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FrozenGate by Avery
12x Murder Fund! + Graph!
- Thread starter mfo
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Re: 12x Murder Fund! (Complete!)
Where is Dave
Where is Dave
IgorT
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Re: 12x Murder Fund! (Complete!)
Well yea, i also regret not just leaving it alone, but i did a lot of thinking, and let's see what happened here.
- The diode was tested, the PIV data posted. It did 550mW through the "Nichia lens" at 393mA as seen from the PIV plot as well.
- The diode was set to 393mA cos i was told that was the desired current approx three weeks ago. The cycling was started.
- The diode triggered the counter till 251 cycles, where i paused it due to concern the desired current may have changed while i was away. I waited for input.
- I set the driver for 420mA and turned the diode on for a power measurement, using the TEST switch meant for faster replotting.
- The diode was dead by all standards.
The diode was NOT cycled for ANY amount of time at 420mA, it was just turned ON there for a power measurement.
The events could be understood as a quick replot to 420mA with the findings of the diode being degraded to the point of being declared dead for all intents and purposes, from the cycling at 393mA, with the unfortunate side effect that the sensor was unable to detect this death.
What was different from the first 8x experiment? Why am i worried?
I always plotted diodes to higher currents than i tested, altho i did the higher steps quickly so as not to cause any damage.
But in this case, the diode was not tested on the diode analyzer, where the current would be ramped up slowly, but rather powered up to 420mA directly.
IF the diode was alive and well before this point, it MAY have survived a gradual slope to 420mA on the Diode Analyzer, which has prooven to be very gentle when pushing LOCs and LCCs to 400mW and beyond. (But if it was already degraded close to this point, this would not have saved it from further cycling.)
IF the diode degraded to this point at 393mA, the Diode Analyzer would show this immediatelly, even at a low current.
Problem is, we don't know which happened.
But at the same time, thing is, if the diode popped from ONE powerup to 420mA, it would not have lasted much longer if left alone anyway...
On one hand, what we have here is 4h 11m at 393mA and then poof during a short power measurement.
On the other, something doesn't feel quite right, and i would like to redo the experiment, perhaps at a slightly more reasonable current.
What do we know so far? 8x's can be VERY reliable at 300mA, others can degrade before your eyes at almost the same current. Yet another at 50mA more, well, that one needs retesting ASAP.
Diodes vary. But we knew that. I assumed efficiency is a sign of health and in the case of this 12x it very well may have been, altho with my personal 8x it seems as if it's meaningless.
Also, current increases, as "small" as they may seem, might be harsher than we imagine, especially if the second 8x is degrading as fast as i fear (i don't even wanna think about my personal one)...
In the end, all i wanna do is a re-test. And i'm not asking for donations, the personal CR2 laser is pretty much sold.
In the meanwhile, i could reattach the first 8x diode to the torture chamber and let it run to the end side by side with the second one, while waiting for the 12x to come here.
Well yea, i also regret not just leaving it alone, but i did a lot of thinking, and let's see what happened here.
- The diode was tested, the PIV data posted. It did 550mW through the "Nichia lens" at 393mA as seen from the PIV plot as well.
- The diode was set to 393mA cos i was told that was the desired current approx three weeks ago. The cycling was started.
- The diode triggered the counter till 251 cycles, where i paused it due to concern the desired current may have changed while i was away. I waited for input.
- I set the driver for 420mA and turned the diode on for a power measurement, using the TEST switch meant for faster replotting.
- The diode was dead by all standards.
The diode was NOT cycled for ANY amount of time at 420mA, it was just turned ON there for a power measurement.
The events could be understood as a quick replot to 420mA with the findings of the diode being degraded to the point of being declared dead for all intents and purposes, from the cycling at 393mA, with the unfortunate side effect that the sensor was unable to detect this death.
What was different from the first 8x experiment? Why am i worried?
