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ArcticMyst Security by Avery

LF Red Dummy Test Load

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Sep 4, 2009
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Hey guys, looking for a used test dummy load as im building a red laser.

i really wish there was an easier way to set the current on my flexdrive, but i know ill need a test load for it...

If anyone has a spare laying around, hit me up - ill take it.

Thanks

Tom
 





Joined
May 10, 2011
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Modwerx has em for 10$ but I think you can only set them up to like 500ma I have one there nice

Edit,: just saw u were a Aussie shipping int. From modwerx is expensive so forget that if you don't want to make your own ( its not very hard ) ill sell u mine
 
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Dec 28, 2010
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I could whip you one up real quick, but I'm no master builder so it would be just 6 diodes on a perf board with wires coming out... International shipping would be like $7, so I suggest you grab some diodes (I forgot what kind, 1N4004 or something) and put 6 of them in series, put a lead on the 3rd one so you have 4 in series for reds... Extremely easy to do with the tut that ARGlaser posted.
 

GBD

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Oct 25, 2010
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Best and cheapest thing is to follow ARG's link for the schematic, go buy yourself a 1ohm 5W wire wound ceramic resistor, and a pack of 1n4001 diodes (so 4 in series for Vfwd typical for 660nm).

Thats really as simple as it gets and the circuit can be build in seconds without any specail tools. (and later you can change its layout for other diodes)
 
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OK - So for a red dummy load, can someone pretty much tell me exactly what I need to build a test load?

What parts? Ill go after work and pick them up.
 

GBD

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A pack of 1n4001 diodes, 1ohm 1W-5W resistor, some wire, and preferably if you have soldering tools, for a bare bones setup.
 
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Feb 9, 2011
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For a red you need about 2-3 diodes depending on the forward voltage of the laser diode.

Since your going to be using a Flexdrive your diodes don't need to match the exact voltage, but close to it.

So, grab 2-3 1N4001 diodes in series with a 1 ohm 2 Watt resistor or higher (higher wattage is a must if your driving higher currents). Connect the ends to your driver and with your multimeter measure the voltage across the resistor and that will be the current output of your driver.
 





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