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ArcticMyst Security by Avery

Ok to test diode with AA's?

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Oct 25, 2007
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When I finish soldering up a diode, I like to check the connection with a couple of weak nimh's before siliconing it up.

Is this ok or will it cause some sort of latent fault in the chip
 





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I wouldn't do that if I were you. I know Gazoo would test open cans with AAA rechargeables, but if it isn't an open can I wouldn't try it.
 
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Why open can? (which mine was). I'm sure a voltage spike would be just as harmful to an open can as to a canned ld. Plus its just a quick tap but I suppose thats all it needs.
 

tomcat

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LDs can fail from a millisecond of overcurrent... because of high current electron tunneling inside the chip... or sudden melting of the ld connection hair wires from overcurrent
 
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pocketfluff said:
Why open can? (which mine was). I'm sure a voltage spike would be just as harmful to an open can as to a canned ld. Plus its just a quick tap but I suppose thats all it needs.
Open cans are tougher basically, also remember he was using rechargable AAAs not AAs, the AAAs have a higher internal resistance than the AAs.
 

chido

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Just grab your multimeter and set it to the diode testing function. Place your probes on the LD pins and it should light up, not by much but you should see some light coming out. This will not damage the LD and it's also a great way to find the polarity of the diode's pins if you don't already know. ;)
 
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use 2AA BRAND NAME alkaline batteries and a 7 ohm resistor to test the diode, this will lase most burner diodes brightly :)
 
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Chido's method is THE ONLY SAFE WAY. USING BATTERIES WITH NO DRIVER FOR TESTING IS JUST AS BAD AS USING THEM FOR LONGER USE.
 

Gazoo

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BlueFusion said:
Chido's method is THE ONLY SAFE WAY. USING BATTERIES WITH NO DRIVER FOR TESTING IS JUST AS BAD AS USING THEM FOR LONGER USE.

Stryro is correct too..in a way. I use 2 older AA nimh batteries to quickly test an open can. Unfortunately the diode test on my multimeter does not supply enough voltage to make the open can light up, but it will make a senkat diode light up. Also just because it lights up using the diode function of a DMM does not mean the diode is good, it may have been hit by ESD which turns the diode into a nice LED...most of us know this. So using a pair of crap nimh batteries is ok IMO for the open cans.

Now having said all of this, my harvests from the Sony drive have been so successful I don't bother to test the diodes before mounting them. I have not had one fail (except the first one...don't ask..lol) since I started using ESD protection. This combined with the fact the diode is so easy to remove from the heatsink equals great success.. ;D
 




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