Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

How to Register on LPF | LPF Donations

New toy

J

james1095

0
Joined
Jun 24, 2010
Messages
243
Points
18
Just received the Melles Griot 05-LGP-173 that I picked up for 10 bucks on ebay. I just happened to recognize the model number as a 543nm green head. It was as-is and when it arrived it made an arcing sound and glowed but no beam. Popped off the end cap and replaced the insulation where the ballast resistor had arced to the housing. I could see that the discharge color of the tube looked normal so I put a little pressure on the mirror mount (with a plastic stick!) and got a flash of green light. 40 minutes of twiddling with the alignment screws until pressure in any direction would reduce the output and I've got a nice green HeNe. I've wanted one of these for ~20 years but they were always too expensive. With a min spec rating of 0.3mW it's sure not gonna burn any holes but there's something about a glowing glass plasma tube that gives gas lasers some great appeal to me.
 





Should take a picture of that puppy all fired up.

Green hene's are fairly hard to come by, as are yellows.

But if REALLY want to see a lit up plasma tube, try and find an argon (the one with the glass looking tube, not ceramic). They also have a pretty awesome plasma discharge :)
 
Ten bucks for a green HeNe? I am green with envy! LOL
That's a heck of a cool new toy. How long is the tube? What are you powering it with?
- Robert
 
Oops, I thought I'd attached a pic but apparently it was too big, trying this again.

The tube is about 16" long, I can measure it later but the specs can be found on the MG site. I'm powering it from a standard HeNe brick outputting 6.5mA, it needs about 2600V according to the spec but I've not actually measured this one yet.

I have a yellow one that I got several years ago, it cost me quite a bit more than 10 bucks though! I have one argon laser too, but it's a Cyonics with a ceramic plasma tube. When I can tolerate that roaring fan it makes a good space heater :)
 

Attachments

  • 05-LGP-173 lowres.jpg
    05-LGP-173 lowres.jpg
    105.6 KB · Views: 207
hehe yep my argon sounds like a 747 winding up for takeoff when that big fan fires up. And they do make a good heater - I was actually using mine *AS* a heater when my regular source of warm went to electrics heaven. Mine is all enclosed, so even if it had a glass tube i wouldnt be able to see the discharge.
 
Here's another pic, looking into the OC prior to aligning the mirror. There's no laser output here, just the plasma discharge and the violet bore glow. The brewster plate (polarized tube) is clearly visible mounted behind the mirror. Also worth noting is that the output is from the anode end of this tube which I understand results in very slightly more usable power. The vast majority of HeNe tubes have the beam exit from the cathode end.
 

Attachments

  • Green HeNe OC 2 lowres.jpg
    Green HeNe OC 2 lowres.jpg
    99.9 KB · Views: 155
Actually, I saw that ebay auction and recognised the model number too!
Thing is, I already have a green HeNe, shipping to the Netherlands is expensive and this one left me broke (100$ doesn't sound much, but including shipping and customs the total is $300). So I didn't bid on it. Congrats with your new amazing laser :D
 
This illustrates why eBay is "fun" and this hobby is enjoyable for me.

A treasure found for pennies and a "dead" tube brought back to life

Congratulations and good job :gj:

+1

Peace,
dave
 
Yeah I had a lot of fun getting it going. The thing is, as-is "untested" lasers are more often than not tested and confirmed dead. They could be a treasure, but more often they are a paperweight. I wouldn't have bid much more than the opening bid,about what the housing and Alden connector were worth. This one worked out well, but don't bid more than you're willing to throw away on a chance.
 
james1095 said:
Yeah I had a lot of fun getting it going. The thing is, as-is "untested" lasers are more often than not tested and confirmed dead. They could be a treasure, but more often they are a paperweight. I wouldn't have bid much more than the opening bid,about what the housing and Alden connector were worth. This one worked out well, but don't bid more than you're willing to throw away on a chance.
Click to expand...

True words there. Used gas lasers (especially "untested") are quite often simply fancy boat anchors ;)

Peace,
dave
 
You must log in or register to reply here.


Back
Top