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FrozenGate by Avery

laser from an old computer

G

Geordie

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May 3, 2015
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Hi, I'm having a problem with my first build and I'm hoping somebody can help me out. So I have set up my circuit effectively the same as the one styropyro has built here: https://www.youtube.com/watch?v=fj7EcDA73Bs, however, when I soldered a 3 ohm resistor across the LM317 chip as shown in the video, the power supply just switched itself off, the same as if the red and yellow leads had touched together. I have now soldered a 66 ohm resistor across the LM317 chip which seems to be the lowest value resistor that can be there without the PSU switching off but the light output of the diode appears to be extremely low to the extent that you can't actually see a dot on the surface it is shining on and you can only see the light from inside the housing of the diode. It may also be important to mention that there were two very similar looking diodes inside the DVD player, both of which i have tried out but they both produce the same result. Will this be a problem with the setup or would I need new parts? The name of the DVD drive is: DVD-116LJ if that is any help
Any help would be greatly appreciated.
 





atx-power-supply-pinout.jpg

If I'm am right, red is +5v and yellow is +3.3v. You need to replace yellow with black(ground) and solder red to lm317
 
Last edited:
Yellow is +12V. Styro got away with using
red and yellow together, but not all power
supplies will allow that. Use black for
negative and red for positive.
 
Thanks man, The circuit is now functioning perfectly although the diode's light output is still very dim, would i need to get a new diode or would this be a problem with the power source? again, thanks for the help
 
The diode is probably toast. 16X DVD
diodes will seldom do 417mA. That and I
have no idea what handling precautions you
had taken during the handling of the diode.
 
I have found videos online that show you how to modify your computer psu to a working multi-volt psu. There is a bit of work involved in turning it in to a bench psu but it can be done. I think that it was instructables is were i saw it but I am not sure. It will be you ports for 3 v, 5 v, and 12 v DC but like I said I am not completely sure. While it is a cheap alternative to a factory built psu I would spend the sixty to hundred dollars and buy a factory built psu. Every once in a while you can find a really good used one on ebay for less than a hundred bucks.
 
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