I always plotted diodes to higher currents than i tested, altho i did the higher steps quickly so as not to cause any damage.
But in this case, the diode was not tested on the diode analyzer, where the current would be ramped up slowly, but rather powered up to 420mA directly.
IF the diode was alive and well before this point, it MAY have survived a gradual slope to 420mA on the Diode Analyzer, which has prooven to be very gentle when pushing LOCs and LCCs to 400mW and beyond. (But if it was already degraded close to this point, this would not have saved it from further cycling.)
IF the diode degraded to this point at 393mA, the Diode Analyzer would show this immediatelly, even at a low current.
Problem is, we don't know which happened.
But at the same time, thing is, if the diode popped from ONE powerup to 420mA, it would not have lasted much longer if left alone anyway...
On one hand, what we have here is 4h 11m at 393mA and then poof during a short power measurement.
On the other, something doesn't feel quite right, and i would like to redo the experiment, perhaps at a slightly more reasonable current.
What do we know so far? 8x's can be VERY reliable at 300mA, others can degrade before your eyes at almost the same current. Yet another at 50mA more, well, that one needs retesting ASAP.
Diodes vary. But we knew that. I assumed efficiency is a sign of health and in the case of this 12x it very well may have been, altho with my personal 8x it seems as if it's meaningless.
Also, current increases, as "small" as they may seem, might be harsher than we imagine, especially if the second 8x is degrading as fast as i fear (i don't even wanna think about my personal one)...
In the end, all i wanna do is a re-test. And i'm not asking for donations, the personal CR2 laser is pretty much sold.
In the meanwhile, i could reattach the first 8x diode to the torture chamber and let it run to the end side by side with the second one, while waiting for the 12x to come here.
Last edited:
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Re: 12x Murder Fund! (Complete!)
Even if Igor purchases a 12x for testing, I still think we should open up a new fund. Better to have more for testing than few. Like I said I'm in it for 50$ since I missed the last one.
Even if Igor purchases a 12x for testing, I still think we should open up a new fund. Better to have more for testing than few. Like I said I'm in it for 50$ since I missed the last one.
jayrob
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Re: 12x Murder Fund! (Complete!)
Lets first decide on what current to test it at, and then take contributions...
Lets first decide on what current to test it at, and then take contributions...
Re: 12x Murder Fund! (Complete!)
50$, NICE. I would probably equate to that if I was not 16yr old stuck in school, jobless, but I will grow up eventually.(unless kidnapped by Peter Pan.) But it sounds as if we could easily have 100$ already through as little as 4 users. I agree with you, and say we let Igor do what he wants, buy a diode, and we hold a fund, and get a SECOND. The more the merrier. This will also give us a more averaged perspective as well.
50$, NICE. I would probably equate to that if I was not 16yr old stuck in school, jobless, but I will grow up eventually.(unless kidnapped by Peter Pan.) But it sounds as if we could easily have 100$ already through as little as 4 users. I agree with you, and say we let Igor do what he wants, buy a diode, and we hold a fund, and get a SECOND. The more the merrier. This will also give us a more averaged perspective as well.
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IgorT
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Re: 12x Murder Fund! (Complete!)
Yes, i may want to test the second 12x at a "lower" current. That's also another reason i want to pay for it with a laser of mine (i'll make myself another one anyway) - so i can decide on the current...
We have already shown that 300mA is safe for some (or maybe most) 8x's.
But expecting that 12x's would survive 100mA or even 120mA more than that, may have been unrealistic.
I have another 8x seemingly degrading rapidly at 348mA. Perhaps 360mA would be a good current for 12x's. We might already know what is not.
If nothing else it would at least proove that 12x's are better than 8x's for sure. So far the higher Vf part is still confusing me.
I know everyone wants more power, and as you can see, it all depends on how much life-time you are willing to trade for it.
But we seem to forget how much power we are already getting. There was a huge jump from 6x's to 8x's, but a lot of it came from lenses. The jump from 8x's to 12x's will be a bit smaller.
