Radioactive Source for testing a detector

In the process of developing my low-cost Cosmic Ray Detector (Muon Detector) it has become increasingly clear that I first should confirm that a common fluorescent lamp can be used to detect radioactive particles when placed between a high voltage electric field.

Although the idea has been demonstrated in a simple experiment describe at the High School Teachers CERN lab and the CosmicRays.org website, the detector described relies solely on visual confirmation of faint flashes over multiple tubes.

Where my muon detector relies on the assumption that a current draw can be measured in the high voltage supply, when the gas inside the fluorescent tube ionises. Consequently, it will be very important to see if under controlled conditions a radioactive particle will trigger such an effect.

Basic Test Schematic.

Unfortunately, I haven’t yet been able to source a radioactive sample to use in a test, as there seems legal restrictions in Australia that prevent amateur experimenter owning such samples, nor putting them through the post even with a weak level of radiation.

I have even visited numerous antique stores with my Geiger Counter looking for uranium based ceramics or glass without success, well nothing that is good enough for testing. But I have had many strange looks and questions when I pull out my pocket Geiger Counter.

So I build a low-level x-ray source using a Vacuum Tube and high voltage ~50KV. Although slightly more dangerous an xray source can be switched on and off at the flick of a switch which has een bvery useful for testing the detector.