Built in late May of 2001 the Mk-1 Prototype was a small array of 20-40 caps that Mark Broker used to perform the electrical engineering and design work for what would become the final array. Mark tested out several different combinations of series and parallel configurations to see what setup would yield the best results. He also did a lot of engineering on various charging systems and in the process invented what would come to be known as the "Broker Enhanced High Voltage Safety Switch" which an amateur may mistakenly refer to as a bit of string and some thick cable.

The original setup at Sigma-6. The interconnects were made from pieces of 6AWG that was un-stranded in specific places to make holes for the capacitor terminals to pass through. everything was held together with tie-wraps donated by Panduit. There was no metering at all and charging was done through the use of the original CB-1 control cabinet (it would later see use as the main control cabinet for Gemini for several years). To know the charge state someone would hold a pair of probes on a set of terminals and call out the charge state to the person operating the power supply across the room.

Here you can see the "Broker Enhanced High Voltage Safety Switch" very clearly.

The initial idea was to experiment with using the array as a way to crush soft drink cans as a demonstration in electromagnetometalforming (there's your nickel-word for the day). Mark performed several experiments with different array configurations to this end.

Though the results were less than impressive given the energies we were working with. Mark and Chris were thrilled that it worked at all. The rise times are much lower (an order of magnitude or more) than a typical pulse capacitor system because we're using Electrolytic's instead of true "Pulse Rated" capacitors. Many people told us that any manner of can crushing would be completely impossible.

Turns out they were mistaken. Here is Mark with his freshly crushed (and still quite warm) can.

It was time to take things to the next step and build a larger prototype.