Help! What am I???

Hey guys, it's my first post here and I've got a question (maybe a few, but i'll start with just the one for now)

What is this laser?

I've taken a few pictures of it and there will be more to follow tomorrow when I get a better look at it. All I know is that it's a multiline argon, hasn't been fired up in about a year, supposedly puts out 2 watts and it's air cooled by 3...eh... large normal fans and one, um, really big snail-lookin' fan. It may be ALC, but i didn't see any identification. It's got a honkin' big amphenol umbilical to run to the power supply, and apparently the power supply has a 32A 240V IP-rated blue plug on it.

I've never owned a gas laser, but I've been reading everything i can get my hands on and actually had the opportunity to play with a few. Most of my laser fun-times have been on a q-switched YAG (infinity 2000, w00t)

So, here's the pics, all I could snap in the short time I was with the beast, more to come tomorrow including power supply and (hopefully) internals and diffraction grating image

If there's anything you guys think I should get more details about, lemme know and i'll do my best to find it out, but I'm not sure about the unit's history.

(it's about 3x as long as an ALC60, from what i remember of the one i played with, don't know if that helps)

Thanks very much for your help! More info to follow tomorrow!

WOW... a label.... :thinking:
Oh ya... I know what that is....
Its a Label...

How about showing the whole unit and maybe the insides...

Jerry

All you have shown is the part number for the OPTICS alone. Can't tell you much from that.

Peace,
dave

yeah, i know, it's a bit useless at the moment but there'll be more to come in a few hours

It sounds like a modified HGM. The original has the "snail-lookin' fan" you referred to. The front looks like mine. 2W is probably the upper end of what it can give CW with a lot of extra cooling, but that would explain why the extra three fans were added. I forget the other part#... alc 68x or something maybe?

Hey!
More pics!

The power supply pic is... well, it's crap, but the name on the front is "Continental Laser Corporation" and there's not much more info than that.

The current through the tube is 4A right now as the meter's saying. I'm not sure, but I don't see a power sensor anywhere on the tube. That seems a bit low, as the current owner of the laser said that he used to light smokes on it and it was much brighter. I didn't get a chance to flip that switch to "test voltage" as i'm not quite sure whether it was a good idea to do so, having no documentation for the PSU... am I being paranoid? I also didn't take the PSU out of its rack case to find a current adjustment, and since it's not my laser yet I didn't want to dig too deep and blow something up. Any recommendations on how I should proceed? Is there a higher "safe" current that will let me see how it lases without toasting it? I've heard about 10A being a sort of upper limits for ALC 60's, but this isn't one, so let me know what you think

There's some pics of the inside of the laser, from both ends, as well as the beam. "Beam 1" is the light reflected off the closest thing I could find to a diffraction grating (some wrapping paper, heh, it's that time of year) and you can see the green and blue lines there. "Beam 2" is the light out the back end of the laser... don't really know what the extra dots are? maybe someone can enlighten me... Is that normal? Do the mirrors need walking in? Is that an optics issue or what?

There's some pictures of the insides, not quite sure what i'm seeing to be honest, i'm literally brand new to this as you can probably tell, but i'm very interested in going somewhere with this beast

Thanks very much for your help guys, I know you're all veterans and must get bored of questions like this, but I'm starting to learn already! Trying to plough through sam's faq as much as is relevant, is there any other suggested reading for me? Maybe some documentation on the ALC 68 'cos i'm pretty sure that's an accurate identification... Maybe some documentation on the power supply? I can't seem to find either!

That's a nice looking air cooled argon laser you've got. I haven't seen the insides of any argon lasers larger than the typical ALC60x or Uniphase tube style heads so I can't help you on identifying it

I'm pretty sure it's an ALC68x because of this video...
YouTube - Argonlaser ALC68 Argon Ionen Laser

not 100%, but it looks very similar...

But what about the other issues, such as the low power output, low current on the PSU indicator and multiple weird spots out the back?

