GE-HA3 Helium Argon bulb

[dobie]

Hi Folks,

For years members of the scientific community have been using glow lamps filled with a mixture of helium and argon as sources to calibrate spectral instruments (attached).? The workhorse in this application was the GE HA-3 lamp (there may or may not be a hyphen in the part number), which I assume means "Helium Argon."? There was also a similar NE2 lamp filled with neon.? It was a golfball sizes lamp with mediuym screwbase, and runs directly off of 115 VAC--- which is one of the reasons it is still highly prized.? I spoke to an engineer at GE some 15 years ago, and he claimed all of the archives on this lamp had been destroyed.? I found a display card which indicated they may have originally been intended as low consumption night lights and display lamps.

The "irreplaceable" stockpile we had is dwindling.? The glue holding the base to the envelope has failed on many, resulting in wire damage.? We are faced with buying more, making our own, or attempting repairs.? I'm interested in all feedback.? If you have any info RSVP.? For discussion starters, I see a disk which I assume is some sort of non-ohmic ballast in the lamp base.? Cold resistance on my meter is ~4 kOhms.? Thoughts?? Thanks!

[Tim]

Welcome to the forum dobie,

I have been searching for this lamp for a number of years and finally located one on eBay last year.  I originally thought this was an argon version of the common NE-30.  I was surprised to discover my lamp was marked “HA-3” rather than a typical “AR” designation.  I also believe this is a Helium-Argon filled lamp.  I cannot find the lamp referenced in any my old GE literature, nor referenced in any of the vintage glow lamp manuals that I have.  I would certainly like to learn more about it, such as the years GE made it and for how long.  Your comments about the lamp being used in a spectrograph are interesting.  I did quick Google search and only found one reference to the HA-3, I assume your application is similar:

http://haro.astrossp.unam.mx/Instruments/echelle/echelle.html

I have attached a photo of my lamp lit to help illustrate the color produced to others interested in this subject.  The color is not the same as the AR-1 argon lamp.

Locating more replacement lamps will be difficult.  I have only come across two during the last several years (and I have been actively searching!)  As a last resort, you may want to try (and possibly risk) repairing the lamps with the loose bases.  Other members here can probably give you advice if you decide to go this route.

[pSlawinski]

Hi Tim,

That's a nice lamp you have there!  I have a NE-71 that had a similar problem with the base coming loose.  I was unscrewing it from a lamp and it just came loose!  I sent the lamp to Amelia Samples to see if she could repair it, and I hope to see it again soon!  By the way, is the color of the discharge similar to the AR-1 or does it appear slightly different?

[Tim]

is the color of the discharge similar to the AR-1 or does it appear slightly different?

The color is slightly lighter and has pinkish hue.  The AR-1 glows with a deeper violet color.  If I have time I will try and get a picture of both lit, side-by-side, so you can see the differences.

[pSlawinski]

I have some discharge tubes (similar in look to a neon sign) that contain 5 of the noble gasses.? Helium, Neon, Argon, Krypton, and Xenon (now broken )? I will clean up the pictures, put them on my server, and post links to them here.? I also have some pictures of my AR-1 Lit up on my site.? I tried to match the color as it appears to my eyes as closely as possible.

[pSlawinski]

Helium Discharge Tube:

Large Image: http://www.metal-halide.net/bulbcollectorforumpics/Large/DSC03775.jpg

Neon Discharge Tube:

Large Image: http://www.metal-halide.net/bulbcollectorforumpics/Large/DSC03771.jpg

Argon Discharge Tube:

Large Image: http://www.metal-halide.net/bulbcollectorforumpics/Large/DSC03777.jpg

Krypton Discharge Tube:

Large Image: http://www.metal-halide.net/bulbcollectorforumpics/Large/DSC03769.jpg

Xenon Discharge Tube:

Large Image: http://www.metal-halide.net/bulbcollectorforumpics/Large/DSC02659.jpg

I'm working on a nice enclosure for these.? I have to buy another Xenon sign, and I need to buy a transformer to power all the tubes in series.? When I finish the enclosure I will post pictures of it.

[Alan Franzman]

For years members of the scientific community have been using glow lamps filled with a mixture of helium and argon as sources to calibrate spectral instruments (attached).? The workhorse in this application was the GE HA-3 lamp (there may or may not be a hyphen in the part number), which I assume means "Helium Argon."? There was also a similar NE2 lamp filled with neon.

As another poster mentioned, it's NE-30, not NE-2 (NE-2 is a very common miniature bulb with tubular shape and wire leads.)

