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ArcticMyst Security by Avery

The story of an unlucky PHR...

Joined
Jun 30, 2008
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I got more PHR's today and I decided to harvest one today. It all started like with my two previous diodes, that were succesfully extracted and are still lasing, being victims of my new designs of drivers.

But this time, some of the flexPCB fused together with the solder and I formed a blob of crap around the pins. After trying a bit to remove it, I thought it would be better to use another method to stop heating that poor PHR. I read some time ago about the method jayrob uses, and I copied it. Took my scalpel and with great care I cleaned all the pins until they were perfect. Okay, I thought I had saved the diode because all what was left was breaking the small heatsink around it. But this time, instead of cracking almost instantly, the heatsink supported the pliers's twist and it ended chipped but not broken, leaving no safe grip areas to try another twist. So I took my diagonal cutters and carefully tried to cut the heatsink, but the cutters lost their grip and launched the diode at high speed towards the wall... and well, the heatsink went off but the window of the diode was badly broken... so I decided to de-can it. With great care I removed some of the can to let the glass fragments come out and then I took a macro picture to check if the wires inside the diode were not damaged.




After checking that the wires were OK, I had still to press it inside an aixiz module. Guess what, that went bad too. I use an aixiz back and a small metal ring to press the diode until it's slightly recessed in the module. But as I don't have a vice, I use my own weight as force, applying presure to the back of the aixiz modules with my hands. But this time something went bad and the back of the module sliced and I almost fell. The diode also suffered damage on its pins, that were bent. Two of them were easily straightened but the anode pin, that might be a bit damaged during the harvesting proccess, just broke, ending flush with the diode case. I just used a blob of solder to connect that broken pin to the case, so I could use the case pin as cathode. But as the diode's case doesn't get hot during soldering, that blob wasn't really stuck to the case. I didn't think about that until I connected the driver and, after two minutes of pure awesome 405nm light, when I was happy thinking that I could save that diode, It went off and then I got a big flash and.... LED. The blob had disconnected and made a false contact, making the driver increase the current and leaving the capacitor charged, so when it reconnected the diode was fried.

That was the end of a diode that suffered a lot and ended being a LED. I will never forget it. I hope his two partners that were in the same envelope will be more lucky. At least it had a short but very intense life....


All this story is true, believe it or not.
 





D

Deleted member 8382

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I would go sleep and try again another day lol
 
Joined
Jun 13, 2007
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Wow, that sucks. I hate bad extractions...one time I cracked the heatsink of a PHR and the diode flew out on the floor and the window shattered and the diode was toast.
 

Benm

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Aug 16, 2007
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I'm surprised it survived al this abuse and still worked, apart from the bad contact issue.

One important thing to remember is that heat isn't that big a threat as long as the diode isnt actually operating. Components like these are designed to survive temperatures of up to 200 degrees centigrade for quite some time (tens of seconds at least).
 
Joined
May 21, 2009
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poor diode... mine was it worked for 10 days.. then when i put new an fresh batteries.. it frys too.. i dont know why.. but the current is set only to 100mA.... the diode is still emitting a small dim purple dot with w rectangle yellowish/white thing...
 

Benm

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It might be a wise precaution to put a plastic bac around when you break the heatsink off - especially if you do it in a twisting motion... at least, i suspect its the 'hitting the ground/wall' part that does the damage, not the launch from its heatsink.
 

cust11

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Jun 21, 2009
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It might be a wise precaution to put a plastic bac around when you break the heatsink off - especially if you do it in a twisting motion... at least, i suspect its the 'hitting the ground/wall' part that does the damage, not the launch from its heatsink.

A plastic anti-static bag right? :p

-Mike
 
Joined
Jun 3, 2009
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Yea during one of my extractions, I totally mangled the heatsink, I was SURE i broke it lol
 




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