IgorT
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Great, some input... :yh:
Bryce and Krutz, i do believe i should proceed more cautiously with the rest of the diodes, because while i know (almost) everyone wants to see extreme powers from their 8x, the purpose of the experiment was to find a "safe" power. Or at the very least try to figure out how long 8x's can survive at the powers we are already setting them to...
We don't know what a "safe" power for 8x's is yet, so there is no point in pushing the other 11 diodes to dangerous levels, just because we see them on the forum, when the exact same plot can be made without even going above the diode's CW ratings! Why endanger them for no good reason, even if it's just for a short time? Datasheets say you shouldn't even do it for milliseconds!
Maybe the future 8x owner from the 8x Mini "GB" wants to run it safelly (and not just "safelly") for a long time, like in a scanner! Additionally, a diode pushed to 500mW during plotting and then cycled at 400mW for a lifetime test, could show worse resuts than if it was never pushed above 400mW in the first place. In that case, the plotting to 500mW+ could skew the results of the 400mW cycler experiment!
That's why i decided, that pushing these diodes in small steps ABOVE their final power - just to draw a straight line - would be stupid, dangerous and unfair to the final owner...
And it would not even tell us anything we can't find out with three completelly harmless steps (Ith + two different powers for slope efficiency, aka differential efficiency)..
Basically i'd like to find a power, where a diode can survive a certain decent amount of hours (on average), where it could last as a laser pointer for a while (like a year of normal use)...
From that "average", people could then further decide, if half as many hours, or even just a quarter is also good enough, if they badly want even more power...
During the "4x = 6x GB" i cycled a 4x diode at ~150mW till death, and it lasted almost 140h or so (don't remember exactly).. I calculated that this would translate into years of use as a pointer - that's why i'd like to find a power where the 8x's would survive for 100-150h.. And i'd love that to be ~400mW..
Now that would be the perfect scenario IMHO. If i get that i'm happy! However i fear i won't, since old 8x's at this powers are already developing kinks! And no one really knows how many hours they have on them. :undecided:
I wanted to ask where you got 8/6 times.. Realized what a stupid question that would be, while typing it
(i was trying to figure out how you calculated it instead of just looking at the numbers :crackup... :yabbem:
I'm working on the following premise: (based on info from Larry's 12x thread)
- 6x's require 100-105mW CW / 200-210mW Pulsed (altho this was not shown there, it was guesstimated for a while and can be assumed if the rest is correct)
- 8x's require 120-125mW CW / 240-250mW Pulsed
- 12x's require 150mW CW / 300mW Pulsed
- 12x's WILL require 225mW CW / 450mW Pulsed (for more layers?)
I couldn't decide between 105-125mW CW for 6x's for a long time, and in the beginning i was even thinking that 8x's could be 150mW CW or more, since i knew people were setting them to 400-500mW! But then i saw the above info LarryDWF posted in the 12x thread, where an 8x diode was shown as requiring 240-250mW! That was when i got worried!
If your calculation was correct however, it would suggest:
- 8/6 x 105mW = 140mW CW / 280mW Pulsed..
But diode manufacturers are probably gonna make (or have made) the next step 150mW/300mW...
However 150mW CW / 300mW Pulsed was presented in the 12x thread for the first 12x's! :thinking:
So let's go with the info from the manufacturer's reports (6x = 105mW, 8x = 125mW) first:
- If this info is correct, it would mean we can push good 6x's to their pulsed power even after a plastic lens!
- We know they last 1 year of my (ab)use there, or several years of normal use (varying from diode to diode of course, but i haven't lost a normal or high efficiency 6x yet, except the one that was abused on purpose)!
- We also know their raw power is around 30% higher, than after plastic lenses (depending on wavelength), so we are actually pushing them to some ~260mW, when seeing 200mW after plastics (with some freaks even more - up to 234mW after plastics = ~290mW raw power)!
So we are pushing them to 2.6x or even 3x (with freaks) their rated CW power! And they oblige...
Let's apply the same factors to the above info:
- 125mW x 2.6 = 325mW
- 125mW x 3.0 = 375mW
And that's raw power, the rest is up to the lenses...