Sounds like you're stuck on idle. My Uniphase argon lasers idle at around 3A and only output maybe 5mW when doing so. Isn't there a current adjust knob on the power supply?

Nope, not no the front panel, and the back is enclosed and patched to a socapex and pin and sleeve power connector. There's a switch that says "Anode" on it, but the front of it is broken and the back of it is apparently disconnected, but that's just on the word of the current owner. The power supply draws around 16A @ 240V when it's on, but it has a fat 32 amp plug on it so it must be capable of bigger things.

woot more pics

Like this cake it is a lie.

Not quite what I was picturing, but close. I have a tube that's very similar, but a PSU that's quite different. Yes, it should be capable of bigger things. A watt or more at... 20A maybe? I wouldn't recommend running it at anything less than 7A if you can. I'm going to have to refer you to the folks at PL for further assistance with current adjustment.

It's good to see you're using an insulated screw driver in your pic. Safety is very important when working with high voltage like that. You could get a serious lifter from a power supply like that. Nice laser by the way.
Peace,
Steve

lordoflasers said:

It's good to see you're using an insulated screw driver in your pic. Safety is very important when working with high voltage like that. You could get a serious lifter from a power supply like that. Nice laser by the way.
Peace,
Steve

Click to expand...

Thats a 68B on a MEDITECH power supply. 500-1000 mW cw if the optics are clean and the fans are good. Keep the current to about 15 amps MAX. Make sure you have working fans. They do 3 watts for 15-30 seconds pulsed, in surgical mode and again, around 750 -1000 mW CW at rated current. When pulsed, they need a cool down period between pulses.
ALC was the parent corporation to HGM medical/. Meditech bought their tubes from ALC. They licensed the PSU design from the long gone Continental laser.

Thats a German made surgical power supply. I have the schematics. Meditechs are fragile as power supplies go. They do NOT like to start/stop or run CW at high currents, and make sure the power supply has plenty of air flow. I cant see your cooling arrangements in that picture, but that tube needs about 500-750 CFM when running CW.

4 amps is actually very low, 7 is easier on the tube as a minimum. And I AM the folks at PL who would know I'll be home in a week or two for XMAS and will post back here for you with what you have to hack to get the tube I up. I would NOT run a Meditech much above 15 amps unless you like buying expensive ON Semiconductor power transistors. Dont turn any of the pots on the control cards, just don't. Trust me on that. I know turning up I min seems tempting, but DONT, as the internal controls interact. I do own a Meditech supply. They are now Asculap/Meditech, but they are NOT friendly to hobbyists.

Make sure the fins on the plasma tube are clean, if not, blow them out with compressed air. Dont run it without the top cover, air flows are critical.

Power down the unit and shoot me a pic of the control boards in the power supply so I can try to match up what I have, as your unit has been modified on its rear panel.

your talking late 80s here.


Steve

I stand by everything his man says (as if he needs my approval, lawl).

Steve: Thanks very much for your assistance! Is it a hack to get the tube current up? I saw the control board on the inside has 2 trim pots on it, but i didn't see any silkscreening and i didn't want to poke around in there too much because one of the BIG caps seems to be missing a bleeder resistor (and also my lack of knowledge of WTF this thing even IS!). Also, what's the deal with that internally disabled "anode" switch?!

I totally agree that 4A is a strangely low tube current... If there's no adjustment for it, and it's set automatically, what would cause that?

For a good balance between lifetime and brightness what kind of current would you recommend? It's absolutely the brightest laser I've got access to right now, so is 8A or thereabouts reasonable? Is there a good way of finding the "knee of the curve" or a good balance between current in and power out?

Also, is it possible to clean the optics in this thing without having to realign the mirrors? and is it necessary to realign them anyways with all those weird extra dots coming out the back?

w000t more pics, power supply guts this time Let me know if there's any more useful information you guys need to help diagnose this problem, the laser's packed away now but it's accessible, also... is there a minimum storage temperature for these things?