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Photographic plate for X-rays

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c4r0

Sat Nov 18 2006, 08:18PM

Registered Member #151 Joined: Sun Feb 12 2006, 02:53PM
Location: Poland
Posts: 153

uzzors wrote ...
Where do you get all of that stuff anyway? On the internet, ham- get togethers, people you know? 3USD for an x-ray cassette is amazing!

Actually, 3USD was for only screens (not whole cassette). The auction is finished already but the website is still available:

I bought the fuji cassette on the internet auction too, but for about 25USD. Recently, I sold it for 50USD, hehe

I found the x-ray head (

, Sorry about all 'English text under construction.' on my site

) about one year ago on a hospital backyard (i was visiting my grandma). It was laying in a shrubbery. At first i thought it's an electric motor or something like that, but i noticed a "100kV" caption on it

Then i knew that it's something interesting

It turned out that it was laying there long time and they was going to throw that away and i could take it

Cool, isn't it?

Avalanche

Sun Nov 19 2006, 01:08PM

Registered Member #103 Joined: Thu Feb 09 2006, 08:16PM
Location: Derby, UK
Posts: 845

c4r0, where you have connected that vacuum tube to your coil to produce xrays you don't appear to have the filament connected up in the tube, am I right in thinking that your using the Tesla/Bremsstrahlung method of producing x-rays? (i.e. no target electrode in the tube

)

Just wondering, because I might try it myself if it works that well.

As for making the screen, my recommended method is to rub the phosphorescent powder into the sticky side of sellotape or self adhesive book covering to produce a light, even coating.

c4r0

Sun Nov 19 2006, 08:02PM

Registered Member #151 Joined: Sun Feb 12 2006, 02:53PM
Location: Poland
Posts: 153

Avalanche wrote ...

c4r0, where you have connected that vacuum tube to your coil to produce xrays you don't appear to have the filament connected up in the tube, am I right in thinking that your using the Tesla/Bremsstrahlung method of producing x-rays? (i.e. no target electrode in the tube

)

No, i'm using both electrodes, one is connected to sstc output and second is grounded. But filament is not connected indeed. It works like a not heated coolidge tube.

uzzors2k

Mon Nov 20 2006, 02:36PM

Registered Member #95 Joined: Thu Feb 09 2006, 04:57PM
Location: Norway
Posts: 1308

I gathered my first sample from a 15inch monitor, looks like a few grams. The anti-implosion setup they use really works! I just put the monitor in a plastic garbag bag and dropped it on the floor, and the bag didn't even rip! The entire tube did collapse though..

Does a flyback spark produce enough UV to see if it will fluoresce? Otherwise I can't really test it.

Marko

Mon Nov 20 2006, 02:41PM

Registered Member #89 Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145

It definitely flourescences under UV, and it seems pretty wide range; it lookls like it should be suitable for xraying.

My TV and monitor give pretty bright output even thouugh glass, 'powered' from one UV LED.

Wolfram

Tue Nov 21 2006, 10:03AM

Registered Member #33 Joined: Sat Feb 04 2006, 01:31PM
Location: Norway
Posts: 971

How about using the entire front face off a small/medium monochrome CRT as a fluorescent screen? Is there any reason why this should not work?

A.M.

uzzors2k

Tue Nov 21 2006, 11:00AM

Registered Member #95 Joined: Thu Feb 09 2006, 04:57PM
Location: Norway
Posts: 1308

I was thinking about that, but it would be quite difficult to get the face of the crt out in one piece. If it doesn't shatter, all the phosphor will be sucked off when it implodes anyway. Which is exactly what happened to one of my monitors, the face barely shattered, despite being dropped face-first on the floor, and yet all the phosphor was gone!

Anyway, I got a descent yield from the other 2 monitors.

Marko

Tue Nov 21 2006, 12:41PM

Registered Member #89 Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145

You can try to slowly let the air in through high-voltage connection plate by carefully drilling it
(although this looks much more dangerous to me than previous methods.
Some people did this and used tube as gas-evacuator for various tube stuff.

Then you could carefully smash off the gun and back of tube.

uzzors2k

Tue Nov 21 2006, 01:48PM

Registered Member #95 Joined: Thu Feb 09 2006, 04:57PM
Location: Norway
Posts: 1308

I'll have to try it later sometime, luckily its not hard to find free monitors!

If i can't make a good x-ray screen with the phoshor powder I'll try this. Drilling sounds difficult to acomplish without causing the tube to collapse. I think it would be safer to somehow break the stem off from a remote location, pistol maybe?

Marko

Tue Nov 21 2006, 02:14PM

Registered Member #89 Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145

Crt's actually may not implode if the gun is carefully broken away.

I remember once, when we (foolishly) left an open TV in garbage wth CRT pointing upwards, it came to this that somebody throwing garbage on it or etc. just snapped the gun part away and nothing happened.

Most modern CRT's are actually suppsed to survive unless they get a direct hit into screen, wich is usually especially hardened

Problem is, that even if yu do that, the inrush of air is probably going to blow off some phosphor anyway.

Some people here may have experience in 'careful' opening of CRT's, so I guess you should ask them...

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