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Thread: Post your interesting eBay finds...

  1. #1391
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    Well let it continue then :P

    We're currently discussing the reflectance of OC/HRs and their gains on various lines.

  2. #1392
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    Quote Originally Posted by lasersam View Post
    At first the discharge was sickly pink with no lasing at all, but the type of PMS/REO tubes used in the Ohmeda are unique in that they often recover with run time. And sure enough, this one recovered and is actually higher power than my 7 line Ohmeda, and interesting in that the 650 nm Raman line - which is extremely rare in any HeNe - is similar in power to the 633 line or perhaps even more powerful. The 650 nm line is also stable which is not supposed to be possible.
    I know too little to be fully drawn into the details of rarities in lasers but this gets though even my thick skull. HeNe lasers can make very fine beams like bright needles, and 650 nm is a very beautiful colour. If this stability is replicated in new tubes, there may be small lightshows that would like this because of the exceptionally fine combinations of properties. Not that I imagine you could get power and portability to go with it in desired combinations. And for all I know there may be a DPSS that can do a very narrow well collimated beam close to 650 nm. Diodes and lenses are ok, but I doubt anything like the same beam quality can be had that way.

  3. #1393
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    Quote Originally Posted by SoulFeast View Post
    The title of the thread is "Post your interesting ebay finds". I think a 7 line, working Ohmeda HeNe, that was found on ebay, qualifies. Nowhere did it say that it has to be something currently for sale.
    Perhaps, BUT assuming you're right about a 7 line working HeNe being interesting, AND I agree it is... Don't you think it deserves its own thread?

    Or do you simply enjoy the greater exposure that you get from camping out on a popular thread?
    "There are painters who transform the sun into a yellow spot, but there are others who, with the help of their art and their intelligence, transform a yellow spot into the sun." Pablo Picasso

  4. #1394
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    Hey at least they are posting about interesting lasers that were found on e bay; not complaining about the same. Come on... Now let's find more of them on e bay...I want one. I warn you all though, the powers are very low on these lines. It is just SO cool is the thing...
    Phil Bergeron( AKA 142laser)

  5. #1395
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    Quote Originally Posted by The_Doctor View Post
    I know too little to be fully drawn into the details of rarities in lasers but this gets though even my thick skull. HeNe lasers can make very fine beams like bright needles, and 650 nm is a very beautiful colour. If this stability is replicated in new tubes, there may be small lightshows that would like this because of the exceptionally fine combinations of properties. Not that I imagine you could get power and portability to go with it in desired combinations. And for all I know there may be a DPSS that can do a very narrow well collimated beam close to 650 nm. Diodes and lenses are ok, but I doubt anything like the same beam quality can be had that way.
    These don't get very high powered. I know of 75mW documented, but that was in a lab scenario and not commercially available. Sam can speak more on that. As far as 650, it is a VERY rare line in HeNes. 632.8nm offers the highest output (see first 2 sentences) and the most common as far as availability. After 632.8nm you use a lot of gain from the internal gain. For example, a green HeNe at 3-4mW would blow the knowledgeable away, whereas a 3-4mW 632.8nm would be at, or below average

    Quote Originally Posted by laserist View Post
    Perhaps, BUT assuming you're right about a 7 line working HeNe being interesting, AND I agree it is... Don't you think it deserves its own thread?

    Or do you simply enjoy the greater exposure that you get from camping out on a popular thread?
    I can copy+paste my thread over here, but it was my understanding that this was a more PJ oriented forum, and that such a thread would be overlooked by the major populace, and slowly die. My intention was not to cause a thread jacking, I did not email Dr. Sam asking him to post here and cause a ruckus. The interest sparked was not anticipated. So no, I did not come here to enjoy the exposure. That being said, I do enjoy that others are interested, it is an interesting laser after all.

    If it causes you such displeasure to see posts in this thread, about interesting ebay finds, then I can make another thread about this interesting ebay find, since it apparently does not fit comfortingly in THIS thread about interesting ebay finds.

    Good day

    Quote Originally Posted by 142laser View Post
    Hey at least they are posting about interesting lasers that were found on e bay; not complaining about the same. Come on... Now let's find more of them on e bay...I want one. I warn you all though, the powers are very low on these lines. It is just SO cool is the thing...
    The powers are incredibly low. Consider this, at 1.2mW, it operates in 6-7 lines. Now take out 640 because I'd say it probably does <100uW, and the 652.5nm because it's in and out that leaves 5 lines on an average run. Math dictates (in a perfect ratio) 240uW per line. Now obviously some output more than others, but that also means that power wise, it's nothing to write home about.

    However, it's uniqueness is outstanding, so I love it for that. Plus it's a 7 line HeNe...come on!

  6. #1396
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    Sam and I LOVE HeNe lasers...espacially tunable and multi line...salivate, drool, drool...
    Phil Bergeron( AKA 142laser)

  7. #1397
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    swamidog is offline Jr. Woodchuckington Janitor III, Esq.
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    my first laser was a hene.. this discussion about the multilines is really getting me interested in acquiring a small collection

    Quote Originally Posted by 142laser View Post
    Sam and I LOVE HeNe lasers...espacially tunable and multi line...salivate, drool, drool...
    suppose you're thinkin' about a plate o' shrimp. Suddenly someone'll say, like, plate, or shrimp, or plate o' shrimp out of the blue, no explanation. No point in lookin' for one, either. It's all part of a cosmic unconciousness.

  8. #1398
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    Hene's are beautiful lasers

    The only reason I would suggest for starting a new thread would be so that it can be found easily when doing a search in the future. It's not easily found here
    Quote: "There is a theory which states that if ever, for any reason, anyone discovers what exactly the Universe is for and why it is here it will instantly disappear and be replaced by something even more bizarre and inexplicable. There is another that states that this has already happened.”... Douglas Adams 1952 - 2001

  9. #1399
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    I'll copy it over.

    I actually have a few threads on my multilines. I made a large "reference" thread that has links to all my unique ones (the 3 ML HeNes and the tunable 8 line) and also includes a couple other HeNes I have, and a description.

    I have a project planned to build a tunable, nothing like the 5 time REO LST's, more like 2-3 lines, 4 max, but no way to get 543. Though it won't be for some time, currently studying the basic foundation of the HeNe. After that I'll move into optics, I plan to get a cheap 632.8nm to toy with the adjustment on the mirrors so I can get a feel for how finicky they can be. I don't want to dive straight in a single brewster unit, snag a littrow prism, and get cracking. Too much room for error, and too much fog on the whole concept. Though after I get optics tuning down, I will buy a single brewster and mess with interchanging HRs just for kicks. After that, it's time to tune All that is far ahead, I have a tight budget for this kind of stuff, so baby steps

    I knew you silly PJ heads could be trained :P All joking aside, I'll try to transfer over the thread. I have all the text, but the image embedding process is different over there, no worries though. Should be up in a few

  10. #1400
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    Laser XY Mirror Mount Lasershow Beamtable DPSS Diode HeNe Argon Lot of 16

    http://www.ebay.com/itm/Laser-XY-Mir...item232dffdc48

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