omni 543-200MA - quest for another Argon (was which exciter)

[ultimatekaiser]

Interesting! I wonder why mine doesn’t have one then. Though I do tend to see them on the 543s a lot more than on the 643s. How odd. I should put the YB optics back into mine and see what I get out. I don’t think I’ve put that one back in since I first fired it up. I fixed it with the RYB optics. Probably get a lot more of the blues and more 568 out by killing the reds.

 

[vk2fro]

Coupla pics for ya:

This shows the big hazmat stickers - theres a second one to the left. No doubts on it containing dangerous material!

And heres the hours meter. What a waste

edit: holy crap - thats a 33 hr tube - almost brand new. Even worse!

 

[ultimatekaiser]

Yeah that’s terrible.

 

[vk2fro]

Exactly - would have been a steal at the $150 I paid for it. Like brand new.

 

[ultimatekaiser]

Yeah. It’s a real shame that gas is finally dying out. There’s something very elegant and imposing about the glowing gas. Smallest Argon ion I have ever seen was about the size of a Coke can. It was about the power of a laser pointer, and used for a microscopy and scanning. It was a cute lil thing.

 

[vk2fro]

Wonder what the voltage drop across its tube was?

I'm going to try experimenting with the omnichrome optics with the ILT - could be interesting.

 

[ultimatekaiser]

Probably not worth it. Although you could do it three mirror resonator with care if you ran it constant current. Don’t do it with the light feedback/power control on. you’d confuse the snot out of the power supply and make it behave erratically.

 

[vk2fro]

That was the plan - 3 mirror res - probably won't do anything tho. And yes current mode - the photodetector would otherwise send erroneous data to the psu

 

[ultimatekaiser]

Yeah I’m not 100% sure how the ILT would handle that. Most ions have it running all the time regardless, for noise canceling, in order to prevent the arc plasma from oscillating or wandering.

 

[vk2fro]

oh well I have plenty of other optics to play with - a diffraction grating (also known as a CD ), some dichros and a polygon scanner out of a laser printer. Oh and a set of DT40 W's

 

[ultimatekaiser]

Fun stuff! The three mirrors thing can be a lot of fun if done well. Sometimes I can give you extra lines that you wouldn’t normally get and things. If you have a good stable Mirror mount and surface it’s worth a try.

I have a big collection of mirrors. Can be fun seeing what they all do.

 

[vk2fro]

yeah playing with optics is quite a treat, especially with gas lasers.

Just scored a supply for the ILT - if the ILT from ebay ends up dead, at least I'll have a spare to go with my other ILT

Trying to motivate myself to strip down the omni - I finding it difficult to tear down such a mint condition (but as we know broken) laser.

Whats got me beat is, why didnt omni use a stainless steel gas ballast like in the coherent novus surgical lasers - those things are built tough.

 

[ultimatekaiser]

yeah playing with optics is quite a treat, especially with gas lasers.

Just scored a supply for the ILT - if the ILT from ebay ends up dead, at least I'll have a spare to go with my other ILT

Trying to motivate myself to strip down the omni - I finding it difficult to tear down such a mint condition (but as we know broken) laser.

Whats got me beat is, why didnt omni use a stainless steel gas ballast like in the coherent novus surgical lasers - those things are built tough.

Those lasers (at least the one I saw, were pretty small and didn't have a ballast. they do have metal fixings on them, but they're for the water cooling. Only a few very large Ions had gas reservoirs on them. and the omni's are the only ones that have a gas ballast. the tubing is not spare gas, as far as i'm aware, it is simply to help the gas circulate properly, as the gas returns are too small for Krypton usage, and don't serve much purpose in the Argon version. (Kr has a higher flow rate and eventually it goes dim at higher currents as all the gas gets trapped at the opposing side of the tube if the return is too small) and so it just acts as a buffer to make sure there's enough gas present, until the other end flushes far enough to catch up. They likely just use the same tube for cost reasons...as well as using glass as it's probably cheaper due to the shape they chose. Larger tubes had chambers that actually added gas to the tube after hundreds of hours because the pressure would drop too far after a while, much like HeCd lasers, and had a command on the controller to cycle those valves and add gas to keep the pressure correct. the small ones in the novus don't have that to my knowledge. There's just a white tube, and a large black igniter that runs alongside it if my memory serves.

 

[vk2fro]

Just ordered some imperial hex drivers so I don't have to sit around in final cut chopping out video while I try in vain to use metric tools on imperial fasteners

I watched a teardown of a novus 2.5w surgical - he couldn't get the laser in it to run so he ripped into the tube (but was careful with the BeO). Hearing the "wooosh" as the tube went up to air when he removed the OC was a bit disconcerting... The gas ballast was covered in black shrink tubing and had 4 refill ampules on the end when the tube pressure got low.

 

[ultimatekaiser]

Its been a while since I’ve seen anything other than air cooled one. I believe you.

But they’re not a ballast though. They’re gas reserves. They are the reason ions have to be run continuously otherwise they will go high pressure. The one on the omni is a ballast if I remember correctly-not additional gas. I dont think its a true gas reservoir. But I could be wrong. I haven’t taken one of these apart in ages. I do remember that the screws that held the cover on were an unusual size though.

 

[vk2fro]

Well mail man just delivered a set of imperial drivers so now taking apart the omni should be rather simple. About time I bought a set too - this being the second time I've needed a set of imperial drivers and had to make do with a metric set or borrow them from a friend.

The ILT is paid for and should be in the mail sometime later (due to the time difference, it'll probably go in to the mail this evening when its day time over in the united states.

The seller has followed my instructions for double boxing and using squishy foam around the outer box, so hopefully this laser will arrive in tact!

It appears to have a nice adjustable base plate on it too, and it does have the remote cooling option but I'll re-wire it for local fans. I'll take one from the omni for the top fan, and grab a couple of papst units I have which are identical to the ones that are on my other ILT, each is 108 CFM, and the top one god knows what, but they're monsters when they spool up.