Sunday, September 2, 2012

First test with eBay x-ray tube

 I found an X-ray tube on eBay and fired it up with my Spellman high voltage supply. I ran the tube at about 35-40KV at 180uA. This required a filament current of about 1.5A at 2.5V DC.  With the room very dark, I could clearly see the phosphorescent screen glowing green. It wasn't bright enough for my eye to discern details in the X-ray images, but the camera with a 4 second exposure at f/5.6 and ISO400 was perfect. I took some pictures of various electronic components. I also X-rayed a dead, dried-up bumble bee, and it produced no image at all! The X-rays completely penetrated the insect without any visible absorption. I should have turned down the anode voltage, but I didn't think of this until after I threw away the bee.
The tube is a Nago GFH2-0.3-85-60


  1. Very cool. Are you sure that thing is safe to be around without any shielding?

  2. Jake, I was shielded by 1/16" lead from direct beam exposure. The Geiger counter was mostly detecting backscatter X-rays. For a short experiment, I don't think the dose is anywhere near a problem. I wouldn't make a habit of doing this, though.

  3. What is the name and model of the x ray cassette in that video?