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ArcticMyst Security by Avery

Tiny HeNe tubes

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CCFL driver might be ok for testing to see if a tube is still gas-intact but I wouldn't run it for any length of time. CCFL inverters output AC and will quickly damage the tube if allowed to run for a significant amount of time.

HeNes need DC and regulated current for best performance and lifetime
 





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Wow those are tiny! And I thought my MG 05-LHP-214 was pretty small :p
 
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I felt this is more relevant here than in the ebay thread: link
Very small tube, and the seller, although ive said before i thought he wasnt legit, is indeed A-OK (I have bought from him).
 
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yeah these are fun tubes too. the 640 is used in laser micrometers (don't ask how I know that)
 
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I received my small HeNe today. It is an MG but the number (00166650)
doesn't search up on Google.
It is 4.5"long and produces the tiniest beam I've ever seen from a HeNe.
Using 125K ballast resistor, I'm giving it 3.4 mA. I haven't LPM'd it yet.
With 100K ballast, I get 4.4 mA which the seller indicates is near max.
I'm not good at pix.... The small dot is at the right edge.
The photo is almost to scale 1:1

9760-henesmall1.jpg


HMike
 
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Yeah, even if I get out of the hobby, I don't think I'll get rid of these. I'd have to be desperate for money to be rid of these. The orange is cool as hell for being so small. I'd also like to note all these tubes are NOS (new old stock) so they're in great shape, though i need to clean the LD one, the anode is getting kinda nasty. nothing a lil methonol shouldn't fix though.

Somehow I skimmed and missed that the middle one was a 612, AWESOME!

Wow, a 6" orange. Probably .1 - .5 mw but still that is incredible.
 
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Yeah my last measurement was .51mW

And mike, I'm not quite sure what that is, looks interesting, though the number on the tube sounds like the serial number.
 
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I thought that was a serial number too.
Still, a nice tube.
I'm looking for a clear plastic tube for a housing.
It will protect the glass and show the plasma!!
HMike
 
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I just leave mine on optical table v-blocks so they remain ventilated. They tend to get pretty hot. It looks like a 001 or a 006, which run at 3.2-3.5mA or so IIRC. I've been running mine 3.8mA or so until I get a proper supply for mine. The bricks they're supposed to run on don't even have alden connectors they're so small...they're smaller than the tube in fact. If I knew its output I could probably tell you which tube it is. We set up a demo tube in an acrylic box once, it was pretty neat. Just definitely want it to be able to breathe. High temps & long run times burn up the tube's life a bit faster, not that red tubes have a shortage of it generally.
 
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I can always cut vent slots in the plastic tube.
I want to protect the mirrors and HV connections.
I don't like shocks !!!!
HMike
 
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I don't like shocks !!!!

Same here. I once got bit by a arc from my 612 when it was on my lab voltex supply, due to one of the connections being crappy unbeknownst to me. it felt like someone belted me in the gut hard. 2400-3400V is what the supply is rated for, at 6.5 mA supposedly. it hurt like hell for around half an hour. Thankfully no lasting injuries, but if testing connections i now use gloves sometimes as an added precaution, it also keeps the tube clean too.

but yeah I definitely would give it room to breathe if you intend to run it in something. My friend and I once had a tube crack from overheating from such a thing. (acrylic box for demonstrations of a 2-brewster tube) it still works, but I frequently have to run it or it gets contaminated. it now has fans on the end of the box to pass air out of the box, passive at the bottom and the fan blowing out through the back top side, so that it minimizes dust, while still cooling it. thankfully the damage was mostly superficial and we were able to seal it with a silicate to keep the tube pressurized. but I always make sure my tubes can breathe now just to be safe. I also note that two smaller ballasts, rather than one large one, tend to be better as well, then they don't get quite as hot.
 
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by the way mike....how is that little tube doing? i'm curious about the output, and the discharge looks a bit pink in that photo.
 
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Ever have a large CRT discharge across your body? That is 30kV as a single jolt. It will definitely wake you up.
 
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One time I took something like 30J @ 1200V to the chest. My arms went flying from muscle contractions
and cut my hand on something. I think I blacked out for a second and then took a big gasp of air. I
checked the voltage on the caps afterward and yep they had completely discharged.
 
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Back when I was an EE student I worked as a video/ audio technician. I had to carry CRTs and a couple of times they were charged between 25kV and 30kV and the hard part was to keep holding it while all that energy discharged through my body. To drop it would have been much worse. Wasn't easy, but I never dropped a single one.
 




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