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FrozenGate by Avery

300mW 808nm Laser diodes on eBay for $4.49 free shipping!

GVLLD M981 said:
I got one of these today, and I don't think it works. I soldered it to a module board that used to support a 25mw 780nm laser, but has a pot on it, and in addition, I added an led in paralell, to check the circuit. I'm using a gen 1 night vision scope to check it, and it doesnt seem to do anything. I was wondering if anyone had an idea of what the spectral sensitivity of night vision is? I researched IR laser sights (this is how I came crashing into this p new offshoot hobby, I wanted one, and whomever sets the pricetags on those is on drugs!, and just like that, bang, I'm building lasers, now) the ones that say, say they like the 830nm band, and I didn't like the 780nm band, becasue there was too much bleedover into the visable spectrum (I could see it), I should think 808nm would therefore be a bracketed range. However, this idea was shot down by the 25mw 780nm module that sacrificed it's pcb, anyway, since 25mw hurt my poor nightscope, 5mw would be more than sufficient, I think, but I had big dreams of burning bugs, for this diode, I'm disappointed.
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Don't run diodes in parallel. All of the current will pass through the one with lowest forward voltage drop, which is probably the led. Run them in series, and increase supply voltage accordingly.
 





Mine was not packaged with static protection, so unless 400mA killed it instantly mine is a dud!

I set my Rckstr driver to 400mA with the dummy load and I shorted the cap before I soldered the diode and... nothing.... not even a flash, and I can see 808nm. It's a dim deep red.

Waste of 5 bucks.... I should have gone to Subway instead. :mad:

-Tony
 
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Xplorer877 said:
Mine was not packaged with static protection, so unless 400mA killed it instantly mine is a dud!
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I ordered two and they came wrapped in some cheap foam, no real protection at all. At this point I'll be happy if I can just get one working.
 
AdamCaudill said:
I ordered two and they came wrapped in some cheap foam, no real protection at all. At this point I'll be happy if I can just get one working.
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Got mine todayt too. Same thing, wrapped in some cheap foam, no real protection at all, but in my case I just ordered one... hopefully is functional :undecided:
 
Update:

Okay the second one I ordered is working great. At 400mA it's outputting about 310mW! Not bad for a 5 dollar diode.

I see it as a very deep and faint red. I don't like looking at it because I don't have any IR goggles. But it burns like crazy. I'd say that 400mA is probably the upper limit for a decent life. With just the Aixiz module it gets warm after about 30 seconds and kinda hot after 45 seconds.

-Tony
 
I found a similar diode for 1$ (+ $3.89 shipping) here. The seller is different, but the diode seems same to me.
 
I got another one of these, and I can't get this one to work, either. Is the pinout different than ordinary? I built my own driver, with a variable voltage wired LM317 feeding current control configured EZ1085, which I used (wired the way you would for an LM317, the pinouts are the same) because it has a 1.3v dropout (wanted to use the rated 2.2v for input), and I was out of LM317's, could that be? It's worked for other diodes, allbeit with a fixed 5v. I tried gradually increasing the votage up to 7v in steps, and the current from 5ma to almost 500ma (200 ohms to a limit of 3 ohms from out to adj on the regulator, so 417ma, max- it said it wants 400ma ) at each step, what am I doing wrong? I mounted it a 12x30, so it has some heatsink, and won't burn up, if it ever does light up. I understand now, a couple of dozen diodes later, and I seem to have stopped doing that, finally. And besides, I was watching it, I usually see them go, and I didn't. So I don't get it. I'm scared to try the only other thing I can think of, since that's more current, without at least asking. Either I'm doing something obviously wrong, or these diodes SUCK.
 
808nm laser diodes have the opposite pin out compared to red laser diodes. Case pin is positive.
 
styropyro said:
808nm laser diodes have the opposite pin out compared to red laser diodes. Case pin is positive.
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Yup, but unlike Blu-ray diodes, they WILL survive accidental reverse voltage. I accidentally hooked my 2nd diode up the wrong way, case ground, after powering the diode like this for a minute or so, cursing that again that I got a dud, then I realized what I had done. But I decided to check it just in case. I fliped it around... and waa-laa, 300mW at 400mA!!! :san:

-Tony
 
styropyro said:
^ I would guess that it is single mode considering that it is only 300mW.

Gonna buy one now, would really like to get started in the high powered IR field.
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Do these produce a nice beam or a bar / line? I have had 150mW 808's that are multi as they were only meant for pumping...
 
styropyro said:
808nm laser diodes have the opposite pin out compared to red laser diodes. Case pin is positive.
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Thanks, that was it, allright. But this laser won't burn anything, I have a 5mw 808nm module that seems just as powerful, oh well. You get what you pay for, I guess.
 
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