Re: X-rays from light bulbs/Tesla Coils !!!

Many modern light bulbs do not have a high vacuum, but instead
a medium vacuum and a small amount of gas such as argon.

If you can see corona coming off of the filament inside the
bulb, then you have a bulb with gas. These are quite safe
and produce no measureable x-rays.

Almost ALL older light bulbs were made with a HIGH vaccum,
which explains Jeff's "antique bulb" giving off x-rays.

Some of the smaller SIZE lighbulbs still use a high vacuum.
Just last year I was producing x-rays with a 30 watt bulb.
It is easy to distinguish when a bulb has a high vacuum.
When you attach them to a source of HV they fluoresce
green, blue, or white along the walls of the tube. If you
see corona inside the tube, then there is no fluoresence
and no x-rays.

Things that I personally KNOW give off x-rays:
X-RAY tubes
Crookes tubes (and other types as found in science labs)
SOME Geissler tubes (walls fluoresce)
Older style light bulbs (almost all)
New light bulbs of small size/wattage (Large ones don't)
Radio tubes (Not all, but about 50% of the types *do*)
Cathode ray tubes / Oscilloscope tubes / TV screen /
Computer monitor screen

ANY higly evacuated vessel is a candidate for x-ray

Dewar flasks
Thermos bottles

Bottom line: if it fluoresces, it most likely can produce
x-rays. The exception to this rule is the fluorescent
light bulb. These contain mercury vapor that when excited
gives off UV light that in turn excites the fluorescent
material coating the tube. They do not produce x-rays.

If a light bulb is being run on a Tesla Coil such that 
the filament is giving off incandescent light, this is OK.
No x-rays. If the filament has corona coming off of it,
this, too, is OK. No x-rays. If you see the GLASS walls
fluorescing, the danger of x-rays is quite real.

Hope this helps.
Fr. Tom McGahee

> From: Tesla List <tesla-at-pupman-dot-com>
> To: tesla-at-pupman-dot-com
> Subject: X-rays from light bulbs/Tesla Coils !!!
> Date: Monday, September 06, 1999 12:33 PM
> Original Poster: "Jeff W. Parisse" <jparisse-at-teslacoil-dot-com> 
> John, Jeff, Group...
> Wait a minute! Let's back up. Maybe I missed something.
> X-rays from a TC excited light bulb? I use a VTTC to light lightbulbs
> and/or create corona on the filaments all the time as I'm sure
> many of us with VTTCs do.
> Are there any x-ray experts willing to comment on the thread below?
> Jeff Parisse
> > >Just wanted to relate that I have produced x-rays using an antique light
> > >bulb and a small 3-4" spark Tesla coil.  The radiation was strong enough
> to
> > >weakly fluoresce an x-ray screen with a target shadow (paper clip used
> for
> > >target object) between the bulb and screen.
> >
> > THANK you for this email.  When I started out fiddling around with Violet
> > Rays and different smaller Tesla Coils, knowing nothing anything about
> > Tesla, sparks, or radiation I was lighting up Edison bulbs and noting that
> > the glass phosphoresced a beautiful yellow green colour, and that the
> > filaments and posts inside cast black shadows on the glass.  Didn't have a
> > clue what was going on.  I must have played quite a long time with this
> > light bulb, and in the weeks time acquired a half dozen or so more bulbs
> to
> > play with, and found similar results.