Re: Micro SSTC + light bulb = plasma globe. Safe( xrays ) ?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Malcolm Watts" <m.j.watts-at-massey.ac.nz> 

On 28 Jul 2004, at 21:12, Tesla list wrote:

 > Original poster: "Hydrogen18" <hydrogen18-at-bellsouth-dot-net>
 >
 > Thanks alot for this info. I guess my flash tubes arent argon like I
 > was thinking. Is the gas inside the bulb below or above atmosphere
 > pressure? I am going to leave this thing running for a while and keep
 > my distance to see if it can actually destroy a bulb.

The gas in most flashtubes I know of is xenon. The initial pressure
is lower than atmosphere (note the length of a voltage rather than
trigger-induced spark compared to one in air at the same voltage) but
rapidly increases to well above atmospheric as the charged cap is
dumped into it in normal use. You will often hear a soft "pop" which
is really a muffled explosion.

Malcolm

 > ---Eric
 > ----- Original Message -----
 > From: "Tesla list" <tesla-at-pupman-dot-com>
 > To: <tesla-at-pupman-dot-com>
 > Sent: Wednesday, July 28, 2004 11:58 AM
 > Subject: Re: Micro SSTC + light bulb = plasma globe. Safe( xrays ) ?
 >
 >
 >  > Original poster: "Jim Lux" <jimlux-at-earthlink-dot-net>
 >  >
 >  > At 07:06 AM 7/28/2004 -0600, you wrote:
 >  > >Original poster: "Hydrogen18" <hydrogen18-at-bellsouth-dot-net>
 >  > >I looked around a little and it seems that if you heat the
 >  enviroment and > >emit HV at the same time(I'm definetly doing this)
 >  as well as provide > >another plate for the electrons to hit you make
 >  x rays. Since I do not
 > have
 >  > >the receiving plate it eases my mind some, as do your comments on
 > puncturing
 >  > >a bulb. Thanks. Btw, can someone explain why the plasma is more
 >  intense
 > in a
 >  > >vacuum with HF HVAC than in free air(it is a better conductor)? >
 >  > > >---Eric > > X-rays are unlikely except in a vacuum.  HV and
 >  Vacuum is the combination > that raises the x-ray hazard.  No, you
 >  don't need a plate for the
 > electrons
 >  > to hit... anything they hit causes them to slow down, which is what
 >  causes > the radiation (called bremsstrahlung.. braking radiation in
 >  German), just > metal works real well, and can conduct away the heat
 >  that results (most of > the energy goes into heat, and a very little
 >  bit goes into the Xrays. > > Large CRTs are heavy, in part, because
 >  the faceplate is loaded with lead > oxide (for strength and
 >  shielding) > > Lightbulbs (except very low wattage, 25W) are filled
 >  with argon or > nitrogen, typically (it keeps the tungsten on the
 >  filament from
 > evaporating
 >  > as quickly), and, so don't present much of a radiation hazard (i'd
 >  worry > more about breaking and imploding or exploding) > > Plasma is
 >  more intense at low pressures because it's easier to ionize the > gas
 >  and keep it ionized.  In a dense gas, the ionized, energetic atoms
 > tend
 >  > to hit other cold atoms and lose their energy.
 >  >
 >  >
 >
 >
 >