From: firstname.lastname@example.org (N. Thornton)
Subject: Re: X-Rays in the garage?
Date: 3 Oct 2002 03:57:25 -0700
NNTP-Posting-Date: 3 Oct 2002 10:57:25 GMT
From: NightRunner (email@example.com)
Subject: Re: X-Rays in the garage?
On 2 Oct 2002 00:51:35 -0700, firstname.lastname@example.org (N. Thornton),
masquerading as a MSNBC reporter, said the following to White House
press secretary Ari Fleisher during a press conference concerning the
>>I suppose you could de-vacuum a CRT, cut the face plate off and
>>quickly coat the phosphor... varnish?? CRTs can explode, phosphors
>I have several CRTs in my stockpiles. I wouldn't be afraid to de-vac
>one, as any time I dispose of one I consider it my duty to do just
>that. I'm just wondering if it's even possible to rescue the phosphor
>from the cruel elements fast enough. How long a period would I have
>coat it? I can just see myself with a hammer in one hand busting
>glass away and spray enamel in the other hehe.
I think it would be like that, tens of seconds I would imagine, don't
truly know though. Nothing to lose if you've got a dead one. Course I
dont know if there would be a reaction with the paint either...
How about fluorescent tubes? Wouldn't need to devac them. Would they
>Here's a question... I once, long long ago, had a big 25" picture
>from a black and white set. Strange thing about this one was that it
>had a matching faceplate of 1/4" glass that came right off. I wonder
>if it defeated some x-ray protection when removed, or if it was
>to protect whomever from the hazards of implosion... Opinions?
Explosion. Old tubes like that are pretty mean. They're fragile, and
when they do break they go off like a shrapnel bomb. Tube safety has
come a long way, thankfully. Those kind of tubes I treat with real
>Last question on the CRT issue... Could one make a haphazard sweep
>generator just enough to make a quarter sized spot in the middle of
>the screen, and then drive the sucker to holy hell and get a weak
I presume so. Your face plate glass would absorb some of them of
course. I don't know just what a CRT could take i and V wise, or the
glass thermally. I expect plenty more V but not i, you'd need to put
some significant neg bias on the grid to control i. That can be done
by grounding the control grid and using a cathode resistor. And I
would take cover in case the glass spot heating caused it to explode
>What might happen if you drove it so hard that it burnt a
>hole in the phosphor... Would it still potentially emit radiation, or
>does the burning destruction also extend to the screen mesh?
The shadwmask is metal sheet, the phosphor is powder on glass, so I
think the shadowmask 'd take a lot more hammering than the phosphor.
>could be done, then it could maybe make a nice tight beam out the
>front end, thus allowing said nutcase to aim it at said seeds and
>from said self. Possible?
The x-rays would come out in all directions. Only the electron beam
would be a beam.
>>> It's all crazy, I know, but know that I do NOT intend to stand
>>> the final device while it runs. I merely plan to run it for the
>>> purposes outlined above via a long extension cord.
>Well... That depends on the power levels produced, if I understand
>propogation correctly. If I am emitting x-rays, do they fall off in
>potency the square of the distance, or am I mistaken?
Indeed, near enough. There's not much absorption of X rays in air.
>Shouldn't I be
>able to create a beam effect using simple aiming techniques, and
>failing that, shouldn't I just be able to operate the device in a
I think the lead box is your only aiming technique. Unless you know
some other you could practically use.
And lead lining and distance will be your only radiation reduction
techniques too. I almost got the feeling from what you just said you
might be considering operating without lead shielding - I am wrong,
How about a trip to the hospital X Ray dept to see how they do things?
> Surely I need not stand four miles away...?
I guess you'd need to measure the rad levels, and stand far enough
away for rad levels to be down to normal: and that might be a long
way. You'd have to be determined, to make it 4 miles, but I really
doubt being in the room with it would give you just background levels
of exposure. But who knows, unless you measure it.
>>What struck me about those articles was the belief that 1/8 inch
>>would stop gamma rays. That is nonsense - point your geiger counter
>>any nuke power plant, they're very radioactive indeed. Last time I
>>pointed a geiger at a reactor it hit the end stop. So if you do this
>>you _will_ be irradiated. And that may not turn out to be such fun.
>>don't try any of it.
>Does this also mean that 1/8" of lead is not a sufficient sheild for
>x-rays, and if so, then how can 1/2" of leaded glass be adequate in a
>CRT? I don't mean this critically, I want to understand this better.
Well, lead glass can be 24% PbO, so say ballpark figure 20% lead. The
xray emission from a TV tube is very low to start with, and the glass
will reduce it to legally accepted levels.
Every so much distance of lead will reduce the xrays by so many
percent: I don't know what the figure is offhand. So any lead will
help things, but to get down to background levels of radiation takes
an awful lot of lead. In practice you're unlikely to be able to encase
your experiement room in a foot of lead, or whatever it takes. So that
leaves you with long distances.
If you're going to do this you need to calculate and measure.
Irradiating yourself by mistake would be somewhat foolish.
A smoke alarm would be a far easier way to mutate seeds. Alpha
particles are of little danger IFF you keep far enough away from the
source, since they are absorbed travelling only short distances. On
the other hand, if you get up close they are much more harmful than
x-rays, as most x-rays pass though you uneventfully, whereas alphas
don't. Alphas are more mutagenic for that reason.
It should be possible to construct a metal chamber to allow you to
slide seeds in and out without exposing yourself to the alphas. Long
as you design corrcetly, no great risk there. Certainly be miles safer
than the sort of stuff you've proposed.
| | * | | With this you could drop seeds in and out
| | without any direct path from alphas to
| | yourself.
|__________| * is the alpha source.
I have to say, dont do any of the above, as there are real risks with
all of it. Unless you really know what youre doing, you could end up