Richard Nakka's Experimental Rocketry Site. Marx Generator. Update May 2003 - Marx Three is now up & running Do you like the idea of tesla coils and other high-voltage sparking stuff, but don't have the time, money or patience to build something that elaborate?
Here's a fun little project that can make big, fat, noisy sparks at least 2 inches long, and can be built very quickly and cheaply. The Marx generator consists of an array of resistors, capacitors and spark gaps arranged as follows: The capacitors, C, are charged up in parallel via the 1M (one megohm) resistors, so they each become charged to the input voltage. When first (leftmost) spark gaps breaks down (sparks), the voltage across the next increases, causing it to break down, and so on for all the other gaps.