Greg Leyh, aka Lightning on Demand, has been working on a 17-foot-high Tesla coil, the largest operating Tesla coil in the world. He began building the device in 1990 with parts from an Oakland scrapyard and used it to disable “hostile machines” by cooking their electronics. The upgrades since have been largely focused on boosting the output current sent along its output arcs. This involves synchronizing a large boost in the device’s primary with the moment its arc touches its target, creating a channel of conductive plasma through which dangerous amounts of current can be discharged. Leyh demonstrates the effects of a boosted pulse on an incandescent light tube, which resulted in a loss of structural integrity and a liquefefying of the power supply. The machine currently operates a working range of about 30 feet.