Now assume your calculation (8/6x factor) was correct:
- 140mW x 2.6 = 364mW / - 150mW x 2.6 = 390mW
- 140mW x 3.0 = 420mW / - 150mW x 3.0 = 450mW
The main problem is that we never relly know which diodes we are dealing with. Luckily we can at least test how long they last at different powers...
Otherwise, i wonder how many people realize, that we are already pushing 8x diodes with electrical powers higher than open cans are exposed to!
Sure, the current is lower, at "only" 300mA, but they have a higher Vf and that also matters, when it comes to power (P = U x I)!
0.3A x 5.6V = 1.68W = 0.54A x 3.1V
Setting a diode with a Vf of 5.6V to 300mA is the same as setting an open can to 540mA (since open cans have a Vf of 3.1V)!
If the info from the 12x thread is correct, it's a miracle they are surviving at all. But fact is - THEY ARE?!? Hopefully now we'll also figure out HOW LONG...
Yes, that's what i was thinking yesterday, explained why in more detail above, and that's how i'll do it from now on.
- Simple three point test, just to draw a line and find the weakest two.
- Do a confirmation of the graph on the Diode Analyzer before the plot, to make sure there is no kink there (but WITHOUT going over the power the diode is to be cycled at!)...
- Cycle the first diode to death at 400mW.
- Decide how to proceed based on the results of the first experiment.
- Diodes going to other buyers will only be plotted to the powers the buyers will want from their diode - they will be able to base their decisions on the result of the experiment...
I realize 500mW is the magic number for many people here. Even tho i'd be perfectly happy with 400! But if the results of the first murder allow it, we can test the second one at a higher power of course.
Why are you sending one my way? Don't tease me for no good reason... :yh:
Otherwise, i am ready, and want to test one as soon as we can get our hands on them... :evil:
Does anyone (= you) have a Japanese friend yet? :na:
Bryce and Krutz, i do believe i should proceed more cautiously with the rest of the diodes, because while i know (almost) everyone wants to see extreme powers from their 8x, the purpose of the experiment was to find a "safe" power. Or at the very least try to figure out how long 8x's can survive at the powers we are already setting them to...
We don't know what a "safe" power for 8x's is yet, so there is no point in pushing the other 11 diodes to dangerous levels, just because we see them on the forum, when the exact same plot can be made without even going above the diode's CW ratings! Why endanger them for no good reason, even if it's just for a short time? Datasheets say you shouldn't even do it for milliseconds!
Maybe the future 8x owner from the 8x Mini "GB" wants to run it safelly (and not just "safelly") for a long time, like in a scanner! Additionally, a diode pushed to 500mW during plotting and then cycled at 400mW for a lifetime test, could show worse resuts than if it was never pushed above 400mW in the first place. In that case, the plotting to 500mW+ could skew the results of the 400mW cycler experiment!
That's why i decided, that pushing these diodes in small steps ABOVE their final power - just to draw a straight line - would be stupid, dangerous and unfair to the final owner...
And it would not even tell us anything we can't find out with three completelly harmless steps (Ith + two different powers for slope efficiency, aka differential efficiency)..
Basically i'd like to find a power, where a diode can survive a certain decent amount of hours (on average), where it could last as a laser pointer for a while (like a year of normal use)...
From that "average", people could then further decide, if half as many hours, or even just a quarter is also good enough, if they badly want even more power...
During the "4x = 6x GB" i cycled a 4x diode at ~150mW till death, and it lasted almost 140h or so (don't remember exactly).. I calculated that this would translate into years of use as a pointer - that's why i'd like to find a power where the 8x's would survive for 100-150h.. And i'd love that to be ~400mW..
Now that would be the perfect scenario IMHO. If i get that i'm happy! However i fear i won't, since old 8x's at this powers are already developing kinks! And no one really knows how many hours they have on them. :undecided:
BTW, as far as pushing them to 360mA when testing, I don't think it's a good idea. Here's how I see it, if we assume that improved optics don't play a role (can I assume that? Well I just did), then an 8x would theoretically be 8/6 times more powerful than a 6x. And we usually run GGW's at like maybe 200mA max? So then multiply by 8/6, and you get 267mA. However if these are more rugged or more efficient, then I see why they are being pushed higher.
BTW, I'm totally talking out of my ass here, please correct me (I need to learn!)
