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ArcticMyst Security by Avery

PHR-805T barely lighting up....need assistance

Joined
Jul 27, 2011
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Okay so I just got in a brand new 805t from modwerx. Hooked it to a rckstr driver and using 2 14500's (totaling 8v input, tested with DMM) and the diode is BARELY glowing. I know it's hooked up right cause if it wasn't it'd be dead by now. So what do you guys think is the issue? Do I not have enough voltage?
 





Joined
May 25, 2010
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You cant Just Hook up a driver to a diode and expect it to work.

You need a testload to make sure you have set the driver at the correct currant.

1 of 2 things could be the issue here.

1) You Ran too much currant to the driver because you dint check where the driver was set too before hooking it up to the diode. Which will make the Laser diode is very dim light. THis is called "I LED the Diode". THis is un fixable and the diode is dead.

2) You got lucky and the driver is lower then the threshold of the PHR-805T and is why its Emitting Dim Light.

There is a Pot on the RCKSTR driver to adjust the driver to the Proper currant for that laser diode.

You should have also picked up one of these from his store:

Laser driver dummy load (test red or blu-ray) [M0001] - $10.99 : Modwerx Shop

^ This is what you hook up in place of the diode to set the correct currant for your diode.

Or you can make your own by fallowing this video here:

When you do this let us know.
 
Joined
Jul 3, 2010
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If you're bad at soldering, its relatively easy to overheat a diode. This happened to me several times, and if it does happen to you... its time to get a new diode. Lazereer is absolutely correct and quite thorough. LED means that the laser diode is so dim, it only emits light, not laser light. And yes, you do need a testload. If your using a PHR, get

6 1N4001-7s and a 1ohm resister at the end of a 6 1n400x in series. Measure millivoltage across the 1ohm resistor to get your current , milliamperes.

End of story...

Iso
 
Joined
Jul 27, 2011
Messages
128
Points
18
is there an easier way to set the current? Anyone have pics with the rckstr driver setting current?
 
Joined
Jan 14, 2011
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No - the only ways to set current are A) by doing math and placing your own parts on the board (hardest) or B) by using a test load to adjust it.
 

Cad602

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Feb 20, 2011
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is there an easier way to set the current? Anyone have pics with the rckstr driver setting current?

It really doesn't get any easier. Just check out This Thread and This thread.

Those and other threads all point to using that dummy load...put it in place of the diode and you won't fry any like I did before I vowed to read all I could on dummy test loads...and I fried a few...

It's real easy man, just take some more time you'll get it..it costs money to learn sometimes (for me apparently) :)

cad602
 

Fiddy

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May 22, 2011
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TEST LOAD OR BAN!

Don't fiddle with the pot or you will certainly LED the diode if you havent already!
 
Joined
Feb 5, 2008
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You people ever noticed how everybody always asks "Is there an easy way?"

Yes! Ofcourse there's an easier way, it's just that we do all the things hard way to confuse the newcomers and for sh*ts and giggles.

The driver you are having is a variable current supply, usable with a wide variety of laser diodes. You have to adjust it for yours.

Construct a test load, set the current, THEN you can use your laser diode, if it's even alive.

Sorry to burst your bubble but it's what the situation is.
 
Joined
Jul 3, 2010
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Eudaimonium, there could be one more option as to why he now has a purple LED.

AFAIK, the circuitry of a laser module, or basically the entire thing is composed of four basic parts.

The diode, the current regulator, power source, and a switch. Those are the four ABSOLUTE BASICS, for a laser to be operational in the least degree.

Now, I would like to go a bit deeper for the switch and driver. As for the driver, it regulates primarily the current, which is why it is called the current regulator. It spits out a constant current from an unregulated power source that could easily destroy your diode, which is what commonly happens. The switch, by definition is a electronic component that break the circuit and prevent any power flowing into the circuit. Just to save power, or for other things as well.

Well the switch is ALWAYS positioned before the driver for several reasons. If you connect it between the diode and the driver, you will do some extreme, unrepairable damage. I am not sure whether the MicroDrive does this but most of DrLava's drivers do. These is called current source mode drivers. If you do connect the switch between the diode and the driver, turning it off will result in a surge (I think, senior members correct me on this one) to your diode, which will instantaneously vaporize your diode. Kaboom!

If you hooked up the diode to the driver and disconnected it DURING operation, before soldering, then this post is your answer. If not, move on. I know this because before I became a semi-amateur-expert, I learned this the hard way, disobeying the driver manual. ALWAYS read the manuals when you are working with different species of drivers.

If all that didn't work then just

Construct a test load, set the current, THEN you can use your laser diode, if it's even alive.
 




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