555 Audio Modulated 20kV Flyback

Audio Modulated Flyback Transformer

pulsed DC high voltage using 555 timer






This is the circuit I followed.  The only changesI made were:

– instead of 10k and 9k pots I used what I had on hand, I used two 50k pots.

– I also used a IRFP260N, not the 250N.  I’m sure the 250N works just fine though.

– the 50R resistor I just used a standard 100ohm 1/4 watt resistor

– I used 6 windings of solid insulated copper wire




The flyback I found was from an old Dell CRT computer monitor.  It is a samsung flyback.  I highly recommend when doing this that you have a very loud audio source, a single 12V battery (although you can test it with a simple 9V), a heat sink and thermal paste to glue the power MOSFET to.  If you have all this, you should have no problem having success early on.   Once you test everything out with alligator clips, you should go ahead and solder the wires because the high voltage will easily fry the insulation in tiny alligator clips.




WARNING — the flybacks ALL have high voltage capacitors inside them, you MUST discharge the flyback before handling it, it’s pretty painful if you don’t.


Once you have the driver circuit up and running, you should be able to simply take the thick red wire from the flyback (it might have a suction cup thing on it) and bring it closely to some of the exposed leads of the bottom, you will easily find several that spark with a very high pitch squeal, but one of them will be very very strong.  That is the GROUND (-) you will want to solder or clip to a longer lead and get it far away as you can.  One thing I noticed while kitting this thing into a box was that it will arc pretty easily up to about two inches.


Once you find the ground, you’re done.  Attach the leads and then do whatever you want with your new toy!!  Things like:


– fry anything

– light up compact flourescent light bulbs from about 6 inches away


The audio portion like I suggested get a loud amplified source like a jambox or stereo system.  Your iphone / ipod won’t push out enough voltage.  You have to amplify the audio!!!  The 555 driver circuit will work without an audio signal, it will just be a spark with a high pitched squeal.  Once you plug in the audio signal, you might have to adjust the pots to get the best push from the driver circuit.  The 555 circuit has a threshold and a discharge pot, so twiddling those somewhere in the middle worked for me.  The extremes didn’t work well.  If you have the heat sink and power source in good shape, it will run easily for long periods without over heating.  If you have a good connection, you should ONLY hear music and very little, if none, static.