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ArcticMyst Security by Avery

Will this perform properly?

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Aug 15, 2007
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You can run the red and blue but they focus differently so it doesn't work too well. If the red's in focus, the blue isn't and vice versa.
I get the board off the back by gripping the diode base in vise grips, pulling gently on the board with fine tipped pliers and heating all the solder joints simultaneously with my butane soldering iron's heat blower.
 





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Benny_Hill

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I dont think ive seen a diode come out so easy, but the trade off is that extra heat pulling the back off :-/

Can these diodes be run with no regulator?
 
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Benny_Hill

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I have run harvested reds and IR's from LG burners with no regulator with no problems. I typicaly use 2x33ohm resistors a cap and a diode for polarity reversal. If I do the same with the blues, and restrict the current, what type of voltage should I use 4xaaa for 6v or higher? I was also thinking of using some LR44 button cells instead, seeing as the current draw for the diode is 50ma. Using Gazoo's circuit is probably the safer bet, but its too bulky for what I want to do. If these diodes can handle up to 9v do I have to worry about voltage spikes when using 4 or 5, 1.5v cells?  

I already own blue led's, but  I definately dont want to contribute to the pile :(
 
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PLEASE DO NOT RUN IT WITHOUT A REGULATOR
IT WILL DIE IMMEDIATELY
Build yourself a LM317 circuit and save $27.
When you have a properly set up constant current driver, you need only worry about having over 7 volts input and the voltage to the diode will sort itself out.
 

Benm

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The above schematic would work, but it has some problems..

First of all, i assume its a 78L05 you are using there, which is operating outside of acceptable parameters at 7 volts input. Most -will- work properly with just 2 volts drop, so should be okay.

But do put some limiting resistance in series with that pot - set up like this, turning it to zero ohms will destroy the laser diode, probably instantly.

Also, the antiparalel diode has no use here, can be omitted.
 
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Benny_Hill

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The unfortunate part for the driver is that I live in Canada (eah...) And a trip to The Source (ex-RadioShack) confirmed that the lm317 is not availible here, so I am stuck with their reduced selection products. I went today and the 7805 is the only voltage regulator which they offer. The problem with the 7805 is the size, it's too big. I want to size things down to fit something like a pointer, if I have no alternative I guess ill have to deal with it. Also I put a 33ohm resistor in line with the output, but it was limiting down to 22ma at highest, as where I am running it now at 50ma giving a nice steady 15mw. What are some other options from the bulky driver (if any) as I dont mind a little risk.
 




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