[Milsurplus] Lamp 991 re-fire

[John Hutchins]

Bruce -

Thanks for the explanation.  This explains my observation. The lamp now 
fires at ~100V and regulates around 72V after firing.
Thanks
Hutch

>   The neon will not condense or solidify unless cooled hundreds of
> degrees below zero. There are two likely reasons for the lamp behaving
> this way, and the remedy is to get it lit until it heats up for a while.
> First, the neon may enter the crystalline structure of the electrodes.
> It does not combine chemically because it is an inert gas.  Heat will
> drive it out and restore the gas pressure to the correct level. Second,
> the opposite effect will happen with other stray gasses interfering
> with  the operation of the lamp.  These gasses may enter through tiny
> imperfections in the glass and foul the neon. Once the lamp lights and
> heats up, these will combine chemically with the electrodes and be held
> there.  Neon signs undergo these effects over time if they are idle or
> leaky. Stray gasses eventually combine with the electrodes and interfere
> with contact to the inert gas. Because the sign tubing is too expensive
> to discard, the ends are cut off and ones with new electrodes are
> welded  to the tube, which is then  evacuated  and refilled. Does anyone
> remember the now rare "flicker flame" bulbs for decorative lighting?
> They used chosen electrode materials and gas pressure to give the effect.
>
>        Bruce Gentry
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