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SenKat's GB LD not burning pls help

cyclonite

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Hello Everyone,

I've just received SenKat's GB LD and I hooked it up to DDL's PSU already. Before I hooked it up, the PSU was putting out 2.8v on the output but I don't know the mA rating as I've never measured it.

Hooked up SenKat's GB LD and now it's showing only a 2.2v reading across the LD and the LD isn't burning anything. it sure is brighter than my laser pointers but even with focusing I can't get it to set a match off.

What should I do next?

Thanks guys ;D
 

Daedal

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How are you measuring the voltage? What is your supply voltage?

Try this for current:

If you have a LD connected to it already, add a 1-Ohm resistor to one of the LD's connections...


PIN FROM DRIVER ------------- -------====------- ----------------- LD connection (positive or ground will work)
1-Ohm resistor

The other connection should go back to the driver unobstructed. (no resistor on the other side)

Use your multimeter and measure the voltage across the resistor you just added... that is your current :)

GL;
DDL
 

cyclonite

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Hi DDL,

Hey thanks as always for your prompt response, do you not sleep throughout the day or what? hehehehe

The thing I'm still trying to understand is this, if you measure the voltage across, what unit will this voltage be in? volts or millivolts? and does this translate to milliamps or amps?

So I should crank up the amps and not the voltage in my case?

Thanks :)

Cheers,

Brian.
 

cyclonite

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Hi DDL,

To answer your question, my supply is 4 very very old CR123 kinda lithium batteries, tested to give out approx 6 volts across 2 of them and about 5.6 volts across the other 2. I do suspect they are old and not as powerful as they should be.

I turned on your PSU (while connected to the LD) and measured the output voltage across the LD leads. This reads 2.4V

Thanks.
 

a_pyro_is

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your supply voltage is probably too low. Use 6 fully charged NiMH cells, or 2 rechargable CR123s and I think you'll be working.
 

Gazoo

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If you bought the prebuilt PSU from Daedal, you will need to run a minimum of 9 volts into it if I recall correctly. Make sure you turn down the pot that adjusts the ma's before you hook up your diode again.
 

cyclonite

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Hi Guys,

I've tried the same with 8 AA alkaline brand new batteries supplying 12V as input but still the diode is only bright enough to act as a super bright pointer but I can't see the beam going out of it and it doesn't burn stuff even with proper focusing.

Any ideas guys?

Thx.
 

amkdeath

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he said measure the voltage across the resistor, NOT the diode, as in:

+ from Driver------- (+ lead on multimeter)-------======------- (- lead on Multimeter)------- + on diode
1 ohm resistor


what does the voltage read now? that is your current.

I am preeety sure u have not enough current, and 2.2V is not enough.

keep your multimeter hooked up (like above diagram) and turn your pot up untill you get 250 mA (something with a 2 and a 5, i dont know, I think it will show .25 on ur MM, or mabe 2.5 I donno, just make sure it has 2 and 5)

also use fresh batteries to get 3V, make sure rectifier, caps, and resistors on driver are working properly.

when all is done, remove 1 ohm resistor, connect directly to diode, and test.

Good Luck,

amk

PS. DONT RUSH, Ive been there be4, when I thought my driver was screwed, be patient, dont hurry to get a burning laser, and dont keep ur laser on too long untill everything is fixed. I was there, and gazoo, SenKat, and the other wonderful members helped me get the problem fixed.
 

cyclonite

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amkdeath:

Alright thanks, yeah I get what you guys mean. I'll go get myself a 1 ohm resistor and try this out :) Thanks for all your explainations.

I'll give this a try again tonight ;D

Cheers,

Brian.
 

cyclonite

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Haahaha alright SenKat,

Ok guys just to re-cap so I don't make a mistake and fry the LD,

1) The voltage reading across DDL's output w/o the LD connected should be around 2.8v

2) The voltage reading across the 1 ohm resistor should translate to about 230mA

3) One the above are correct I'm safe to re-connect the LD to the circuit and try it out again?

Cheers.
 

cyclonite

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I've just been told by DDL that step 3 should be avoided because the mA in the circuit would go up w/o that 1ohm resistor in place :)

Thanks DDL :)
 

Gazoo

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True but it will not go up by much. Nevertheless, I would solder the 1 ohm resistor in place so you always have it when you feel the need to know what your current is...it is the safest most accurate way.
 

cyclonite

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Hey guys,

Alright!! guess what? I've just picked up a '1 ohm' resistor (or so the shop owner claims) however it's a 5 band resistor with blue body and the bands are "Brown Black Gold Gold White" I don't know what it is coz I can't find a calculator that accepts such a weird combination but anyways I'll give this a try tonight.

Cheers.
 




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