The CFL Flyback Driver

Since all you lazy fucks didn’t want to build a ZVS driver, here’s a way to make high voltage easier.

First you will need a flyback. These are the transformers that make the high voltage in CRT displays. [The big heavy glass ones]. The flyback will look something like this. You can remove it from the circuit board with a blowtorch; simply apply the flame to the solder and it’ll come right out. Don’t worry about burning the board.

Now you need to identify the primary coil of the flyback. On the bottom there will be a semicircle of pins. To identify the primary coil, use a multimeter to test the pins. When you find two pins that measure about .5 to 2 ohms, that’s your primary coil. Mark those pins so you don’t forget.

Now you need a CFL. A compact florescent lamp is one of those swirly lightbulbs. Get a big one, the bigger it is the more powerful your driver will be. They are usually anywhere from 14 to 60 watts, but once more, the bigger the better.

Step one is to crack open the CFL. Try not to break the bulb, you just want to crack open the plastic. Inside you will find the driver. It will look something like this. This is the circuitry that supplies few hundred volts to the light bulb.

Now all you do is wire it up like this;


That will provide the transformer with the high voltage, high frequency AC it need to run. If all goes well then a few thousand volts will come out of the red wire. But to use it you will need to find the high voltage ground. The easiest way is to just bring the wire to the pins and see where it sparks to, but then you risk killing the CFL driver. A better method for finding the HV ground is here. If you don’t have a 24 volt power supply, use 3 9 volt batteries in series, or two car batteries in series.

If you’re lazy you can just arc to the flyback’s pins, but once again you risk killing the driver. Use a rubber glove or plastic tweezers when handling the thick red high voltage wire!

Once you find the ground pin, solder a wire to it. You now have your high voltage supply. It’s safe to handle the ground wire with your bare hands; it has no potential.

If all goes well you should have;

Is something not working?

A)You wired it wrong, or your driver has a different wire config. Try different combinations of wires.

B)If none of the 8 possible combinations work, then you have a protected circuit. These circuits shut off if they don’t sense a lightbulb. This is easily defeated by placing a high voltage capacitor (400+V) across the two unused wires. You can get those at radioshack cheaply, and any value will work so long as it can handle more than 400V.

C)If that didn’t work, try connecting the capacitor between an unused wire and one of the used ones. Try the 4 possible combinations.

D)If none of that worked, go get a different CFL.