It was a golfball sizes lamp with mediuym screwbase, and runs directly off of 115 VAC--- which is one of the reasons it is still highly prized.? I spoke to an engineer at GE some 15 years ago, and he claimed all of the archives on this lamp had been destroyed. [...]

The "irreplaceable" stockpile we had is dwindling.? The glue holding the base to the envelope has failed on many, resulting in wire damage.? We are faced with buying more, making our own, or attempting repairs.? I'm interested in all feedback.? If you have any info RSVP.? For discussion starters, I see a disk which I assume is some sort of non-ohmic ballast in the lamp base.? Cold resistance on my meter is ~4 kOhms.

The ballast is indeed a simple resistor, usually pure carbon composition. Resistance value varies depending on lamp type (and carbon composition is notorious for drifting) but ~4k ohms is reasonable in this case. I have repaired several neon and argon bulbs using this arrangement, including resistor replacement in one case, connection repair in a few cases where the bulbs barely illuminated (the wires were merely twisted together and eventually fell victim to oxidation). If the bulb is only loose in the cement but works properly and the cement is mostly still all there, cyanoacrylate super glue makes an effective repair since these glow bulbs don't normally get hot enough to harm it. More involved repair including soldering of twisted wire connections or resistor replacement is difficult, time-consuming, and risky but I do offer the service at a cost of $50 per bulb. (If I find the bulb beyond repair I'll refund $45, less return postage if you want the bulb back). Reassembly in these cases is done using actual lamp base cement.

[dobie]

Thanks to  everyone for your replies.? Yes, it was indeed an Ne-30 as you pointed out.? My brain got cross-wired while I was typing...Thanks.

Repairing the HA-3 may be an option for some of the bulbs, but I'm also considering "making" some.? There are some drawbacks to the HA-3 as a spectral calibration lamp- namely, very low ultraviolet output due to the glass envelope.? Experimental replacement lamps with UV-transmitting quartz windows worked well enough on the short term, but didn't have the required lifetime since helium passes through quartz.? So basically I have a pretty good "science fair" project on my hands, but not a lot of time.? You understand.

Any thoughts on what the internal gas pressure may be?? Is there a suggested modern resistor replacement (or just a fat old power resistor??)?? Sounds like I need an education in neon sign making or contact with someone who needs anothe project, doesn't it!?

[Alan Franzman]

Is there a suggested modern resistor replacement (or just a fat old power resistor??)?

In a Sylvania Fluorescent Christmas bulb I repaired, the resistor was wirewound on a glass-fiber core, and curled around inside the base. The base came unglued and separated from the envelope, tearing the core apart and unwinding the resistor (though the bulb still worked if I jumpered what had been the direct base-to-bulb connection). Unfortunately I was not able to get or make a suitable replacement core to rewind the resistor, so I ended up substituting 1/4 watt metal film resistors in a series string of 8 to be able to fit in the tiny space. Rather than fitting below the envelope like the original, these resistors fit in a zigzag arrangement like old cage-filament light bulbs, in the recess around the pumping stem of the envelope. Some tricky maneuvering was required to connect this string to the envelope lead, and avoid shorting to the other lead, but it still works just fine.

[James]

Hi Dobie,

The equivalent neon version, NE-30, contains a 4800 ohm resistor in its base.  I would expect the resistor in your lamp to be fairly similar, and see no reason why you couldn't use a standard 1 watt resistor from an electronics retailer.  Modern 1 watt resistors should easily be small enough to fit within a medium screw base.  If not then just use a pair of 0.5W resistors in parallel.

Helium will indeed escape through quartz quite rapidly.  I would suggest that you have your lamps made up in so-called Germicidal glass.  That is a soft glass type with very low iron oxide impurity so that it is able to transmit even shortwave UV-C.  It is made in tube form at Philips Glassworks in Winschoten, Holland and in both tube and S11 bulb shape from Sankyo Denki in Japan.  A number of Chinese firms have also recently begun making this glass type.  It works in just the same way as ordinary lead / soda lime soft glass and seals to them easily.

I am not sure of the gas pressure in the helium argon lamps. Probably it is best found by experimentation.  I would expect it to be in the region 20-50 torr.  You can of course measure it precisely if you have an old worn out lamp you don't mind sacrificing, just break it under water and collect the gas in a measuring cylinder. 

If you need some of the special cap cement for repairing your existing lamps with loose bases just let me know and I would be happy to put some in the mail to you.

Best regards,

James