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Registered Member #2099
Joined: Wed Apr 29 2009, 12:22AM
Location: Los Altos, California
Posts: 1714
Nice pics. Do you know how to edit an old post, to add a new picture?
Please share some qualitative (Geiger counter) or quantitative measurements of x-ray leakage from your enclosure. If "practically zero" then I would induce a small leak to be sure the instrument is working.
I seem to have overlooked any posted diagram or picture of your system. We'd love to see the placement of x-ray tube, subject, fluor. screen, viewport, camera...
Good thing your Coolidge tube does not overheat during long exposures. Do you have any sort of heat sink on the anode? Does natural air convection keep the anode temperature (at glass seal) tolerable? For systems that depend on thermal inertia, many tubes are rated in "heat units". Those are like joules (kV * mA * s) with a scaling factor for nominal x-ray voltage (which is peak) and current (which is average) in mains-frequency operation.
-Rich
p.s. one of these days I need to get a DSLR camera. What are you using?
[edit] As a rule, commercial enclosed x-ray systems have safety interlock switches to prevent operation with the door open. Just like microwave ovens. For example, in case an enthusiastic operator, working close to a deadline, becomes drowsy.
You looked from behind to the screen? So, your DSLR is exposed to the x-ray? I am currently setting up something similar, but with a pulsed device with 150 kV and later on with 500 kV (field emission). But I want the DSLR to look to the screen via a mirror because the DSLR probably does not like the radiation
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