Greg's Homemade Plasma Globe Page

Email: sixmhz@yahoo.com
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I'll start off with the plasma globe driver. It is a single transistor driven flyback transformer. You can find all the information on the construction of such a driver on the FLYBACK page linked through my homepage. This particular flyback transformer came from an old mac monitor (parts are probably the best use for mac stuff) that I found outside the chemistry building at the University of Iowa. The monitor was pretty old. Old enough that the potted rectifier stuck out enough for me to hack it off with a saw. That was a mess! So the output is AC, not rectified, which is essential for a plasma globe. RF current is nessisary because the glass 'globe' does not pass dc current (like a capacitor). The input is 12 VDC and the output is probably near 20kV AC. Here's the photo:

We used a 250 mL round bottomed flask for the globe itself. In order to evacuate the globe, we needed a good tight seal and a way to valve off the pump so that we could hook it up to the AC power. We did this by constructing a simple insert using 1/8th inch swagelok pipe, a rubber stopper and a brass valve. Here's the insert and Tom drilling the hole through the rubber stopper.

Before we evacuated the globe, we filled it with noble gas. We tried Krypton, Helium and Argon. Argon seemed to work the best and air worked very well, too. We pumped down to say around 10 torr or so (we could get water to boil at room temp). Here's a photo of the pump we used:

After pumping, we valved off, disconnected the pump and hooked up the high voltage. Viola (I like Wala better)! instant plasma globe! The globe filled with arcs of purple plasma that would follow our hands around.

Last updated: 6/22/02
Copyright 2002, Greg Miller
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