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FrozenGate by Avery

1st laser build

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nvmextc

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I built a laser using DDL's circuit the other day on a circuitboard and it has been working well for me.
I'm using a Sony diode from Stonetek. I didn't have a pot so just put in 3x1 ohm resistors in series and I think it's over 200mw
This picture shows it set up to a test load not a diode, I cannot test it though as my DMM is not sensitive enough.
 

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But I want something smaller, so I've connected all the parts up like this,
This time I've used a single 10ohm resistor to hopefully get around 100mw.
 

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Here is a picture of the dot at about 15 feet.
At closer ranges hitting the sweet spot I can burn black plastics, garbage bags, brown matches etc..
 

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And here is an outside shot..
Is this a good way to make a circuit? This is the first time I've made circuits or picked up a solder so I'm just happy it' all seems to be working atm.
 

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Looks pretty good for a first go at it, you might be able to put the components on a small piece of breadboard like in this picture for convenience and to make sure the wires don't short out. A couple of CR123 batteries will put out the same as four AA's and take up less space. Keep on building and making them better and smaller :)
 

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By using a 10 ohm resistor you're feeding the diode 125mA, which is fine but you can still make the laser more powerful.
evilgrin0002.gif

Also, are you using just those 4 AAs? You're going to need 6 AAs, otherwise the driver will start dropping out and your laser will becom weaker and weaker every time you use it.

EDIT: When did you get your diode? Some time ago SenKat got a bad batch of diodes which couldn't handle the same current the good ones could. :(
 
jake: I live in Sydney, Australia, I got the box at JayCar, it cost AU$3.40
trublu: I saw this GB earlier and am dissapointed I missed out http://www.laserpointerforums.com/forums/YaBB.pl?num=1204612696 So could I just get that large board I have, cut it up and put it all close together? Or is a breadboard different in that it connects all the rows? I'm shopping for some recharbale CR's atm as well as the holders for them.
chido: when I had it on 3 ohms it was much more powerful but heated up too quick for long use, I'm waiting to make heatsinks before I make stronger lasers. Yes I'm only running 4 AA's, couldn't find a 6piece holder. So will it actually damage the diode like this or the LM? I might wire up another 2 batteries then till i get some high voltage CR's. I received this diode last week thereabouts. Am ordering a couple more next week.
 
Oh ok, if you got it last week then you have nothing to worry about.
3 ohms would feed the diode 416mA which is WAY too much for the poor little thing. ;D
The maximum current you want to drive your diode at is 250mA by using two 10 ohm resistors in parallel which give you 5 ohms, it'll be a great burner and it'll put out something in the range of 150 to 180mW according to Hemlock Mike's graph. Using 4 AAs won't damage anything, but like I said, your laser is just going to keep getting weaker and weaker every time you use it. The LM317 driver needs at least 6v to work when using a red laser diode, if you use exactly 6v, then as soon as the batteries get discharched the LM317 won't be able to provide the LD with the power it needs. Especially if you use alkalines, because their voltage always drops under a load, so even if you put in new batteries your circuit will start dropping out right away.
 
OK, I've wired in another battery pack in series so I'm running 6 AAA's. and I've added an extra 10ohm resistor in parallel with the other 10ohm.
It's an improvement. It's bright and strong like when I had it on 3 ohm's but doesn't get as hot as quickly now :) The beam is more visible with the lights on. And the batteries seem to last alot longer now.
Seems to be a much better burner now. Thx
 
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