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8X Diode Murder fund

sportcoupe

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Can we get back on topic? :thanks:
We can't get "back on topic" because they changed the topic. There will be no murder.
 



Shogoki

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well i wonder if he ever got my email... it's been a few weeks now.. though i sent him an email before he got sick i guess..

oh well.. just popped in because i know i haven't been posting here that often... (just been occupied and stuff)... just waiting patiently and hope that IgorT gets well soon.
 

ZRTMWA

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I don't know if this has been established yet but I found an interesting web page that says the power of the blu ray, red and IR, diodes (or at least claims) when they are running in an 8x burner.

Sony BWU-300S 8x Blu-ray burner

I knew some poeple were wondering a while back before the 12x's came out.
 

IgorT

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Ok, so as i already mentioned in the 12x Murder Thread, the current of the second 8x Murder Candidate (AKA LG 8x #1) was set to 348mA for the cyclng.


The diode was plotted before that, and the power @ 348mA was 453,5mW with a fresh diode.

I posted the Zero Hour plot a while ago. The plan was to do the first re-plot at 10 hours.


The diode was cycled for 6 hours and 10 minutes before i paused it out of concern that 10h might be too much spread out...



I removed the diode from the Torture Chamber and did a complete re-plot on the Diode Analyzer.


Here are the results after 6h10m of cycling....


Power vs. Current Degradation Plot:



Absolute Efficiency Degradation Plot:




Diode Stats:
Ith = 32mA
Slope Efficiency = 1.338mW / mA Avg. (Initial was 1.431mW / mA)
Absolute Efficiency = 21.18% Avg. (Initial was 22.21%)
Po @ 348mA = 422.7mW = 93.21% of Initial Po (453.5mW)



So there it is. We went from 150h+ at 300mA with the lowest efficiency diode of them all, to less than 10h to reach the same level of degradation with the second diode. Well, it's not there yet, but at this rate it will be at 90% in less than 10h.


Clearly the effect of current increase is exponential, and the power can drop as rapidly as i am noticing in my personal 8x.

Some of it will also vary from diode to diode, depending on how tough they are. Regardless of efficiency or current, some will last longer than others, and there are no external factors that can help us determine just how long this will be....



The diode was reattached to the Torture Chamber and the experiment goes on.

I plan to replot it at 8h, where it will probably be at around 90%, after that i plan to let it run till it's dead, so we get the total lifetime as well as behavior before death from it.



Since the 12x diode is busted, i was considering putting the first 8x Murder Candidate back in side by side with the second one and letting it run to get another total of hours.

That could allow us to make a guesstimated projection of how lifetime drops with more current/power....


I need consent from the donors to put the first 8x back in.
 

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daguin

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If we are not going to use it for anything else, we might as well squeeze it for all the information we can ;)

Peace,
dave
 

IgorT

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Re: Lol !

I guess I'm missing something. But, if you would read through the thread, I was the person plotting the percent degradation versus operating minutes on a log-log plot after Igor posted updated data. The last update was when the diode was at 150 hours. It seemed that the updates were determined by Igor which I am fine with.

I was curious if another plot was run or planned to be run or it was just going to be cycled until death.

Looks like I hit a couple nerves. I'll go away.

The first diode was stopped at 150h, because i was expanding the Torture Chamber for the Double Murder Experiment, and also because there seemed to be some confusion as to what to do with the diode...

People had all kinds of suggestions, everything from "push it till it pops" to "turn it into a laser and sell it for LPF"...

I put it aside, cos i was confused, and to be honest, i still am - after this much degradation, i don't see what else it can be used for. At the moment it's just sitting there.

Then there was some delay, cos i was sick, and when i didn't get better i went to the hospital for over two weeks.



Now that i'm back, i completed the Torture Chamber renovations and i'm torturing the second 8x cos that was the next step of the plan. Only thing i still don't know is what to do with the first diode.

From the very start i understood i would get to cycle the diode till it LED's. The name of the thread(s) suggests that as well.


Right now i'm asking for consent from the donors to continue the torture of the first 8x TILL IT DIES, next to the second one while waiting for a replacement for the busted 12x diode.

The reason for this is, that i would very much like to know the final total number of hours and the degradation pattern, for a comparison of the two 8x murder results.



Other than that, i very much appreciated your help with interpreting the results, and wanted to ask for those plots in a higher resolution (the forum allows attaching up to 800x600), as well as more info on how you did the projection this accuratelly with so little data points. If i understand correctly you only had three when you made it and the rest of the data points just fell in place in line with the projection?


P.S. The second 8x Murder Candidate is nearing 10h ON-Time, a re-plot is in order.
 
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jayrob

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You already had that Igor from the beginning! Kill that thing...
 

IgorT

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If we are not going to use it for anything else, we might as well squeeze it for all the information we can ;)

Peace,
dave
I don't see how we could use it for anything else after all it's been through.

What it CAN do is show us just HOW FAR these diodes will degrade before dying, ultimatelly providing a total lifetime (and degradation pattern) to be expected in a laser for this 8x diode at 300mA.

I am hoping the second 8x will die in a similar fashion, following a comparable pattern.



Perhaps we can figure what percentage of power an 8x can lose before it ultimatelly dies....

At higher powers this percentage will probably be a bit lower of course, but that's just one of the things i was hoping to compare...
 




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