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Resolving the 8X BDR sled mess

HIMNL9

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No, the diodes are drived CW for reading, but in reading operation you only need approximatively from 1/50 to 1/100 of the power that you need for burn, so you can't compare it taking the power of reading and the power of writing ..... with good optics, you can read a blu disk also just driving the LD at 10mW.
 



IgorT

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From the original review:
The results from Kendall's initial testing of the diode were different than my results. We need some brave soul(s) to "pony up" and take the chance to test a couple more to make sure that I didn’t get a “freak” but it looks like an 8X to me.

We also need someone to test it with a higher power driver to see if the problems at the end of my test were an artifact of driver problems.

Dave:

I'll be plotting the one sample i got from Kendall today. IF it survives, i'll put it on the cycler (aka "Diode Torture Chamber"), to test the lifetime...


But if it pops... Would you be willing to sacrifice your freak "mystery diode" for the Cycler Cct.? :undecided:


I mean, testing one is never really enough as this example just prooved... This is also the reason why i bought three "150mW Nichia's" for testing. But i can't afford to do the same with these too.. Not now at least...


I can however plot a diode in high resolution within minutes instead of the hours required when using a regular setup, and later test it's lifetime at any desired current automatically...



If yours actually CAN survive high currents, i'd like to see if there are any noticable difference in their PIV characteristics. And for that i'd need to test them on the same setup. :angel:
 

IgorT

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What is the "issue" being "resolved"? Was there a full GB done and completed already?!? :thinking:


People, if you don't know how to contain your excitement, OR if you have to be the first to have one, then you also HAVE to REALIZE that you don't really know what you're buying and are performing an EXPERIMENT!

One diode plot will NEVER be enough to proove anything! Even if that one diode was then shown to survive 200h at 300mW+ it could still just be a random supertough freak.


That is also why i always insist on testing MULTIPLE diodes FIRST!


If you don't want to be a part of the experiment, wait for someone else to do it! Especially if you can't afford it!
Many of us are willing to risk some money in order to learn more. If each gets one diode and does extensive testing, and you read those (multiple) test results FIRST, only then can you expect something to be good. If the (multiple) test results say so.


In Dave's testing thread, we were discussing various POSSIBILITIES, based on the VERY LIMITED findings. One PIV plot is not even a full test! Even if that one diode was tortured to death afterwards it's still only representative of that ONE diode. Several of us expressed concerns right at the start, which Dave reposted here.



It's not the first time a large number of people bought a large number of diodes that turned out to be far below expectations. It probably won't be the last. But maybe the ones who jumped to quickly now will be more careful next time.


I ordered a test diode from Kendall, i paid quite a bit for it, but i also always kept in mind that what i'm doing is an EXPERIMENT! That's why i only bought one. Only if that one performed well, and other people got good results as well would i buy more (and do more tests).



Which reminds me.. I have a test to perform..
Stupid internetz wasting my time... :whistle:
 
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Krutz

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cant wait for more, detailed graphs!

so, did anyone slowly (like in hours) ramp up the current, like dave did and suggests? it shouldnt be difficult to build an automated "burn-in-device", where you dial the goal current (for example 300mA), the steps (5mA) and the total time (3 hours). put your fresh diode in, after 3 hours you may have a tougher diode than before!

its still hypothetical, but if that was the ticket, it would explain a lot! sure, there would be more open questions than before, too..

manuel
 

IgorT

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I don't see what the point of a "burn-in" would be..

I made my Diode Analyzer in order to test diodes faster, not slower. That way i don't have to torture them for hours just to get a plot (the torturing comes after)...


I do not believe the slow testing was what made Dave's diode live. In fact it should be the other way around. If his diode was a weaker one, the duration of the test itself should have killed it.
 

lasersbee

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It is just a theory... no-one has done a side by side test to see if
that "slow turn ON" theory has any weight..
Who knows... maybe Dave's on to something here...:yh:

Jerry
 

IgorT

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I heard of a similar "theory" with PHRs before, but i think we have enough myths in this hobby as it is.

