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ArcticMyst Security by Avery

M140 Laser Very Dim Help

Joined
Jan 27, 2013
Messages
248
Points
18
Hello, I just built a m140 c6 kit, and powered it up and it was very dim, using 1.8A X-drive round driver I made 3 lasers 2/3 had the same issue. So I took the laser out of the host, and tested the parts individually as well and same issue for the dim diode. I took the diode off connected it to 1.25A rectangular driver and still same issue very dim. The 1.8A driver I took off the M140 I connected that to a 9mm blue diode, and it was full brightness, I used a 7.2A power source, just out of the c6 host incase something in the pill or pill joint is messing things up.
https://www.dropbox.com/s/lbxsacveph9578f/Screenshot 2015-05-14 00.35.10.png?dl=0

the link shows a picture of what I tried. I am wondering if I can get any help, as far as I think the driver is working fine. I checked the diode solders they were shrink-wrapped, except for the neutral one, I am not sure what to do with that. Also the 3rd one I made, is brighter but getting 900mW peak with the fake G2 lens at 1.8A the batteries were charged as far as I remember but recharging them now. I connected everything the same way, as the middle piece (in picture above) and then put into pill and host.
 
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Joined
Jan 29, 2012
Messages
3,164
Points
113
Do you have a PSU where you can regulate current?
Do you have a test load to check the output current of your driver?
Have you checked all the connections and esp the host to driver or battery neg to driver gnd?
Were your batteries fully charged and are they of good enough quality to draw the power you need?

Check for any shorts - If you have a short you could easily fry/LED the diode. Use a DMM to check.
Check the driver out connections L+/L- to the diode pins are solid and well soldered (no dry solder joints)
The case pin is not used and so you can snip this off if you want. It should not contact anything so make sure it is not connected.
Are you usng M140's or the cheaper A140's? If the latter Im not sure whether they cna handle 1.8 A safely.:beer:
 
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Joined
Jan 27, 2013
Messages
248
Points
18
For static electricity, I did not use the blue thing that goes on your wrist as the diode was already pressed into module, I thought that is used when dealing with bare diodes.

I do not have a PSU nor a test load, as for the driver however I cut the leads from the m140 which was very dim, and connected it to a 9mm diode and that was pretty bright, (not in a host with lens so did not measure output, but significant visible difference versus the m140 that was very dim)
I tried these before putting it into the host, so I had 4 joints in total, + and - to the diode leads and to the driver, then I used 2 3.6V batteries in series on a breadboard and manually connected the positive to the centre of the driver and negative on the edge to see if the diode is emitting full power, since sometimes a problem comes in when I press the driver into the pill.

All the joints are covered with heat shrink, I will take it off and check using a DMM.
The case pin is already pretty short, but ill cut it further just to make sure.
I bought 6 C6 kits from daguin with m140 diodes so I am pretty sure these are m140s, the first 3 I made last year in other hosts and they were all over 1.5W. I made one dim one in the winter but got busy with exams and forgot about repairing it as it was very dim and now I completed the remaining 2, out of which 1 works.

https://www.dropbox.com/s/c02bx6gou50kh7e/Screenshot 2015-05-14 11.25.22.png?dl=0

Here is how I have it wired up to a 1.25A driver to test outside of a host, please let me know if I am doing anything wrong here, I let it run for 30 seconds and noticed the heat sink got a bit warm.
 
Last edited:
Joined
Sep 10, 2014
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you got a beam shot so we can see how dim you mean? did the diode LED itself?
you pretty much need a test load to see what the driver is doing
 
Joined
Jan 27, 2013
Messages
248
Points
18
you got a beam shot so we can see how dim you mean? did the diode LED itself?
you pretty much need a test load to see what the driver is doing

I will try getting a beamshot, but last time I tried nothing is projected onto the wall as its very dim. So I tried the floor which was closer. As far as my own diagnostic goes it seems like something is wrong with the diode, because I have tried the driver on another diode (9mm) and it is working fine at 1.8A.
 
