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FrozenGate by Avery

Very first red laser build... IM A NOOB!

It should be ok but you are very close to the wattage....but as quickly as alkaline batteries sag it probably will not be a problem. But if it was me I would look for a higher wattage rating. The best I could come up with are these:

http://cgi.ebay.com/2-WATT-WIRE-WOU...ryZ73150QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

They are much bigger than what you need, but it is better to error on the side of caution. I could not find any 1 watt 2.2 ohm resistors.
 





thanks those looks awesome, I think ill get those.

Im not clear on what resistors do, from the name resist im guessing they will cause a voltage drop to the power supply? if thats right then shouldn't i not use resistors because a normal laser diode takes 3v and if i use a resistor that will change my 3v power supply to less than 3v so the diode wouldn't have enough power to burn or shine bright?
 
We don't think in terms of voltage when working with laser diodes. Always think in terms of current. I have run through this many times by testing many different kinds of laser diodes...the GB ones and diodes I have harvested from DVD burners.

Using the resistor will get you started. But eventually you will want to move to a regulated circuit like the one that uses the LM317. The GB diodes can safely run with 250ma's of current using a regulated circuit, and this will get you appx. 150mw's.

Read the following page and look at the pie. This will also help you as you need to have an understanding of ohm's law when working with any hobbies that use voltage,current,resistance and power.

http://www.the12volt.com/ohm/ohmslaw.asp
 
thank you so much that was exactly what i was looking for. Since my high school don't have any electronics courses i have to learn it all from the internet.
 
I'm starting to think I wont be using the 2 MagLite Mini's I got unless I can easily make a driver for them...
 
Ok, i have my Dorcy, waiting on the DX lens and my new diode...

to protect the diode whilst in the dorcy, i have a 47uF 35V capacitor.... I have seen people use 2.5ohm resistors across the poles... is this right? or do i want it in series on the positive? i have also noted people using the 1N4001 (somthing). what is this for?
BTW
Any SUPER, STEP BY STEP with PICTURES FOR THE RETARDED walk throughs? i really want to do this right the first time, haha... buying diodes gets costly for a college kid.

thanks!
~DJ
 
Got my DX lens and housing in today.. WOO! i played with the focusing a bit on the stock red laser before tearing it out.

Now just waiting on my DVD burner.... ;D

the suspense is killing me.
 
Which Dorcy are you using? What kind of batteries does it use?
There are different models and the approach to current-limiting would be different.
(Or did you say somewhere and I missed it?)

And no, you don't want to put 2.5 Ohms across the diode - it would go in series with either lead, but positive might be safer since the case is ground.
 
im using the mini Dorcy with the cr123 battery. 3.0V.

so a 2.5 ohm in series with the positive lead and a 47uf 36V capacitor in parallel and a 1N4001 with reversed polarity in parallel with the leads.

Right?
 
Sounds reasonable to me, although 2.5 Ohms is a guess - every diode is a little different.
A 36V capacitor is fine but may be on the large side. You could get by with a 16V or even a 10V if you want to try to fit it inside the Aixiz module.

Be aware that if you are using the driver circuit that's inside the mini Dorcy (in the hole under the spring), there's a boost circuit and a current regulator. With no load it will let the output rise as high as 5.5V or so. With the LD as a load it will output whatever voltage results in a current of around 300-350ma. (Some Dorcys have been observed to have a higher current output than others.) You probably want a resistor that will further drop that to around 250ma.
Never connect your diode to the Dorcy with the power on - I killed a diode that way. Turn it off and ground the output briefly before you connect to it.
If you take a meter and measure the millivolts across your 2.5 Ohm resistor with the LD connected, you can determine the current (I=V/R) by dividing the millivolts by 2.5 - so 625mv = 250ma. If it's much more than that you may want more resistance. Or you can opt for higher power and shorter lifetime.
There are a million ways of adapting an Aixiz module to a mini Dorcy.
If you want to see the approach I took:
http://barrettmanor.homeip.net:8080/DorcyLaser/Dorcy.html
But keep in mind this one used an open-can diode so I can get away without the current-dropping resistor.
 
Thats excellent information and guidelines there!

Thank you for your assistance! :)
 
i have my DVD diode being extracted right now...

Anyone know if 2 10 ohm resistors in series is good enough to restrict the current for the Dorcy?
 
I'd thinkl that would be a reasonable starting point to see what current you get and go from there.
 
gah.... which diode is the red one? how can i tell? one had a glass lens glued to it... is that the IR one?
 
ok... im not sure which one i should use... i soldered 2 AA batteries up and put some test leads on... i have one where i hook it to typical positive and negative and i dont see anything, then i hook the other one up and i see a dim red light...

at 3V, shouldnt it lase? or am i missing somthing?
 
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