Argon question

[Anthony P]

Recently I ordered a 2214-40MLA argon head on e-bay. It has not shipped yet, but I received a message from the seller about starting issues. I know argons have to be "exercised" periodically. A good warm up may rejuvenate it. What do you guys think? Here is the message I received:


Thak you in advance for your input.

 

[mojo_1234]

Had the same issue with my old Lasos LGK 7872. Was sitting for around two years and had serious issues during ignition. But after 10 or so "ticks" the laser has started. After running it for a couple of hours around 80% the issue issue got solved until today. Recommend SAMs Laser FAQ for further reading.

 

[kecked]

It’s getting near end of life. I’d pass.

 

[diachi]

It’s getting near end of life. I’d pass.

Might be a combination of age and sitting unused for a long time. eBay listings can sometimes be up for quite a while so who knows when they last fired it up.

Those heads have an hour meter on them, having the seller check that would be a good idea. Would give at least some indication of what state the tube is in, anything above about 5,000 hours is getting old, especially if the tube has been run hard for that time. Power output and number of lines would also be a good indication.

Hope they didn't let it sit and *tick tick tick* for 10 minutes. That's not good for them. Best to turn on power, which turns on the filament and then let it heat for a few minutes then try to start it. Then once it's going give it a good long run, depending on what state it's in that could be a few hours or it could be a couple days.

 

[Anthony P]

Can you tell me, where is the hour meter on these heads. I own a 2214-20 SL and now I am more than curious, but a little intimidated by taking screws out of it to look.

Edit:
I did some checking around and found a picture of this style tube with an hour meter on it outside of the junction box... neither my 20SL nor the 40ML I am considering have this feature.

 

[Mosc007]

The Hour Meter is on the PCB underneath the output end. A few screws and the cover can be safely removed. It's the PCB that has the Photo Diode for measuring output. They can be very hard to read sometimes. A Good magnifying glass will help. They are a chemical hour meter. A little bar changes color from 0 to 10,000 hours.

I bought quite a few on Ebay before I got one that worked.

 

[Anthony P]

The Hour Meter is on the PCB underneath the output end. A few screws and the cover can be safely removed. It's the PCB that has the Photo Diode for measuring output. They can be very hard to read sometimes. A Good magnifying glass will help. They are a chemical hour meter. A little bar changes color from 0 to 10,000 hours.

I bought quite a few on Ebay before I got one that worked.

OK, I have the board out... still do not see meter or indicator of any sort. There is, however, a smaller second pc board attached perpendicular to the photo-diode board. The back reads "UPC Hour Meter Card BL/AL rev c, National Laser Co 07030HEAD, 29 Aug 2003, KJW"
The front of the board has a largish black box labeled " Curtis Instruments, inc. 201PCN 5VDC 08150C". There is an open 3 prong connector labeled In,GD,BO. If I recall, this head was rebuilt professionally at some point.
I suspect it some sort of access port to connect an external reader. Any thoughts?

 

[icecruncher]

Usually those heads are pretty bullet proof - at least in my experience.
Although certain heads can also be over sensitive to drafts/cold and either not want to come on, or wink out while running.

 

[diachi]

OK, I have the board out... still do not see meter or indicator of any sort. There is, however, a smaller second pc board attached perpendicular to the photo-diode board. The back reads "UPC Hour Meter Card BL/AL rev c, National Laser Co 07030HEAD, 29 Aug 2003, KJW"
The front of the board has a largish black box labeled " Curtis Instruments, inc. 201PCN 5VDC 08150C". There is an open 3 prong connector labeled In,GD,BO. If I recall, this head was rebuilt professionally at some point.
I suspect it some sort of access port to connect an external reader. Any thoughts?

Sorry I never got back to you sooner, got any pictures? Should just have a regular old hour meter in there. Some I think may have had a numeric readout but all the ones I recall in those heads had the bar readout.

 

[Anthony P]

Sorry I never got back to you sooner, got any pictures? Should just have a regular old hour meter in there. Some I think may have had a numeric readout but all the ones I recall in those heads had the bar readout.

https://imgur.com/ftS61Z9

https://imgur.com/l31DC6N

https://imgur.com/fZ985bl

 

[diachi]

https://imgur.com/fZ985bl

Huh, hadn't seen one of those before on those heads.

Found a datasheet. Looks like it's just RS232 data out, would guess that 3 pin connector is your serial interface. Can't find much more than that unfortunately.

 

[Anthony P]

I may contact National Laser Co. to see if it is possible to read it from home. I will let everyone know what they say.

The "new" 2214-40MLA arrived today. It fired right up for me and ran steady with no issues. Diffraction grating shows 7 distinct lines, maybe a dim 8th between blue and violet? Power meter reads 60+ mW at 8A. I am using Sperr 840011. It has always proven dead on for red lasers, but I question its accuracy on other colors... even with the color correction chart.

The 40MLA has the bar type hour meter in it that looks like a tiny, old-fashion thermometer. I haven't been able to read it yet even with mag glass. Does the laser have to be on to read this type of meter?

 

[diachi]

I may contact National Laser Co. to see if it is possible to read it from home. I will let everyone know what they say.

The "new" 2214-40MLA arrived today. It fired right up for me and ran steady with no issues. Diffraction grating shows 7 distinct lines, maybe a dim 8th between blue and violet? Power meter reads 60+ mW at 8A. I am using Sperr 840011. It has always proven dead on for red lasers, but I question its accuracy on other colors... even with the color correction chart.

The 40MLA has the bar type hour meter in it that looks like a tiny, old-fashion thermometer. I haven't been able to read it yet even with mag glass. Does the laser have to be on to read this type of meter?

No reason you shouldn't be able to read it from home, it's just standard RS232 from what I can tell. No idea on baud rate or anything mind you. Sure Curtis Instruments would help you out if you reached out to them.

7 (maybe 8) lines at 8A is good. Multiple lines tend to skew readings with optical LPMs but if that's anywhere near accurate then that's good power at 8A.

Those bar style hour meters do not need to be on to be readable. Perhaps just very low hours? Though they can be hard to read.

 

[hakzaw1]

lots of great advice from all.
active cooling requirement.
The fan needs to pull air thru the laser==NOT 'blown' IN.
If the laser gets too hot to touch ,,,, your cooling may need to be improved.
IF the laser 'shuts down' -- stop doing that-- MOST times, after cooling down the argon will work as before...
but I hate the 'wait'--
ALSO it is not uncommon for a well used argons to take a while to 'fire-up'

 

[diachi]

If the laser gets too hot to touch ,,,, your cooling may need to be improved.
IF the laser 'shuts down' -- stop doing that-- MOST times, after cooling down the argon will work as before...

Yup, there's a thermal cutoff switch attached to the tube that's part of the interlock loop. You'll usually hear it click off and the interlock OK light will turn off if it heats up too much. Best not to do that too often.

Good advice with the airflow too, needs to pull through not push. Never did like the 2214s for cooling, cooling is easier on the 2211s (square heads).

 

[Lasertekk]

Pressure. Parked ion lasers will drift up in pressure. Mostly from gas buried in the bore slowly outgassing or a leaking fill system, if so equipped. A cathode reactivation will at times both bury the excess gas ( placing the pressure within a more comfortable region where the starter can now do its job) and increase the cathode's emissivity. My experience is confined to 5 watt to 30 watts systems. I have almost no experience with air cooled.