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ArcticMyst Security by Avery

first 650nm laser

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Will do! I've got a little bracket full of parts to build this and I'm getting excited to start to see it come together. Quick question of I build my own DDL could I power my laser with a 9v battery till the new driver arrives as well as my 2 x 18650 battery holder.
 





AnthoT

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Will do! I've got a little bracket full of parts to build this and I'm getting excited to start to see it come together. Quick question of I build my own DDL could I power my laser with a 9v battery till the new driver arrives as well as my 2 x 18650 battery holder.

9V battery will work fine but very short capacity ;)
 
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Found this little diagram out there and thought it would be a good reference for my to try and build my first circuit on a PCB only thing I noticed is its missing a second resistor in series.
803T%20vero%20layout%20LM317%20driver01.jpg
 
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Well not every DDL is the same :) Not every one of them uses two paralleled resistors.

I think if space is not an issue, building it on a PCB is a good idea. That way you can spread it out and not worry about cramping it.

If you need a diagram of what I would imagine yours will look like on a PCB I can draw that up for you :)
 
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Well not every DDL is the same :) Not every one of them uses two paralleled resistors.

I think if space is not an issue, building it on a PCB is a good idea. That way you can spread it out and not worry about cramping it.

If you need a diagram of what I would imagine yours will look like on a PCB I can draw that up for you :)

that could be helpful. this would be my first time building a circuit on PCB board. i'm pretty experenced with soldering. i've done some pretty trick things like modding xbox 360 controllers and mod chips for consols but this would be my first circuit so a blue print of everything layed out would make if quite simple.
 
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Bah humbug... My drawing skills didn't do it justice so I won't post it.

PCB is more sturdy for building, but it takes up a lot of space.

What I do is freehand soldering. That's just the fancy term for soldering without a PCB.

You could solder it just like in the diagram I posted earlier and that would work well.
 
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Bah humbug... My drawing skills didn't do it justice so I won't post it.

PCB is more sturdy for building, but it takes up a lot of space.

What I do is freehand soldering. That's just the fancy term for soldering without a PCB.

You could solder it just like in the diagram I posted earlier and that would work well.

well your diagram was helpful:thanks:. i don't necessary have to have it on PCB but i thought i would look cleaner as well be a less chance of a break in the circuit. my poteniometer should be here today so i can hopefully start building my circuit and maybe even be lasing today. should i use some heat shrink tubeing around some parts as long as is doesnt cover any electric components? or possiable something else? maybe you have a picture of one you made before.
 
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I don't have any photos of my DDLs. They're all at my mother's house.

BUT I drew a diagram of what it would roughly look like as a free hand soldering job.

7467106578_fd00f7b9d0_c.jpg


This is by no means a clean representation. I'd recommend insulating (Putting heatshrink or electrical tape) the pins of the LM317 after the correct components/wires have been soldered to it. Also, any other solder joints which will move such as the wires connecting the resistors, potentiometer, and the capacitor and diode.
 
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I don't have any photos of my DDLs. They're all at my mother's house.

BUT I drew a diagram of what it would roughly look like as a free hand soldering job.

7467106578_fd00f7b9d0_c.jpg


This is by no means a clean representation. I'd recommend insulating (Putting heatshrink or electrical tape) the pins of the LM317 after the correct components/wires have been soldered to it. Also, any other solder joints which will move such as the wires connecting the resistors, potentiometer, and the capacitor and diode.

thats a perfect templete to work from, one question though is there a difference between having the resistors before the the pot or after? i see you have it after which makes sense to me but i've also see where its before the pot.

and today i made another trip up to radio shack you pick up some extra IN4001's and a 1 ohm resistor to make my test load but they dont carry 1 ohms unless i buy the 600ct variety pack:wtf:. the closes they have is 2.2 ohm. if i run them in parallel i would get 1.1 ohms, is there a way to make that work? i also have a diode that came from another dvd burner less then 16x that i dont really care to much about just used it to practive extracting it from the heatsink and what not. could i use that in place of a test load.
 

AnthoT

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thats a perfect templete to work from, one question though is there a difference between having the resistors before the the pot or after? i see you have it after which makes sense to me but i've also see where its before the pot.

and today i made another trip up to radio shack you pick up some extra IN4001's and a 1 ohm resistor to make my test load but they dont carry 1 ohms unless i buy the 600ct variety pack:wtf:. the closes they have is 2.2 ohm. if i run them in parallel i would get 1.1 ohms, is there a way to make that work? i also have a diode that came from another dvd burner less then 16x that i dont really care to much about just used it to practive extracting it from the heatsink and what not. could i use that in place of a test load.

You shouldn't need a test load if you make your DDL circuit correctly :) but you should try & get 1 ohm resistors :) probably on eBay for real cheap, you may be able to use that diode as a test load but only to a certain point ;)
 
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Nope, the order of the resistors and potentiometer don't matter as long as he 10 ohm resistors are paralleled to make 5ohms.

Out of curiosity, what is your pot rated at?

I'm heading out camping in the morning so I'll be away from my PC and won't be able to respond. But Anthony here seems to be able to answer your questions just as well, if not better!

Best of luck!
 
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100 ohm. I've search around and they say 100 ohm is the way to go as it gives you the ability to adjust the power better. Have fun camping, I just took my family last weekend and the weather was perfect, so have a good time and be safe. :D

And that's for all your help.
 

AnthoT

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100 ohm. I've search around and they say 100 ohm is the way to go as it gives you the ability to adjust the power better. Have fun camping, I just took my family last weekend and the weather was perfect, so have a good time and be safe. :D

And that's for all your help.

100ohm is perfect ;)

I can't wait to go camping this year :D last year one day got really hot with the humidity & I couldn't sleep at all so I jump in the lake at around 4 Am & the lake was warm :p other then that day it was great
 
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well i got my circuit built. just finished it up. had a problem where it wasn't working correctly and i figured it out pretty quickly, i put the capacitor in backwards. i was able to power a low X dvd burner diode as well as a led, and the potentiometer works great. my problem i'm having now is my cheap ass harbor freight tools multimeter doesn't have the right setting to figure out how much mA i'm pushing, or i'm not seeing it. but its late so hopefully tomorrow i can post a picture.
 




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