Hello everyone, I’ve been wondering if such lamps exist. Any information would be greatly appreciated, thanks!

As far as I know, only electronically self-ballasted HPS lamps were made during the early 2000s in China.  Although these were more of an adaptor, into which a standard HPS 35, 50 or 70W lamp could be screwed.

During the 1970s-80s there were efforts at several manufacturers to make a tungsten ballasted HPS lamp and workable designs were conceived and prototyped. However their efficacy and life were not especially impressive, and they were not brought to market.  In the mid 2000s Sylvania picked the idea up again because there was commercial interest in a small self-ballasted HPS reflector lamp for horticultural applications.  I made quite a few prototypes but once again we could not get the efficacy or life high enough to justify pursuing the development.  They had 110W Penning-start arc tubes from SHX lamps, in series with a tungsten ballast filament.  Another of the challenges here was that the HPS arc tube is most efficient in a vacuum outer bulb and the filament requires quite a high pressure gas filling for long life.  Some trials were made with ballast filaments in halogen capsules but even then the performance was not sufficiently impressive.  Nevertheless, maybe it would be interesting if I post a photo of one of those prototypes!

Thanks for the info! Would be pretty cool if they were to hit the market and you definitely should post a photo of one of the prototypes.

I have a old screw in 70w HPS adapter from the 80s, made by Hubbell. It was pretty bulky and would mess up the optics of most luminaries if if would even fit.

Pretty cool! What were their intended purpose?

Never heard of a self-ballasted HPS myself but that sounds like an interesting concept. I’ve seen some of those screw in ballast adapters on eBay before and I’d buy one if I see it again.

I would buy one also but I would use a tin can to make one.