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My 8X at 440mA

yobresal

yobresal

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I have an 8X LG diode in a nice Jayrob kit. It is being fed by a RCKSTR adjustable driver maxed out. I believe the max current is 440mA but I am only feeding it with 8.4 Volts. The power of this thing is incredible. I have used it intermittently for the last 2 days or so. I have seen an almost 10% decrease in power since it's first blast. I have not measured the actual current coming from the driver with the 8.4 Volt power supply so 440mA is just an estimate based on the Rckstr drivers max output. I will post pics and videos soon.
 





Tech_Junkie

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yobresal said:
I have seen an almost 10% decrease in power since it's first blast.
Click to expand...

Acrylic or glass? If you are using glass it might be degrading. Igor says they all degrade at a certain point. Maybe turn the power down some.

mA/mW measurements would be nice.
 
ZRTMWA

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IMHO I think we underestimate the endurance of laser diodes or at least how far we can push them before they LED, even if they have to be used sparingly. You should meter it.
 
daguin

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yobresal said:
I have an 8X LG diode in a nice Jayrob kit. It is being fed by a RCKSTR adjustable driver maxed out. I believe the max current is 440mA but I am only feeding it with 8.4 Volts. The power of this thing is incredible. I have used it intermittently for the last 2 days or so. I have seen an almost 10% decrease in power since it's first blast. I have not measured the actual current coming from the driver with the 8.4 Volt power supply so 440mA is just an estimate based on the Rckstr drivers max output. I will post pics and videos soon.
Click to expand...

At 8.4V you are NOT getting anywhere near 420mA from the Rkcstr with this diode. When I test them, I have to take the voltage to a Rkcstr up to 12V to get full regulation with the 8X diode. 9V isn't even enough!

ZRTMWA said:
IMHO I think we underestimate the endurance of laser diodes or at least how far we can push them before they LED, even if they have to be used sparingly. You should meter it.
Click to expand...

These newer diodes will go straight up to VERY high currents without failing immediately. They just don't last long at those currents

Peace,
dave

**EDIT** @ Yobresal -- If you decide to kick the voltage up, make sure you turn the driver down first. Otherwise you really may hit the poor diode with 420mA!!
 
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daguin

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yobresal said:
Thanks for the clear up Dave, at 8.4 volts how much current do these drives usually put out? here are some videos
Imageshack - img0281 - Uploaded by Yobresal
Imageshack - img0278 - Uploaded by Yobresal
Imageshack - img0283 - Uploaded by Yobresal
Click to expand...

Sorry. I didn't record this. On the first one I tested, I thought the Rkcstr was broken. At 9V, I had it maxed out and I was still only getting 360mA.

I tried it on a second one at 9V and got the same results. Since then I just test these components using 12V.

Since you have >9V, and it is clear that the driver is NOT in regulation there, I would assume it would be less than 360mA

At 360mA with the 4-5-G-1 lens you should still be getting over 450mW out of the laser :eg:

Since it is a Rkcstr you can measure the current by replacing the tail cap with a DMM set to measure mA.

In conversation with drlava, we think we have just found the "edge" of the Rkcstr driver here. The only way to get past this current edge is with more voltage

Peace,
dave
 
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yobresal

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Re: My 8X at ???mA

I just tried that but it maxed out my DMM it only goes up to 200mA. Also I should note that the glass window on this diode has also been removed.
 
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yobresal

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Re: My 8X at ???mA

I am going to go check if there are any decent DMMs on sale today. I have 4 hours of free time each friday.
 
yobresal

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Re: My 8X at ???mA

Outdoor beam shot comparison. >125mW VS >500mW
img02858861557.jpg
 
yobresal

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Re: My 8X at ???mA

Say, does anyone know of a good DMM that can read up to 2 Amps current for a cheap as hell price.
 
jayrob

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Re: My 8X at ???mA

Even with a PHR/rkcstr, 2 X 3.6 (8.4 at full charge) is not a proper supply...

Under load, the batteries will drop below 8 volts very fast. And even with a PHR, the rkcstr driver will need at least 7.25 volts to keep the current setting regulated.

As Dave pointed out, the 8X diode has a higher forward voltage.

I see that some are using 8.4/rkcstr set ups for blu-ray builds, but they will be loosing power as the batteries drain...
 
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