Marx Generator

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The Marx Generator is a nifty way to charge up capacitors in parallel, and discharging them in series. Therefore, you get more voltage and bigger SPARKS!

Below is the schematic diagram

There are six stages using .002uF 20kV ceramic disc capacitors and 1Meg ohm resistors between each stage. The transformer is a 9kV 30mA neon transformer that is rectified by a string of ten 1N4007 diodes for a 10kV 1A rectifier rating. The DC charges up the generator and when it fires, makes loud 1.5-inch snapping arcs. This Marx generator fires once every 2 to 3 seconds.

The Marx generator

1.5" Sparks

UPDATE! The "quick and dirty" marx generator shown above has been rebuilt in a neat manner on a small wooden platform and now runs off a compact high voltage generator. The HV generator consists of a 555 timer oscillator that drives a HV transistor, which drives a small modern TV flyback capable of providing about 12kV to 20kV. Below is a schematic diagram of the updated marx generator with the new HV generator.

The transistor I used was found in a junk pile, and if my sources are correct, is rated around 400V 8A. However, the transistor and the big heatsink got very hot while operating over 30 seconds, so I added a small laptop fan on top of the heatsink. 2.2Meg 1W resistors were used. No external rectifiers were necessary since the modern flyback already provides DC (diodes are built in). This generator fires about once every second. I could push this generator to give over 3 to 4 inch arcs, but then the resistors start arcing and the leads on the capacitors sometimes arced - so I brought the arc distance back to 2.5 inches and it performed well without problems. Below is a picture of the updated marx generator in operation (FYI: it fired twice while the camera's shutter was open).