Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

LPF Donation via Stripe | LPF Donation - Other Methods

Links below open in new window

ArcticMyst Security by Avery

Help identifying diodes

Dusty_Lenses

Active member
Joined
Apr 15, 2022
Messages
101
Points
28
Hey folks, I picked up a projector and before tearing it down would like to know what diodes are inside. I was trying to get a xx-V2 but cannot find any locally. I ended up getting a low hour used xx-V10X which is a 3000 lumen model and from memory may have the NUBM42 or similar, but dont want to tear it down if it contains diodes I have already purchased in singles.

The picture and operation is still good and wouldnt mind keeping it as a projector for home use, unless the diodes are worth extraction.

Any idea whats inside this model?
 





Joined
Jul 10, 2015
Messages
9,907
Points
113
A 10 diode block of nubm47-a1 but if you don't know how to harvest the diodes you will destroy them. I have become quite proficient at it but there are a couple of tricks you need to know in addition to basics like circumventing security screws.

It's the xj-v2 that contains 8 of the 44's version 2 while the v1 has 7 of the version 1 which are still good diodes but usually good for 6-6.5W driven @ 4.5A from a low hour pull.

You can buy nubm0e diodes with the window can for under 40 bucks and they are a prettier blue est. 455nm and have virgin pins ( 0 hours ) and I have seen some nubm0A diodes with the window can, they test the highest in my findings so far, same divergence as 44's but can be just a tick stronger or at least just as good but again with virgin pins.

SANY6575.JPG
SANY6581.JPG
 

Dusty_Lenses

Active member
Joined
Apr 15, 2022
Messages
101
Points
28
A 10 diode block of nubm47-a1 but if you don't know how to harvest the diodes you will destroy them. I have become quite proficient at it but there are a couple of tricks you need to know in addition to basics like circumventing security screws.

It's the xj-v2 that contains 8 of the 44's version 2 while the v1 has 7 of the version 1 which are still good diodes but usually good for 6-6.5W driven @ 4.5A from a low hour pull.

You can buy nubm0e diodes with the window can for under 40 bucks and they are a prettier blue est. 455nm and have virgin pins ( 0 hours ) and I have seen some nubm0A diodes with the window can, they test the highest in my findings so far, same divergence as 44's but can be just a tick stronger or at least just as good but again with virgin pins.

View attachment 75083
View attachment 75084
Damn lol.. Thanks for the input. The projector only has 700hrs on it and is fully functional. Only paid 100$ for it, so not too bad of a deal.

Whats the safest method of extraction on these blocks? Ive seen heat used, but I also have a friend with a mill. What would cause more damage do you think, a reflow heat gun or milling the back off?

I have also seen those who carefully break it apart, but im thinking that flexing the base of the diodes may be more problematic?

🍺😋
 
Joined
Jul 10, 2015
Messages
9,907
Points
113
LMFAO @ milling the back off.

1st you have to de-solder the board from the pins, you could use a heat gun and remove the board from all the pins at once, but I like to make cuts between each diode's pins with a razor knife and then I use the solder blob technique along with my favorite 90 degree pick to remove each section of board from each diodes pins, then heat the block with a heat gun and push the diodes out from the back with a straight pick once the indium is soft, you need to heat it evenly and get the diodes out as soon as they are ready, don't overheat it but don't mess around and cook it too long, you can spot heat to finish each diode once the block is sufficiently warmed up.

Keep your diode windows protected/clean or you will be unhappy.


SANY6578.JPG
 

Dusty_Lenses

Active member
Joined
Apr 15, 2022
Messages
101
Points
28
LMFAO @ milling the back off.

1st you have to de-solder the board from the pins, you could use a heat gun and remove the board from all the pins at once, but I like to make cuts between each diode's pins with a razor knife and then I use the solder blob technique along with my favorite 90 degree pick to remove each section of board from each diodes pins, then heat the block with a heat gun and push the diodes out from the back with a straight pick once the indium is soft, you need to heat it evenly and get the diodes out as soon as they are ready, don't overheat it but don't mess around and cook it too long, you can spot heat to finish each diode once the block is sufficiently warmed up.

Keep your diode windows protected/clean or you will be unhappy.


View attachment 75085
Haha you laugh at the milling idea, but its still better than the slingshot / brick wall / magnetic broom idea I had 👀

Appreciate the help. I'll desolder the pins with my iron, then move to the reflow station and follow your instruction.
Thanks again, I hate making mistakes that are costly lol
 
Joined
Jul 10, 2015
Messages
9,907
Points
113
If you set the block on something flat you will push the diodes when the indium melts and they will get re-stuck by the rim of the backing plate in the bottom of the block, **don't do this**, instead put some aluminum foil under the block but leave room for the diodes to fall free when you push them out, I just start heating ( move the heat gun from side to side ) and KEEP CHECKING with my pick to see when their ready, you can spot heat any that need a little more heat.

When the indium melts they will push right out as long as you leave space for them to fall out freely.

Here this will help.

 
Last edited:

Dusty_Lenses

Active member
Joined
Apr 15, 2022
Messages
101
Points
28
If you set the block on something flat you will push the diodes when the indium melts and they will get re-stuck by the rim of the backing plate in the bottom of the block, **don't do this**, instead put some aluminum foil under the block but leave room for the diodes to fall free when you push them out, I just start heating and keep checking with my pick to see when their ready.

Here this will help.

Accidentally deleted my last, thought it posted twice. derp.

