Hi HPS4Ever425120,

I haven't seen any replies to your post, and while I am certainly not an expert on lamp design and construction, I'll share what I've noticed in collecting over the years.
Older HPS lamps (at least GE/Westinghouse) used a large pinch seal tube arrangement for the external amalgam reservoir, while newer lamps seems to have incorporated the amalgam reservoir internally directly into the electrode assembly and isn't really noticeable anymore.
Older HPS lamps also used a metallic strip around each end of the arc tube ends for sealing (I believe it was niobium, which has similar expansion/contraction rates as the alumina).  Newer designs lack these strips, presumably as brazing of the alumina ceramic arc tube with the alumina cap around the electrode assembly was perfected.
I haven't noticed any other noticeable differences between older and newer style lamps, their electrical operating characteristics should be the same regardless of vintage. I have noticed various differences in colour of HPS lamps, ranging from a nice pinkish peach to a yellow-orange, but the lamps were all in luminaires that I could never ascertain the make or model of the bulb due to the diffuser, so I cannot comment on what exactly made the difference.

I hope this helps!

 Anyone know the whereabouts of one ? I wouldn't mind adding one ot the collection . (assuming it doesn't cost an arm and BOTH legs !) 

Yes, possibly. Argon is needed to produce some UV to excite the phosphor.

Some green neon indicators have a visible orange glow under the phosphor. So it still contains neon, maybe mixed with argon or a heavier noble gas.

Ive seen tests of the aliexpress ones with the Seoul Sunlike and they're apparently good but idk if i would actually buy off alixpress to save $5. The guy who bought them for $20 recently tested them but idk how well they hold up. Idk about warranty either.

From what i know, Yuji's Sunwave violet pump are their own thing and may be double pumped. I dont remember. Soraa has their own too. Not sure what Waveform Absolute uses tbh. I think basically everything else violet pumped is Seoul Sunlike.

If i'm not mistaken, the Seoul leds i ordered are the ones used in the Sunsy lamps that are also available on Aliexpress. But we will find that out in one or two weeks time when i get them.

The individual leds are fairly cheap. The strip is expensive but if it is legit, for 120 leds of 2 color temperatures i am not too worried about spending that money. I want strip because of the diffuse lighting i need. The separate leds i can always put into any random ice cream cone LED lamp that costs like 2,50.

I haven't got any violet pumped LEDs myself but if I were going to spend that kind of money on an LED bulb, I would probably buy the Sunsy Shine ones.

But at $25-75 a bulb for quality violet pumped bulbs, I will continue to use real halogens for their even better SPD. Though the 4000K-5700K violet pumped LEDs are quite compelling.

I actually just wrote a super long post on reddit about violet pumped LEDs a couple weeks ago with the same name as here. Idk if linking to reddit is allowed here though.

The main differences between violet and blue pumps is the inclusion of violet(not UV) light which causes fluorescence in a lot more materials, particularly those with optical brightening agents(OBA) so white fabrics and paper will look better. Real incandescents or halogens have enough violet to do this as well. The white rendering differentiates them from even >95 CRI blue pumps which simply dont go far enough into violet to cause fluorescence, making stuff that looks crisp and vivid under incan, halogen or violet pumped LED look comparatively dull.

Their SPD is also fuller and smoother since they use broad spectrum red, green and blue phosphors. No big spikes from a blue pump, no cyan gap and usually a lot of red.

Huh. I've got the later Executive SQR19 variant in NOS condition. Kind of surprised to see the Marquette version.

Hi all,
I have two NOS 250w Sterner Marquette 25 fixtures I need to get rid of. These are 250w HPS 120/240v, and are basically canopy light fixtures with slightly different optics and side mounting instead of top. They measure about 25" x 25" x 12"d, and can fit ED/BT37 lamps. Free local pickup (I'm located in Minneapolis, MN), but I can also ship for an additional fee. I also can include NOS 1980s Westinghouse Ceramalux lamps.

I will likely copy this project at some point but with a lot more neon lamps. maybe arranged in more of a shape that conforms to the globe.... a project that will be a while as I got other stuff I am working on currently.

You'll have to keep heat production into account. The original LED board is aluminium substrate, thermally coupled to the plastic coated aluminium heat sink hidden in the base. That way it can dissipate around 10w, heating up the "plastic" base to around 55 degrees C.
You're best off with a much larger light bulb, i have some CFLs with 15cm decorative sphere on them. Those would be ideal and allow you to easily stuff in 30 neon indicators with no thermal issues at all. But i'm not gonna destoy those. Just patiently waiting until i find something suitable in the recycle bin somewhere.

The neon lamps and resistors can not (easily) be coupled thermally to the heat sink, so at more than say 4 or 5w you'll run into problems keeping everything cool enough. Maybe lamps without the aluminium heat sink exist, so you can drill a bunch of holes in both the plastic base, the bulb, and the PCB to get a convection draft going.

The green and blue "neon" indicators use a different kind of gas. Also easily available. But keep in mind the green ones must be run at well under 1mA to not screw up the phosphor. They're a lot more delicate than the standard ones or the blue ones.