WARNING: This article deals with high voltages, glass items and other fun things! The author is NOT responsible for any damage you do to yourself/others or whatever mischief you do. Do this at your own risk!!! I take no responsibility for your incompetence!
NOTE: If you decide to build one of these, feel free to do so. But PLEASE: Send me a photo, I'll publish it here, with a link to your site.
Basically, a plasma ball or lamp or however we decide to call it is a glass sphere/other shape filled with very low presure gas (ussually neon) and a tesla coil (or any similar resonator based power supply) or other high voltage power supply with AC high frequency output. In theory it is very easy to make one, if you have access to low presure neon pumping facilities, custom made glass and a tesla coil. 😉 The scientifically more correct explanation of how the plasma ball works can be found here. The father of the whole plasma ball is Nikola Tesla. So treat it with respect.
Now. To avoid buying thousands worth of gas pumping equipment and a glass manufacturer I decided to look for alternative sources of low presure gas filled glass items. And guess what! A nixie tube! The basic principle of the nixie tube is an inert gas discharge, where the gas becomes conductive at low presures and high voltages and even glows! That's why nixies work and have that beautiful warm glow surrounding them.
A close look at the contruction of a nixie shows that it's full of metal, which is conductive and connected outside.
For a high voltage power supply you'll need a neon driver from a PC tuners shop. They are basically tesla coils fitted down to an output voltage of approx. 750V AC. Like this one:
For making the plasma balls body, you'll need any nixie tube you can get, but you should make it a big one. I'm selling a few smaller ones, but I'm not giving up the Z560 I used here:
You can see both the high voltage power supply and the nixie tube. So, here are the steps to making a plasma ball:
1. Remove the filter covering the nixie from its surface: Neon emits a quite wide spectrum of colors when you discharge through it. Red, blue, most likely others that aren't visible. But to view numbers on it a filter layer was added to remove these. It's ussually a simple red colored paint. Nothing a good brush and hot water can't hadnle! Be cautions not to scratch the glass surface!
2. Connect ALL of the nixies outputs together: Simply solder them together. Not much to say about that. It will ensure that all parts of the nixie have equal potential.
3. Connect it up! Use this schematic. It will require minor modifications to the HV power supply: These power suplies ussually have a capacitor on the output. I'm not sure why. Anyway, bypass or permanently short circuit the terminals of the capacitor. You CAN use an unmodified one, but you'll not get such good results. Also, the high voltage ground and the main ground of the main power supply MUST be connected together! Warning: from now on you are dealing with high voltage! Click the schematic for a better resolution.
4. Connect it to +12V! And you're of! Enjoy the warm glow of the nixie! DO NOT TOUCH ANY CONDUCTIVE PART, ONLY THE GLASS!!!
Here are some photos of the nixie being touched by me. Enjoy.
My friend Gabo constructed this one: