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ArcticMyst Security by Avery

NEED CIRCUIT HELP!

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i was planning on using this circuit but i need to know if i can use these 10 ohm resistors to substitute for the 2 25 ohm resistors.
 

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Well, according to your picture there is a red beam coming out so I'm assuming you did things right ;D (Quote from VillageIdiot)

If you are going to use two 10 ohm resistors, you are going to have to keep the pot in the circuit. You will have to tweak the pot until you get around 100mA on your multimeter (This is if you are using your 8x diode) It will be easier for you just to use two 25 ohm resistors though ::)
 
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the resistors control the current produced... the lower the resistance, the higher the current going to the laser...

depending on what kind of laser you have you'll want to use different resistors... I'd say hook up the circuit like you planned, but don't connect it to the laser yet, instead hook up 4 regular diodes or a couple of LED's and put a multimeter in series on the "DC mA" setting to measure how much current is going to be going through your laser.

Also, what type of laser are you using? what burner did you take it out of? how fast is the write speed on that burner?
 
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the laser is out of an 8x burner. i was thinking if i used 2 10ohm resistors then i would be getting more current for a higher power laser. i was told i wouldnt be able to push it to hard, but i thought it could hold this much current
 
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well styropyro, i actually havent gotten my modules YET. freakin china... takes too long to ship. lol anyways if i dont use the pot how many 10 ohm resistors would i have to use?
 

rkcstr

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Two 10 ohm resistors connected in parallel would give you 5 ohms and 250mA output current for the LM317. This is probably a little much for your diode. No practical combination of 10ohm resistors will give you something equivalent to 2 25 ohms resistors in parallel, but a single 10 ohm resistor would output 125mA, which may be OK, but I'm not sure.
 

chido

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Then get one, it would be a lot easier than trying to find resistors of the exact resistance you need.
 
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just use one 10 ohm as rckstr suggested. its easier and will work great.
 
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ok i will try it when my diode comes in. also, i think i may have a problem. im using 2 AAA batteries. i think 3V is too low of a voltage for this circuit. tell me an appropriate voltage please?
 
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sk8er4514 said:
just use one 10 ohm as rckstr suggested. its easier and will work great.
That would put out 125mA, a little too high for an 8x. Chido's 12x died at 150mA, so I'm gonna guess 100mA is a maximum for his diode.

dylantevors- You will need something over 6 volts for your laser, 5 AA's works good and so does 2 3.6v RCR123 batteries.
 

chido

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GooeyGus said:
you will need at least 6v for a red laser, and 8v for a violet
Here you're talking about minimum voltage, if you're using a 6v battery with a red diode, then as soon as the voltage drops below 6v, the driver won't be able to provide the diode with the power it needs and thus the laser will get weaker and weaker.
For a red diode I suggest using something that's above 7v and a simple 9v battery for a bluray diode. You're not going to want to use a 9v battery with a red diode because they draw a lot more current than a bluray diode and the 9v battery's mAh rating isn't high enough to power it for a long time, in fact, if you're using one of the new high powered bluray diodes then you're not going to want to use a 9v battery either because these need more current than the weaker bluray diodes.
 
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ok. styropyro, i bought a new diode from stonetek. its a 16x. how should i do my driver for that one?
 

chido

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Build the DDL driver and use 2 10 ohm resistors in parallel, that should drive the diode at 250mA and it should put out around 170mW.
If you want more power then get a 4 ohm resistor, (or a combination of resistors that give you a total of 4 ohms) that should drive the diode at 312mA and it should put out around 200mW.
 




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