Re: Color Fades in discharges

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: dave pierson <davep@xxxxxxxx>

This, or a very similar, issue was addressed in the early days of
 'neon' lamp (as in advertising) development.  If i recall (I've a
 text around somewhere...)
Issues include:
   fill gas purity
   fill gas (as such: Oxygen is 'bad')
   LARGELY (if i recall) its an electrode issue:  the fields and
   temperatures peak at/near the electrode surface and, over time,
   accelerated (as noted) by current density) the electrode and
   fill gas can react.  Its tricky to get these to be stable over
   time.  electrode materials vary in their stability...

There are advantages to controlled operation to bake out or otherwise
remove contaminants/strays on glass and electrode surfaces....

''air' fill' as such, is likely never to be stable, as the discharge
 drives changes in the gases.

best
dwp