Playing with Neon's

I took delivery of some neon globes today with my 12V to 2000V power supply

EDIT: by the way all these photos were taken in a brightly lit room. These things are SO bright that the camera had to close the aperature so much and all you can see is red-orange. They surprised me how bright they were, I was thinking of dim neon signs, these are WAY brighter than that!

Here are the neon's. The ones with three turns are 1958 vintage and the six turn one is 1962. The small one is a regular neon indicator bulb:



Photoo's of them lit:







As you can see, you don't have to even touch the power supply to ionize the neon:



And I could get 1/4" of arc from the little power supply too. If i get excited I may make a 12kV diode ladder for it:




Anyway, just thought I would share... Next, Argon, Helium, Hydrogen and Sodium!

Funky tubes!

Indeed neon is fairly bright. I think most of the time with signs they intentionally limit the brightness a bit, so they are easier to look at.

Yeah, neon signs have got funny ratings. A "10kV" power supply may actually be 2kV RMS. They mix gasses in them to alter the colour too, most "neon" signs aren't pure neon. They can often be mercury and neon filled with phosphors for colour. Also, the bigger diameter the tube the dimmer it is. Small 1-2mm capillary tubes are REALLY bright. Neon signs are usually 8-15mm.

Mercury isn't mixed with neon. It's either neon, or mercury/argon. Unless it's a clear tube and exactly that color, it's most likely a fluorescent lamp instead.

AUS said:

Yeah, neon signs have got funny ratings. A "10kV" power supply may actually be 2kV RMS. They mix gasses in them to alter the colour too, most "neon" signs aren't pure neon. They can often be mercury and neon filled with phosphors for colour. Also, the bigger diameter the tube the dimmer it is. Small 1-2mm capillary tubes are REALLY bright. Neon signs are usually 8-15mm.

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Now, is that an effect of incident light intensity since light is being sourced from a smaller point? And a wider tube doesn't have the same flux density? Or is it something else??

@cypyaragon, thanks for the correction, mercury & argon not neon. I think as you say the majority of tubes these days are flouro's with a phosphor in the tube.

@meatball, I have no idea of the therory I'm just starting to explore gas discharge tubes.

AUS said:

Yeah, neon signs have got funny ratings. A "10kV" power supply may actually be 2kV RMS. They mix gasses in them to alter the colour too, most "neon" signs aren't pure neon. They can often be mercury and neon filled with phosphors for colour. Also, the bigger diameter the tube the dimmer it is. Small 1-2mm capillary tubes are REALLY bright. Neon signs are usually 8-15mm.

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***Depends on what kind of NST we are talking about.
Solid state vs old style NSTs. Old style NSTs output under normal conditions, higher than rated output. 12Kv easily do 17Kv at 65mA.

AUS said:

...tubes these days are flouro's with a phosphor in the tube.

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You're repeating yourself. That's what fluorescents are. Without a phosphor it's not a fluorescent lamp, it's just a discharge lamp or glow lamp.

Cyparagon said:

You're repeating yourself. That's what fluorescents are. Without a phosphor it's not a fluorescent lamp, it's just a discharge lamp or glow lamp.

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Yes you are correct of course.