformer through the antenna, then out into the "air". In the dark, this will be seen as something called corona loss, a dark blue "haze" of sparks flying off the antenna (BE CAREFUL, these will shock you if you come to close).
To use the device, grab your florescent light and turn on the Wireless Energy Transfer device. When you bring the florescent light close to the antenna, the light should glow. If you're interested in other things to do with the device, hanging multiple florescent lights from very thin copper wires attached to the roof is quite amazing. When the device is turned on (and close to the florescent lights), they turn on! In the dark, it gives an ominous, floating light look. Great for Halloween displays or simply impressing the neighbors :)
- HIGH VOLTAGE is dangerous!! Don't electrocute yourself.
- Soldering irons are hot! Don't burn yourself.
- I am not responsible for any danger or harm you cause.