If i get 400mW+ out of an 8x and 500mW+ out of a 12x with a reasonable life, i will be more than happy. That is also what i recommend when asked, altho the 12x is a guess for now.
Hopefully the second 12x will show that this rapid death was a random fluke, and that they can make reliable >0.5W lasers with some more power to spare.
Yes, i may want to test the second 12x at a "lower" current. That's also another reason i want to pay for it with a laser of mine (i'll make myself another one anyway) - so i can decide on the current...
We have already shown that 300mA is safe for some (or maybe most) 8x's.
But expecting that 12x's would survive 100mA or even 120mA more than that, may have been unrealistic.
I have another 8x seemingly degrading rapidly at 348mA. Perhaps 360mA would be a good current for 12x's. We might already know what is not.
If nothing else it would at least proove that 12x's are better than 8x's for sure. So far the higher Vf part is still confusing me.
I know everyone wants more power, and as you can see, it all depends on how much life-time you are willing to trade for it.
But we seem to forget how much power we are already getting. There was a huge jump from 6x's to 8x's, but a lot of it came from lenses. The jump from 8x's to 12x's will be a bit smaller.
If i get 400mW+ out of an 8x and 500mW+ out of a 12x with a reasonable life, i will be more than happy. That is also what i recommend when asked, altho the 12x is a guess for now.
Hopefully the second 12x will show that this rapid death was a random fluke, and that they can make reliable >0.5W lasers with some more power to spare.
IgorT
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Re: 12x Murder Fund! (Complete!)
I'm going to sleep, so i won't be posting the full 8x Murder Candidate #2 re-plotting results tonight, but i did the test, and...
The second 8x murder candidate degraded to 93% of it's initial power in 6 hours and 10 minutes.
3 more percent to go and it's where the first 8x was at 150h!
Clearly 348mA is not very healthy for them, but the diode is probably capable of more degrading than 10%.
Oh, and since my personal 8x is degrading in front of my eyes, higher efficiency CAN kill diodes faster through more optical flux...
Good night for now.
I'm going to sleep, so i won't be posting the full 8x Murder Candidate #2 re-plotting results tonight, but i did the test, and...
The second 8x murder candidate degraded to 93% of it's initial power in 6 hours and 10 minutes.
3 more percent to go and it's where the first 8x was at 150h!
Clearly 348mA is not very healthy for them, but the diode is probably capable of more degrading than 10%.
Oh, and since my personal 8x is degrading in front of my eyes, higher efficiency CAN kill diodes faster through more optical flux...
Good night for now.
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sightfx
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Re: 12x Murder Fund! (Complete!)
Have you checked the window Igor?
In any case I can toss $20 into the pot. Just let me know where to send it.
-Ryan
Have you checked the window Igor?
In any case I can toss $20 into the pot. Just let me know where to send it.
-Ryan
daguin
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Re: 12x Murder Fund! (Complete!)
I won't be at home again until tomorrow (Tue) morning. However, I will help in any way I can (including a donation).
Peace,
dave
I won't be at home again until tomorrow (Tue) morning. However, I will help in any way I can (including a donation).
Peace,
dave
Svensson
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Re: 12x Murder Fund! (Complete!)
I'm also willing to donate $20 if you guys decide on buying a new diode for testing purposes, since I missed out on the previous opportunity.
And what a shame about the 12× diode, let's hope it was just a bad one. Still it wouldn't hurt to set the next one at a somewhat lower current, just to be sure I guess. By the way, that "smiley" blu-ray dot is giving me the creeps..
I'm also willing to donate $20 if you guys decide on buying a new diode for testing purposes, since I missed out on the previous opportunity.
And what a shame about the 12× diode, let's hope it was just a bad one. Still it wouldn't hurt to set the next one at a somewhat lower current, just to be sure I guess. By the way, that "smiley" blu-ray dot is giving me the creeps..
