Simple plasma globe lighting tube.
Here I took a capture from my web cam. Quality is not good but at least you can see it working. You may want to save the pic and lighten it up a little...
To the right is the Plasma Globe running. It is a 8" globe running from 12V 500ma wall transformer. On top is a large toroid. To the left is the tube. It is connected to the toroid one end and the other end is connected to a local ground ( house radiator in this case ) which works well. The tube is a 13watt type. I did try some 8 watt tubes but the 13watt seemed to light the best. The tube itself is faulty and will not light under normal conditions.
I now try the tube with no toroid ontop..
The tube is actually just touching the edge of the globe and also lights up bright when held at the other end. Its hard to see but it works better slightly with the toroid and ground connection.
Now I tried holding the end tube connection ontop of the globe to see if there is any effect.
In this case it worked but not very bright at all.
For a final test I move the tube away from the globe..
Again it lights but not very bright.
It is clear that connection from the globe with a toroid works best. I see that the toroid is connecting to the globe on a wider area and holds more charge. I also noted that when you place your finger right next to the toroid you can draw off small sparks from it. This does not hurt though the spark will burn you finger if you leave it there for more than a few seconds.
The globe can also light up other things aswell. It will also light neon bulbs and even LED's with much the same effect. With the LED tests you can place the toroid or even a small piece of tin foil next to the globe ( on the floor ) and when you touch the LED on the foil it lights. You can either hold the other end of the LED with your fingers or connect to ground.
I also tested this with charging small capacitors. I found that .47uF 63volts, would charge to about 25 volts in 1 second. I had a bank of these "charging" circuits and managed to flash brightly a LED every other second. I also tried some 100nF 250volt caps which also charged up well. They of course gave me a bit of a shock when I touched both legs :-\
I also tried a bank of capacitors in series and measured a rise upto around 2,000 volts. I used a series of .10uF caps in this test. The voltage was still rising fast at 2,000 volts though my meter wouldn't go any higher so I couldn't see just how much voltage rise I could get. They also made a nice flash when shorted out :)
Going by how dim the LED's were I would guess there to be very small current there. I would guess at 0.100ma. Someone might be able to work it out better from the capacitor info I gave.