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ArcticMyst Security by Avery

Spectra Physics 155 HeNe

Joined
Mar 10, 2013
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That's not an easy question to answer because every tube is kind of unique. The tubes were made to be put into service and run continuously. Honestly if it's lasted this long. Its not gonna leak again on a timescale that matters. The loss of helium will make it much harder for the tube to start and run, and will cost it some power. A few hours a month is probably more than adequate. Sam has her old one 19 that actually has to be run pretty much weekly, or it turns pink but it routinely clears up.

Look at the back part of the cathode and find the little ring. Directly above that there should be a thick black spot of barium getter on the glass. If that has turned white in places that means that it has taken on contamination overtime. If there is no spot then it probably was never fired. A lot of later tubes didn't always get a proper getter activation. My 156 has faint whisps of white, so i can tell it was attempted, but didnt reach flash temperature so only a very little bit of the barium vaporized. And that it has leaked, but minimally.

I have a 124 that works that i revived, if you want one but it wouldnt be cheap. I slightly overfilled it to help it last, but since its He4, the power isnt quite fully up to spec, since its not as efficient as the lighter isotope He3, which is generally what is used-though it is far more expensive.
 





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Those old laser tubes are beautiful hand done works of glass art.

Fantastic pictures Diachi
 
Joined
Mar 10, 2013
Messages
2,918
Points
113
Those old laser tubes are beautiful hand done works of glass art.

Fantastic pictures Diachi

indeed. though if you think that's true, you should see the bare glasswork of a HeCd/HeSe. they're far more complex.
 
Last edited:
Joined
Jan 2, 2008
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You know I realized I got mixed up on this :( stupid me - Sorry for my confusion.

I was thinking 125 not 124 - the big 6 foot behemoth.
Not the thin 124

Both are softseal - I have a 127 and sometimes the numbering on these gets me confused.

My 127 runs and is stable at about 40mw. So other than size and hassle I haven't seen a reason for a softseal. The 155's are cute for the size and tempting. :)

The 125 is the grand-daddy I was thinking of.

Ever seen one of those running? Are any of them still operational?

That's not an easy question to answer because every tube is kind of unique. The tubes were made to be put into service and run continuously. Honestly if it's lasted this long. Its not gonna leak again on a timescale that matters. The loss of helium will make it much harder for the tube to start and run, and will cost it some power. A few hours a month is probably more than adequate. Sam has her old one 19 that actually has to be run pretty much weekly, or it turns pink but it routinely clears up.

Look at the back part of the cathode and find the little ring. Directly above that there should be a thick black spot of barium getter on the glass. If that has turned white in places that means that it has taken on contamination overtime. If there is no spot then it probably was never fired. A lot of later tubes didn't always get a proper getter activation. My 156 has faint whisps of white, so i can tell it was attempted, but didnt reach flash temperature so only a very little bit of the barium vaporized. And that it has leaked, but minimally.

I have a 124 that works that i revived, if you want one but it wouldnt be cheap. I slightly overfilled it to help it last, but since its He4, the power isnt quite fully up to spec, since its not as efficient as the lighter isotope He3, which is generally what is used-though it is far more expensive.
 
Joined
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Messages
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Points
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Yeah a few of them. There are still some places that refill them too. I don't have one because I don't have a place to put one they weigh about 100 pounds. I used to clean and maintain one though. There's a couple of different variations of it. Huge hene. Odds are any that you run across will not be working. There's been a number of times I've seen them pop up on eBay for a few hundred dollars and can be refilled for a couple grand. Great research laser, but the 127 is generally considered superior overall except in power.

The power supplies are what are hard to find
 
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