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ArcticMyst Security by Avery

Finally a GLO (HeNe) :D

Joined
Mar 27, 2013
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So after seeing Daguin's first sales thread many months ago now, I became curious about gas lasers... and after many months of stepping in and backing out, and lots of PM's and communication, I finally pulled the trigger on my very first gas laser. Many thanks to Daguin, 532withenvy, and in particular bloompyle for all of the help :beer:

Now my primary curiosity was the cool plasma effect of a bare tube gas laser. However, fate pulled we away from any gas lasers until now :D

I found this gas laser on eBay: Melles Griot 05 LHP 214 HeNe Laser Power Supply Laser Drive | eBay a Melles Griot sealed laser head, model 05-LHP-214 with a manufacturing date of December 200_. The seller informed me that it was "found" with a power supply next to it, a Laser Drive 106T-1250-4-5 with flying leads. He also informed me that he briefly used a DIY transformer to test the operation of the HeNe, and reported that it flicked to life after 6 minutes. Unfortunately his transformer was only capable of 1A output current, thus his very long power up time. After some research on the all-knowing web and consulting with gas laser fanatic/expert bloompyle, I got a HitLights 12VDC@2A adapter off of Amazon (HitLights 24 Watt LED Power Supply Driver Transformer, 110 volt AC to 12 volt DC Output - Amazon.com) along with the information that this was a 0.5mW 632.8nm HeNe.

Here are the pics of the HeNe by the seller (since the eBay listing will probably expire at some point, is it 90 days after purchase date?):
https://dl.dropboxusercontent.com/u/67636717/Lasers/Melles Griot HeNe/MG 1.JPG
https://dl.dropboxusercontent.com/u/67636717/Lasers/Melles Griot HeNe/MG 2.JPG
https://dl.dropboxusercontent.com/u/67636717/Lasers/Melles Griot HeNe/MG 3.JPG
https://dl.dropboxusercontent.com/u/67636717/Lasers/Melles Griot HeNe/MG 4.JPG
https://dl.dropboxusercontent.com/u/67636717/Lasers/Melles Griot HeNe/MG 5.JPG
https://dl.dropboxusercontent.com/u/67636717/Lasers/Melles Griot HeNe/MG 6.JPG
https://dl.dropboxusercontent.com/u/67636717/Lasers/Melles Griot HeNe/MG 7.JPG
https://dl.dropboxusercontent.com/u/67636717/Lasers/Melles Griot HeNe/MG 8.JPG
https://dl.dropboxusercontent.com/u/67636717/Lasers/Melles Griot HeNe/MG 9.JPG
https://dl.dropboxusercontent.com/u/67636717/Lasers/Melles Griot HeNe/MG 10.JPG
https://dl.dropboxusercontent.com/u/67636717/Lasers/Melles Griot HeNe/MG 11.JPG

So having aquired the adapter ahead of schedule, I went ahead and stripped the head off, which produced a convenient red rubber coated wire and a black rubber coated wire, each made up with a bundle of copper filaments. I suggest anyone needing a PSU adapter to get this, I even found that it has a short circuit check (a loud high-pitched sound is emitted near the wall plug of the adapter). A blue light lights up when the power is connected.

So finally my anticipated HeNe arrived on 9/21, shipped on 9/19. It was packaged nicely in bubble wrap in a small USPS flat rate box. I quickly connected the Alden connectors and twisted the leads of the PSU and my DIY adapter and powered it up. I was greeted with almost instant red light, to my delight :D which quickly turned into concern when the laser flicked out 15 seconds later. Confuzzled, I checked the connections, any loose components in the laser head, nothing turned up. I shorted out the Alden connector with a wire, and then plugged the laser back in. It lit up for another 15 seconds before sputtering out. I made a quick thread asking the forum, in addition to PM'ing Daguin and Bloompyle on the matter. Without any conclusive results, my frustration pushed me over the edge on my curiosity: I decided to take apart the darn tube.