I wanted to ask where you got 8/6 times.. Realized what a stupid question that would be, while typing it
(i was trying to figure out how you calculated it instead of just looking at the numbers :crackup... :yabbem:
I'm working on the following premise: (based on info from Larry's 12x thread)
- 6x's require 100-105mW CW / 200-210mW Pulsed (altho this was not shown there, it was guesstimated for a while and can be assumed if the rest is correct)
- 8x's require 120-125mW CW / 240-250mW Pulsed
- 12x's require 150mW CW / 300mW Pulsed
- 12x's WILL require 225mW CW / 450mW Pulsed (for more layers?)
I couldn't decide between 105-125mW CW for 6x's for a long time, and in the beginning i was even thinking that 8x's could be 150mW CW or more, since i knew people were setting them to 400-500mW! But then i saw the above info LarryDWF posted in the 12x thread, where an 8x diode was shown as requiring 240-250mW! That was when i got worried!
If your calculation was correct however, it would suggest:
- 8/6 x 105mW = 140mW CW / 280mW Pulsed..
But diode manufacturers are probably gonna make (or have made) the next step 150mW/300mW...
However 150mW CW / 300mW Pulsed was presented in the 12x thread for the first 12x's! :thinking:
So let's go with the info from the manufacturer's reports (6x = 105mW, 8x = 125mW) first:
- If this info is correct, it would mean we can push good 6x's to their pulsed power even after a plastic lens!
- We know they last 1 year of my (ab)use there, or several years of normal use (varying from diode to diode of course, but i haven't lost a normal or high efficiency 6x yet, except the one that was abused on purpose)!
- We also know their raw power is around 30% higher, than after plastic lenses (depending on wavelength), so we are actually pushing them to some ~260mW, when seeing 200mW after plastics (with some freaks even more - up to 234mW after plastics = ~290mW raw power)!
So we are pushing them to 2.6x or even 3x (with freaks) their rated CW power! And they oblige...
Let's apply the same factors to the above info:
- 125mW x 2.6 = 325mW
- 125mW x 3.0 = 375mW
And that's raw power, the rest is up to the lenses...
Now assume your calculation (8/6x factor) was correct:
- 140mW x 2.6 = 364mW / - 150mW x 2.6 = 390mW
- 140mW x 3.0 = 420mW / - 150mW x 3.0 = 450mW
The main problem is that we never relly know which diodes we are dealing with. Luckily we can at least test how long they last at different powers...
Otherwise, i wonder how many people realize, that we are already pushing 8x diodes with electrical powers higher than open cans are exposed to!
Sure, the current is lower, at "only" 300mA, but they have a higher Vf and that also matters, when it comes to power (P = U x I)!
0.3A x 5.6V = 1.68W = 0.54A x 3.1V
Setting a diode with a Vf of 5.6V to 300mA is the same as setting an open can to 540mA (since open cans have a Vf of 3.1V)!
If the info from the 12x thread is correct, it's a miracle they are surviving at all. But fact is - THEY ARE?!? Hopefully now we'll also figure out HOW LONG...
doing a simple 3 point calculation on all of them first sounds good, for finding the weakest two. without pushing too high, yet.
i agree, cycle the first one at 400mW, if it looks good, the second one at 500mW after optics? i would think this is a magic number for many!
Yes, that's what i was thinking yesterday, explained why in more detail above, and that's how i'll do it from now on.
- Simple three point test, just to draw a line and find the weakest two.
- Do a confirmation of the graph on the Diode Analyzer before the plot, to make sure there is no kink there (but WITHOUT going over the power the diode is to be cycled at!)...
- Cycle the first diode to death at 400mW.
- Decide how to proceed based on the results of the first experiment.
- Diodes going to other buyers will only be plotted to the powers the buyers will want from their diode - they will be able to base their decisions on the result of the experiment...
I realize 500mW is the magic number for many people here. Even tho i'd be perfectly happy with 400! But if the results of the first murder allow it, we can test the second one at a higher power of course.
Are you ready to compare them to the 12x's yet, Igor? :na:
Why are you sending one my way? Don't tease me for no good reason... :yh:
Otherwise, i am ready, and want to test one as soon as we can get our hands on them... :evil:
Does anyone (= you) have a Japanese friend yet? :na:
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