Joined
Sep 10, 2014
Messages
1,054
Points
83
well if you tried a different diode and it is bright then most likley the diode got fried. They got super dim when they are done.
 
Joined
Jan 27, 2013
Messages
248
Points
18
well if you tried a different diode and it is bright then most likley the diode got fried. They got super dim when they are done.

sadly thats what I think too, but I am not sure why that has happened, that too for two diodes in a row, and 3rd one was very dim, getting me around 900mW peak on a fake g2 lens. I am using the exact same equipment and leads solder and paste as the 3 I made last year which worked perfectly fine. Even soldering the leads to the diodes were done with a quick tap heat shrink wrapped. The only thing I noticed was that I used un drilled brass pill for C6 previously I made in other hosts with aluminum pills such as C8, C2.

Anyone know if this is possible due to a weak joint between the driver and the pill and then put batteries in. Because one of these I did not test before putting into host.
 
Joined
Jan 29, 2012
Messages
3,164
Points
113
For static electricity, I did not use the blue thing that goes on your wrist as the diode was already pressed into module, I thought that is used when dealing with bare diodes.

If you are soldering the diode onto a driver you will have two bare disconnected leads so effectively a bare diode and you should protect against static.

I do not have a PSU nor a test load, as for the driver however I cut the leads from the m140 which was very dim, and connected it to a 9mm diode and that was pretty bright,
I tried these before putting it into the host, so I had 4 joints in total, + and - to the diode leads and to the driver, then I used 2 3.6V batteries in series on a breadboard and manually connected the positive to the centre of the driver and negative on the edge to see if the diode is emitting full power, since sometimes a problem comes in when I press the driver into the pill.

I bought 6 C6 kits from daguin with m140 diodes so I am pretty sure these are m140s, the first 3 I made last year in other hosts and they were all over 1.5W. I made one dim one in the winter but got busy with exams and forgot about repairing it as it was very dim and now I completed the remaining 2, out of which 1 works.

https://www.dropbox.com/s/c02bx6gou50kh7e/Screenshot 2015-05-14 11.25.22.png?dl=0

Here is how I have it wired up to a 1.25A driver to test outside of a host, please let me know if I am doing anything wrong here, I let it run for 30 seconds and noticed the heat sink got a bit warm.

If a diode is LEDed, aside from a low output, it will get hot very quickly at 1.8 A.

I would recommend investing in a test load to be sure your driver(s) is (are) at this current. Testing with a 9 mm wont tell you if the current is too high as these diodes are much more robust and can handle currents in excess of the recommended max of 2.4 A. If the drivers were too high some of the diodes might be able to handle it and some not, its basically luck of the draw. Those that can cope will probably have a significantly reduced life though. Check with Daguin, but it is possible that you have A140's and some of them were ok whilst the others LEDed. :beer:
 
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Joined
Jan 27, 2013
Messages
248
Points
18
If you are soldering the diode onto a driver you will have two bare disconnected leads so effectively a bare diode and you should protect against static.



If a diode is LEDed, aside from a low output, it will get hot very quickly at 1.8 A.

I would recommend investing in a test load to be sure your driver(s) is (are) at this current. Testing with a 9 mm wont tell you if the current is too high as these diodes are much more robust and can handle currents in excess of the recommended max of 2.4 A. If the drivers were too high some of the diodes might be able to handle it and some not, its basically luck of the draw. Those that can cope will probably have a significantly reduced life though. Check with Daguin, but it is possible that you have A140's and some of them were ok whilst the others LEDed. :beer:

I will keep that in mind, and use the blue static protection thing (sorry for my improper terminology I don't have too much knowledge in this as I am a boomed student)
I guess I can't do much now since the dim part means the diode is gone, just kind of shocked it happened twice in a row, and I have made around 12 lasers in the past and nothing happened. I will get a test load and test out the drivers I have but now I am worried for the one that worked 900mW output using a 1.8A wether I should take it apart and use a lower current driver or leave it at that, I usually get more power using 1.25A driver.
 




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