Diodes vary. 405nm diodes vary A LOT. That's all there is to it.
 

daguin

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Dave:

I'll be plotting the one sample i got from Kendall today. IF it survives, i'll put it on the cycler (aka "Diode Torture Chamber"), to test the lifetime...
But if it pops... Would you be willing to sacrifice your freak "mystery diode" for the Cycler Cct.? :undecided:
You got it.

I got a couple more myself to test and may have another member's sled in hand soon. However, I am just back from a couple of weeks of vacation so I have a lot of catching up to do. Also, my Fall semester begins Monday, so I have a lot of preparation to do as well :( Finally, the first week or so of the semester is always busy.

It may be a week or so before I can get to "play" again.

Peace,
dave

P.S. I don't mind being "lucky." I just would like to know if that is what it is.
 

IgorT

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P.S. I don't mind being "lucky." I just would like to know if that is what it is.
I wouldn't mind being lucky either... :angel:


But in this case i am more interested in WHY your diode is seemingly surviving what no other can so far....

I can replot it within minutes for comparison and then put the two side by side on the Cycler, and see what happens - IF mine survives the plotting that is..... I'd add 1.5h to the lifetime of yours, seeing how it took you 3h to plot it, but most of that was under the max current obviously...



Otherwise, my Cycler is currently undergoing a complete rebuild (so it can do multiple diodes simultaneously from a single Cct.), so there is no rush anyway...
 

daguin

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Otherwise, my Cycler is currently undergoing a complete rebuild (so it can do multiple diodes simultaneously from a single Cct.), so there is no rush anyway...
Glenn said that he is preparing a package for you. I will send the diode in aiXiz along with his package.

Peace,
dave
 

LarryDFW

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Hi Drew;

Due to some 6X projects, I haven't even harvested the 8X BDR-S03 yet .

Based on your experience, what current do you think it will operate at for 10 hours or so ?

I was thinking in the 150 to 200 ma range.

Thanks;

LarryDFW
 

IgorT

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Hi Drew;

Due to some 6X projects, I haven't even harvested the 8X BDR-S03 yet .

Based on your experience, what current do you think it will operate at for 10 hours or so ?

I was thinking in the 150 to 200 ma range.
~10h at 150-200mA? That would be the same as a PHR!

Do you expect the BDR-S03 to be of a lower power than the GGWs or even the SF-AWs? In fact even a 4x would in many cases make it for 150h at 150mA...
 

IgorT

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Glenn said that he is preparing a package for you. I will send the diode in aiXiz along with his package.

Peace,
dave
Indeed, he is shipping to me a USPS Express package with a sled from a real 8x drive for FrancoG, something from Jayrob, and maybe some other bits and pieces.

But i was hoping this package would go out today.. Can you get the diode to him today?


If not, Monday would not be too late either.....


Otherwise, thank you VERY much for contributing your diode for extensive testing!
 

daguin

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But i was hoping this package would go out today.. Can you get the diode to him today?
If not, Monday would not be too late either.....
Otherwise, thank you VERY much for contributing your diode for extensive testing!
I spoke to Glenn on the phone. He said that he would get with me (we have some other business to take care of as well) before he sent off your package. I have not heard from him yet, today (Sat)

Peace,
dave
 

BrewCityMusic

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I just got my sled/diode back from Matt - it doesn't seem to have gone LED, just really low powered ... If anyone would like it for "testing" or ??? PM me, I'd be glad to send it out in the name of progress
 

Crossfire

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I just got my sled/diode back from Matt - it doesn't seem to have gone LED, just really low powered ... If anyone would like it for "testing" or ??? PM me, I'd be glad to send it out in the name of progress
Mine did the same thing after a brief bright flash at 290mA. I got 5mW through AixiZ acrylic.

So as to not be a complete loss, I am harvesting the red/IR diodes from this sled. At least I'll make SOMETHING out of it.
 




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