Jacob’s ladder: 10,000 volts of fun
I picked up this transformer somewhere (yardsale maybe), its made to run the ignitors (like big spark plugs) in an oil burning furnace.
I decided to make a jacob’s ladder out of it (you know, like in the horror movies, an arc strikes between 2 rods, then climbs). I threaded a couple inches of the ends of some 3/16 brass rods, crudely bent them, and threaded them into a puck of scrap PVC. I can rotate them to adjust the minimum arc length.
Here’s the arc after it has risen. The arc strikes at the closest point, but heats up the air inbeween. That air rises, but because it is ionized, it has less resistance than the lower, closer gap. The arc rises until the distance gets too great, then starts over again.
Click here to see a jaw-dropping video of a 20′ arc rising to 100′ at 500,000 V (1.5mb mpeg video), via long arc.
