Hello im just wondering if there's a possible way of prolonging the pink glow you get on the startup of some sodium bulbs.

Thanks dd

Underdriving the lamps would be easier on a HF ballast (from some CFL,...), e.g. a 9..15W ballast feeding a 35W SOX...
You just short circuit where was the tube filament and each of them connect to the SOX lamp.
But after this treatment, never ever try to turn ON the ballast without the lamp, it will blow within seconds...

In any case the lamp will not survive intact: Either the vacuum loss, or the electrode wear from underdriving.

Ok thanks guys for reply. Seems a little more hassle than its worth...maybe a cathode tube instead.
dd

Take it to a neon shop and get them to fit it with a plain argon tube.

Luminarie will a cathode tube give me more or less the same effect as a argon tube?

Thanks dd

Luminarie will a cathode tube give me more or less the same effect as a argon tube?

Thanks dd

What do you exactly mean by the "cathode tube"?
Each discharge has all the time one cathode and one anode, eventually swapping over when the current polarity changes...
Or no cathode/anode at all, if it is an induction discharge...

http://www.ebay.com/itm/Set-of-noble-gases-in-ampoules-Helium-Neon-Argon-Krypton-Xenon-discharge-lamps-/171192525325

I searched the web and that's what I came up with. Expensive, but I wouldn't mind having a set.