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ArcticMyst Security by Avery

I CANNOT get my 808nm laser to work!

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Oct 29, 2008
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I've made drivers with LM317s before and never had a problem.  Now I've tried THREE different diodes, and none work.  I got them from Stonetek.  I use my camera on night vision to look for the light - but of course, if it's working, I'd be able to see it with my naked eye too.

My driver setup is the same as it's always been - an LM317 connected to two 10ohm resistors powered by a 9v battery.  I can't think of any reason why it wouldn't work, unless they're all defective, or if the + and - leads aren't the same as they are on a 16x red.
 





daguin

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Have you tried emailing Greg?  I cannot read the JPG of the data sheet well enough to discern the pinout.  Greg says that Hemlock Mike did some work with these diodes.  You could try PMing Hemlock Mike as well

Peace,
dave


[highlight]**EDIT##[/highlight]
Here's the posting by Hemlock Mike

http://www.laserpointerforums.com/forums/YaBB.pl?num=1215907625/17#17

One thing that is evident from just this posting is that the diode is [highlight]case positive[/highlight] so the pinout CANNOT be the same as the 16X which is case negative
 

daguin

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Greenhorn said:
So which is negative?

Since the case pin is positive, one of the other two is the negative. Just hook a diode up temporarily with the case pin connected to the positive lead and try hooking the negative lead up to the others one at a time. You have a 50/50 chance of getting it right the first time ;)

Peace,
dave
 
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808's are used as pump diodes in green DPSS lasers and remember that the batteries are in "backwards". That makes the case +. All of the IR's I've messed with are case +.

Mike
 
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OK, I got it to work, and it burns black stuff when focused.  Excellent. I think I burned out one diode, but the rest work.

It's kind of scary to play with this laser since I know it's bright but I don't BELIEVE it's bright.  It looks awesome in the camera on night vision.  I can't wait to shine it outside at night.
 

daguin

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Greenhorn said:
OK, I got it to work, and it burns black stuff when focused.  Excellent.  I think I burned out one diode, but the rest work.

It's kind of scary to play with this laser since I know it's bright but I don't BELIEVE it's bright.  It looks awesome in the camera on night vision.  I can't wait to shine it outside at night.


SWEET!

Peace,
dave
 
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I could do that.  Stand by . . .

EDIT: I tried, but the cameras just don't work with it very well. With one camera the dot looks like a rather bright white dot, while with my picture camera set to video it looks violet. In reality it is a VERY dim, deep red dot. Also, if I get the laser focused just right and shine it at a black object such as charcoal or black rubber, it produces a bright yellow dot as it burns the material. The camera doesn't pick that up.

It is pretty cool, though to shine it in the dark unfocused with a camera on night vision (so that it can see the infrared). It looks like a floodlight. Even when it has no collimating lens, it lights up things very brightly past 15 meters. It produces a long, narrow beam.

When I focus the laser the best as is possible, the beam still spreads out pretty fast. It stays very narrow, but gets very long, well over an inch at 20 meters.
 
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Yep, All cameras will pick up the light like that if they don't have a IR filter.
 




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