Nitrogen laser purchase

[Vidal Wolf]

I went to a scrap dealer three days ago after seeing an ad for lasers for sale.
turned out to be a Jodon 50 mw He-Ne, a 200 watt apollo lasers CO2 laser head,and a Laser Photonics model 12 UV nitrogen laser.
I got the Jodon He-Ne and the Nitrogen laser. the Jodon is almost 7 feet long,but is a gas intact, infrared head (bummer).
I opened the hood off the N2 laser and its insides were pretty much spotless,dust free and unexploded. it was manufactured in 1988.
I have nosed around a bit & researched some of how commercial systems perform and operate from online sites.
I borrowed a rotary vane vacuum pump from work, and today filled my LN2 dewar and hopefully ,have pretty much everything I should need to get this going.
its ratings are
150mw average power
and
4 mJ /pulse with a 10ns pulsewidth.
Ive built a nitrogen laser using PVC pipe and glass slides,but it didnt work. go figure! Since its the easiest laser to build, I thought it would for sure work, but no, it failed.. I gave up and built a C02 laser instead that worked.
So Ive got the support components now to run the new n2 laser, I hope it will work come tomorrow.
for tonight,Ive flow purged the head,with the boil off from the liquid nitrogen & brought it down to 10 torr and filled straight nitrogen into the head several times bringing it up to atmospheric pressure each time to give a rough purging of the head.
I dont want any oxygen to be in the actual discharge path when i fire it up for the first time. I dont know the history of the system,and dont know when it was last fired and under what conditions.
I need some advice on startup proceedure. Does anyone have experience with flowing gas nitrogen laser systems?
May I get some advice on a proper or somewhat proper startup proceedure for one of these?
*and now for the pics!*

I want to replace the original power socket with a standard one. then I should be ready to power it on.
again andy advice would be greatly appreciated.
Thanks.
Nate.

[Vidal Wolf]

I failed to get the laser to start because I was unable to get the vacuum pressure down low enough.I could only get it down to 85 torr,and the high pressure cutout switch cuts out at about 50 torr,so I couldnt get it in the proper range.
E for effort
F for *found another way that didnt work*
everything else powers up and goes into standby just fine

[allthatwhichis]

Screw that Nitrogen laser... we couldn't see it even if it worked... Whats up with the Jodon 50 mw He-Ne?

[Vidal Wolf]

Hmmm I gots some *special* UV glasses just for you come over here,and look right into this port looking thing for just a second this wont hurt a bit I promise.

The Jodon is a truely huge behemoth of a monster of a thing.
Its almost as long as an SP 171.
its an Infrared model,the tube lights,and looks *ok*. the dang thing is definitely IR. 3.39um. The Jodon website specs it at 20 mw at the 3.39 line.
I have no idea what Im going to do with it tho. maybe pull the tube and turn it into a huge piece of wall art.I would much rather have the red version of this behemoth. It cannot be repumped for the red line because it is the wide bore model. Altho *if* the tube were repumped with trying to get the 632.8 line lasing, would it actually work? if so how much power theoretically would be realistically possible?

[buffo]

You don't need to re-pump the tube, you just need to change the optics to get red out of that Jodon...

Of course, finding red HeNe optics that have the correct radius for a 7 ft long resonator might prove difficult (!), but apart from that you shouldn't need to do anything else to the tube.

Adam

[mixedgas]

I like a challenge. But this is a long shot. Maybe 1 in 100.

I have a Jodon flat rear optic.
I know who may have a suitable front optic, if he is still alive.
I know where their glassblower works now.

I need to know the distance between the two mirror surfaces in centimeters.

The difference between 3.39 and 633 is adding a few weak permanent magnets for Zeeman splitting to kill the IR lines and the bore is usually etched inside to frost it, if not a bigger in ID. So I'm told. Does it have a prism intracavity like the SP125?
SPs version would run red at reduced power. When your looking at a 100-200 mW red laser, whats a few 10s less mW. Does the plasma light and stay stable?

Get ahold of Sam Goldwasser and Laserman532, we have no idea what they have in their collection.


If it was not huge, I'd expect Eidetic might want it as a collectors item. 3.39 is a useful line if it works.

Steve

[Vidal Wolf]

heres a link to jodon & the specific head. its the HN 50G IR-A

I do not have the power supply yet, I should have that shortly.
I used my line lite co2 power supply to light the tube & a 5 volt DC power supply to heat the cathode filament.
I only ran it long enough to verify its gas intact.

http://www.jodon.com/helium-neon-las...series-lasers/

I am open to the challenge of getting red out of this.
I wish HSC was still around in sacramento I could have gotten a box of magnets that would have done the zeeman split job nicely for about 20 bux.
If I got red out as is, im sure it would be a flashlight multimode beam.

[buffo]

Even without the magnet, you can still get red. You'll undoubtedly get more if you can suppress the IR lines, but with a tube that long, you should be able to get a good deal of red just by swapping the optics.

Take some measurements and then send Steve a PM. He can hook you up!

Adam

[mixedgas]

I was on the phone to Silicon Sam for other reasons, he has a Sp125 RED set, and thinks you'll just go multimode. Multimode 7 foot long hene, hum 100-200 mW. I've seen a repumped 125 do 225 mW. My Oc is 2.5%, so if the radius matches....

First test, look with a grating for hydrogen lines. Then see if you can get a alignment hene or green dpss down the bore and back. If it lases 3.39, that would be nice. I could loan you a detector. If you can do that, go for it!

hum, worth a shot.
No, I did not ask Sam what he wants for the optix.

Steve

[Vidal Wolf]

Ok I just looked at the optics and pulled back the stem guards, the optics are yellowish colored,and clean.
Steve, Im going to look around inside some more, take a few pics & then get ahold of you concerning the feasibility and *sanity* of jumping into this boat. I can see doing a plano/ ? on a short setup, something 6 1/2 feet long? *hmmm* Im intrigued at the thought, I can probably pull it off,but its gonna take some advice =)
I do have the cheat sheet advice you gave me on my 107 He-Ne alignment last year,so I will just refer to that for starters when I swap the optics.
Pictures coming shortly.i have to recharge the camera battery