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Re: 12x Murder Fund! (Complete!)
I'd put it together but people have mixed about me.
:thinking: Wonder why???
I'd put it together but people have mixed about me.
:thinking: Wonder why???
IgorT
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Re: 12x Murder Fund! (Complete!)
I did, even tho it did not look like the window. It's not the window.
The diode is badly degraded. I guess SOME low efficiency 12x's degrade like this.
Seeing how fast the second 8x degraded at 348mA also reassures me a little in the thought that this is the result of the cycling...
And regardless of it's apparent high efficiency in comparison to an 8x, when regarded in it's own group, this is a lower efficiency 12x...
As i said last night, 8x's seem to be reliable at 300mA, 12x's might turn out to be just as reliable at 350-360mA, perhaps there is some more room to move higher, but every 10mA of extra current will cut off more and more hours of life - the life expectancy will drop exponentially with current increase. I do not expect them to be reliable at 100-120mA more than 8x's, especially seeing how some 8x's can rapidly degrade at as little as 320mA...
I did, even tho it did not look like the window. It's not the window.
The diode is badly degraded. I guess SOME low efficiency 12x's degrade like this.
Seeing how fast the second 8x degraded at 348mA also reassures me a little in the thought that this is the result of the cycling...
And regardless of it's apparent high efficiency in comparison to an 8x, when regarded in it's own group, this is a lower efficiency 12x...
As i said last night, 8x's seem to be reliable at 300mA, 12x's might turn out to be just as reliable at 350-360mA, perhaps there is some more room to move higher, but every 10mA of extra current will cut off more and more hours of life - the life expectancy will drop exponentially with current increase. I do not expect them to be reliable at 100-120mA more than 8x's, especially seeing how some 8x's can rapidly degrade at as little as 320mA...
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HIMNL9
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Re: 12x Murder Fund! (Complete!)
@ IgorT:
The sensor that you have used, is just a photodiode or phototransistor that you have used as switch for the counter, or is a photodiode that can be used as level output measurer ? ..... or, in alternative, can you place a simple piece of glass in the beam at 45 degrees, for take out a fraction of the beam ?
If so, you can use a second photodiode and an on-the-fly circuit for "measure" the reflected part of the beam, and have an immediate visual indication if something is happening during the cycle.
I mean, just take an instrument and place the photodiode (or also better, a little photocell) in front of the reflected beam, then regulate the reading on, as example, 100 (no matter the value, the purpose is just to have an indication of any variation, not a precise power reading) ..... this way, you can see the measure, time by time, in "realtime" and notice if the degradation happens during the test on-the-fly .....
Just an idea ..... if you need, i can draw a circuit, for that, and if for any luck you have a photocell, instead a photodiode (or a piece of cell like the ones in solar panels and solar powered calculators), is also better , cause it's a photo-battery, so it need also less or almost no circuitry
@ IgorT:
The sensor that you have used, is just a photodiode or phototransistor that you have used as switch for the counter, or is a photodiode that can be used as level output measurer ? ..... or, in alternative, can you place a simple piece of glass in the beam at 45 degrees, for take out a fraction of the beam ?
If so, you can use a second photodiode and an on-the-fly circuit for "measure" the reflected part of the beam, and have an immediate visual indication if something is happening during the cycle.
I mean, just take an instrument and place the photodiode (or also better, a little photocell) in front of the reflected beam, then regulate the reading on, as example, 100 (no matter the value, the purpose is just to have an indication of any variation, not a precise power reading) ..... this way, you can see the measure, time by time, in "realtime" and notice if the degradation happens during the test on-the-fly .....
Just an idea ..... if you need, i can draw a circuit, for that, and if for any luck you have a photocell, instead a photodiode (or a piece of cell like the ones in solar panels and solar powered calculators), is also better , cause it's a photo-battery, so it need also less or almost no circuitry
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