Great video, thanks. I was wondering if they easily pop out or needed a good press. Good thing they didnt press fit these as well lol
 
Joined
Jul 10, 2015
Messages
9,907
Points
113
No not press fitted. When you push on them with a pick between the pins they will either pop right out or not, as soon as the indium melts it's like the consistency of a melted chocolate bar.
 

Dusty_Lenses

Active member
Joined
Apr 15, 2022
Messages
101
Points
28
No not press fitted. When you push on them with a pick between the pins they will either pop right out or not, as soon as the indium melts it's like the consistency of a melted chocolate bar.
I meant its a good thing they are not pressed into their seat and soldered. That would be quite tricky.

Ended up setting the block on top of two AL blocks on the edges. Placed a thermal probe in one of the holes of the LD block and gently heated. Popped em out with little issue and didnt exceed 170c .

I tested the diodes prior to extraction, noting down voltage, current, and output of each. Fingers crossed that I got them out safely!
 
Joined
Jul 10, 2015
Messages
9,907
Points
113
A G2 lens is best for power testing and if your reading is low then make sure your lens is clean, I have seen half the output missing because of a dirty lens that didn't look to be all that dirty, but after cleaning with a ZEISS lens wipe I found all the power was there, remember to keep your diode windows protected, I keep my diodes in little containers and limit their exposure to air, when I press one into a module I install a lens right away then solder wires to my pins, the less exposure to open air on your workbench the better and never let your fingers touch the window, they are slightly recessed which helps to protect them, but any contaminants can burn and cause the window to fracture, because all the light from the tiny p/n junction exits the window in a very small spot.
 

Attachments

  • SANY6636.JPG
    SANY6636.JPG
    200.2 KB · Views: 13
  • SANY6637.JPG
    SANY6637.JPG
    198.5 KB · Views: 13
  • SANY6638.JPG
    SANY6638.JPG
    209.6 KB · Views: 13

Dusty_Lenses

Active member
Joined
Apr 15, 2022
Messages
101
Points
28
A G2 lens is best for power testing and if your reading is low then make sure your lens is clean, I have seen half the output missing because of a dirty lens that didn't look to be all that dirty, but after cleaning with a ZEISS lens wipe I found all the power was there, remember to keep your diode windows protected, I keep my diodes in little containers and limit their exposure to air, when I press one into a module I install a lens right away then solder wires to my pins, the less exposure to open air on your workbench the better and never let your fingers touch the window, they are slightly recessed which helps to protect them, but any contaminants can burn and cause the window to fracture, because all the light from the tiny p/n junction exits the window in a very small spot.
The windows of the LD's were clean before extraction, and am not noticing any new spots or lines in the output.
So I think its safe to say they acquired no damage during the extraction. I was worried some flux or indium may splash.

Cant remember where I read it, but there was also correlation to damage based on things like EMF from incandescent lighting
degrading the gain medium. Though I'm not sure what type of shielding was recommended to prevent this. Storage and
environment is definitely worth noting but may only apply to specific gain mediums.

I tested the raw output with no lens, and it appears that there was no damage suffered from heating. The first diode I tested
post extraction was the 'runt of the litter' and yielded :

Pre: 5.2W vf- 4.8V @ 4A Threshold .5A
post: 5.2W vf- 4.8V @ 4A Threshold .5A

I think the key is to heat the block accurately and not exceed the melting point of the indium. I wonder at what temp damage occurs?

A neat experiment would be to sacrifice a diode and heat to specific temps for a set duration repeatedly and try to find
the point where there is noticeable degradation. Taking a guess, I am going to assume that high temps are not as bad as
long as the laser is not on whilst heating. Could very well be wrong on that point though.
 
Joined
Jul 10, 2015
Messages
9,907
Points
113
Mine are doing 6.5W @ 4.5A average through a DTR G2 lens.
I also harvested a couple of V2's with zero hours and those do 7.2W @ 4.5A average with a G2
 

Dusty_Lenses

Active member
Joined
Apr 15, 2022
Messages
101
Points
28
Mine are doing 6.5W @ 4.5A average through a DTR G2 lens.
I also harvested a couple of V2's with zero hours and those do 7.2W @ 4.5A average with a G2
interesting. I'll check that out when mounted. I didn't use a lens initially because the diodes were in the block and didn't want to fiddle.
Was just going for the baseline test prior to heating to see if there was any signs of damage.

The average output was 5.7 - 5.9W @ 4A
 
Joined
Jul 10, 2015
Messages
9,907
Points
113
That's because the divergence is so aggressive......wait, you ran the bare diode up to 4A without being in a module ?
 

Dusty_Lenses

Active member
Joined
Apr 15, 2022
Messages
101
Points
28
That's because the divergence is so aggressive......wait, you ran the bare diode up to 4A without being in a module ?
Only when heating up a cup of coffee!

I ran the first test in the block, then the second test (post extraction) in a testing mount that tightens down with threads instead of a
press fit module. The output was without lens in both tests at equal distance.
 
Joined
Jul 10, 2015
Messages
9,907
Points
113
Yea the divergence is quite aggressive, you could be losing some of your output at the edges, you'll find out when you test with a G2 lens.

I also tested in the block before extraction with the factory gang lens and got a low reading, like 4W, then I cleaned the gang lens with a Zeiss wipe and all the power was there, 6.5W, it's amazing how much loss there is from just touching a lens with our hands and I like to keep my hands clean, still it makes a big difference.
 




Top