So with much research on the Forum, the first thing I did was peel off the label, to make sure there weren't any screws or glue holes hiding. There weren't any, so two rows of 6 holes each were all the stood in my away, along with the endcaps. So first things first: a sharp pocketknife served as my makeshift screwdriver, and I made a small wedge on each set screw and unscrewed all of the screws, which were alternating on each row (as expected for Melles Griot HeNe's). With that out of the way, I used a small flat head screwdriver to scoop out as much of the glue/silicone/rubber stuff plugged in each hole.

Next was the fun part: how to remove the endcaps. I wanted to preserve everything, so I decided not to boil the endcaps. Instead, I used the old-fashioned method: knife in the cracks, wiggle around. Repeat x times, x=the number of times it takes to get the endcaps to loosen. The front cap actually popped off on my first or second try, much to my surprise. The cap was only a cm or two in the tube, so my knife pried the cap off without overwhelming force. The backside was a different story. Starting with a pocketknife secondary blade, I slowly pried the gap between the aluminum tube and the plastic cap, then used the primary blade of the pocketknife, then used a fruit knife, and finally a large chef knife. By then I was pretty much sawing away on the plastic, but I got a good couple popping sounds, and a couple of firm grasps later, the endcap popped off. This side had at least an inch into the tube, all coated with dried glue. This also exposed the ballast resistors, which were (surprisingly) free-standing with a bit of plastic tubing over it.

So now was fun part, part 2: getting the rest of the silicone/rubber/glue stuff out so I can slide the tube out. I looked through the end of the tube held up to light, which exposed three securing points (where the original glue holes had been). I am not really sure if this was actually silicone, because it was very soft and squishy. A long (5" or so) pocketknife easily dislodged the rubbery stuff, and I actually just loosed the tube out trying to cut away the rubbery stuff. I could use my hands to peel most of the rest of the rubbery stuff off of the tube's glass. Success! :D

So now, this tube uses 2x 35k +/- 5% resistors for ballast, and uses the aluminum casing as a connector from the cable at the back of the tube to a copper strip at the front of the tube. And now was the glorious bare tube HeNe of mine: filled with swaths of orange tape, some writing on the sides, and residue rubbery stuff on the glass :scowl: the tape didn't really seem to have any purpose other than make the neon-orange-pinkish glow look terrible, so all of that was ripped off. Surprisingly, those strips of tape left no leftover stickiness.

Here's the satisfying part: plugging my revamped HeNe back in, it worked brilliantly! 10 minutes passed without a problem, other than the tube and the resistors becoming rather warm. Still not sure why it seems to be working fine now, but I have a nice glow out of my HeNe now :beer:

I forgot to take "during mod" pics, too excited and focused and completely forgot, but here are after pics:
https://dl.dropboxusercontent.com/u/67636717/Lasers/Melles Griot HeNe/IMG_0770.JPG
https://dl.dropboxusercontent.com/u/67636717/Lasers/Melles Griot HeNe/IMG_0776.JPG
https://dl.dropboxusercontent.com/u/67636717/Lasers/Melles Griot HeNe/IMG_0777.JPG

So now I'm a (mostly) happy GLO, a nice little HeNe sitting on my desk :D I have no idea what this post should be, a semi review-tutorial-joyous rant? Anyway, enjoy and thanks for reading, lots of kudos to bloompyle and daguin!

Gotta work on cleaning up the residue and spiffing up my HeNe. Also gotta find a nice little stand for it :D

Oh and +rep to bloompyle and daguin for their help ;)
 
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Joined
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Have to pull that little bit of tape off the glass. I have left mine running over night by mistake so it wont ever overheat. Still stays warmer than a standard light bulb by a long shot. Should design up some acrylic like I did and make a sweet stand.
 
Joined
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Yeah I left that piece of tape on because it's holding down a black strip of something onto the glass, not sure what happens if I remove it. And yeah I need a stand now :p is it bad that the ballast resistors heat up almost as much as the tube?
 
Joined
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You can pull that orange/yellow tape off. It just holds that wire down. Grats on the sweet HeNe!
 
Joined
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My ballast is usually warmer than my tube on my multimode. About the same on my green tube.
 
Joined
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Congratulations on coming to the gas side:beer:! The beam specs are great here
 
Joined
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Yes they are! Although I still have to get used to the 0.1microwatt output coming out the other side :eek: :p
 
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