Re: 40w globe lightbulb = safe plasma ball?

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

Original poster: "Malcolm Watts by way of Terry Fritz <twftesla-at-qwest-dot-net>" <m.j.watts-at-massey.ac.nz>

Hi Dave,

On 9 Oct 2002, at 17:24, Tesla list wrote:

> Original poster: "davep by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<davep-at-quik-dot-com>
> 
> > I looked in the Pupman archives and found this thread. 
>  
> > It seems that if there is sufficient gas in the vessel
> 
> > to create streamers/corona then the evacuation is
> 
> > insufficient to create hard radiation.
> > But if the walls fluoresce, X-Rays may be being produced.
> 
> > Perhaps there is a threshold torr that may allow both
> 
> > situations to occur.  
> 
> 
> 	A curious factoid has floated up in my brain,
> 	from the vacuum tube days.  In the manufacturing
> 	process, after the vacuum was pulled, and the tube
> 	sealed, a 'high' voltage (unknown, presumably tube
> 	specific) was applied between 'something' and
> 	'something else': this 'pulled' stray atoms,
> 	left behind by the vacuum pump, and strays
> 	absorbed on the elements, glass, etc, out of
> 	there and slammed them into the walls, typically
> 	leaving a silvery spot.  This was called
> 	'gettering'.  IIR, one of the normal electrodes had
> 	an additional electrode called a 'getter', of
> 	no function in normal operation (being out of the
> 	electron path) but useful here.

As far as I'm aware, the getter is actually sputtered onto the glass 
from a pad by heating the pad with an induction heater.

     I experienced a minor drama earlier this year when I was 
delivered a consignment of tubes with the getter pads loaded but not 
actually fired. I finally managed to get the company involved to 
replace them with tubes having, in their words, "traditional getters".
Admitting to QC errors was obviously not in the company manifesto.

Regards,
Malcolm

  
> 	The relevance:
> 	I _speculate_ that similar MAY happen in a lightbulb,
> 	under Tesla excitation: _improving_ the vacuum over
> 	time.
> 
> 	Independently, my guess is that which bulbs have vacuum,
> 	which have inert backfill varies from manufacturer to
> 	manufacturer and from size to size...
> 
> 	IF my speculation is correct (IF), I would doubt that a
> 	backfilled bulb could be 'cleaned up', however one with
> 	a 'dirty vacuum' might be 'improved' enough to change
> 	its performance as a (potential) x-ray source.
> 
> 	best
> 	dwp
> 
> ...the net of a million lies...
> 	Vernor Vinge
> There are Many Web Sites which Say Many Things.
> 	-me
> 
> 
> 
>