12x Murder Fund! + Graph!

Re: 12x Murder Fund! (Complete!)

dang this is sour news

Re: 12x Murder Fund! (Complete!)

Meatball said:

IgorT, just so you know, I've had a 12X running at 305mA for several hours now. I'd say about 4-5 to be exact. That was before something got burned onto the diode window. Flaminpyro has just successfully cleaned it, and will be testing the output very soon.

I know it's not set very high, but I run my lasers for long periods of time.

Click to expand...

I guess i should have been clearer before betting my life on anything. :yabbem:

Obviously i meant at the very high currents around 400mA....


305mA for a 12x is what i would consider extremelly safe. Normally i would recommend 400mW+ for 8x's and suggest a 12x if 500mW+ was desired.

Meatball said:

I guess I don't believe in duty cycles! I believe in BIG heatsinks though!

Click to expand...

Then we have something in common. :yh:

Re: 12x Murder Fund! (Complete!)

Igor check your PM.

Re: 12x Murder Fund! (Complete!)

do you really think it was the current which killed it? :S

Re: 12x Murder Fund! (Complete!)

Hallucynogenyc said:

do you really think it was the current which killed it? :S

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perhaps this was just a weak diode...:undecided: other than that I do not know what could have killed it.

what is your theory?

Re: 12x Murder Fund! (Complete!)

yea I think we should have left it where it was. Now it's a zombie and we don't know why, because we introduced another variable by upping the current.

Re: 12x Murder Fund! (Complete!)

IgorT said:

I guess i should have been clearer before betting my life on anything. :yabbem:

Obviously i meant at the very high currents around 400mA....


305mA for a 12x is what i would consider extremelly safe. Normally i would recommend 400mW+ for 8x's and suggest a 12x if 500mW+ was desired.




Then we have something in common. :yh:

Click to expand...

Yes, it is quite conservative. I got it put together when we were all still unsure of the diode.

We didn't know if it was an 8x diode, or even something lower in power.

But from the sound of it, some 12xs don't really like 420mA, and some don't seem to care so much.

Good luck with testing!

-Tyler

Re: 12x Murder Fund! (Complete!)

bryce007 said:

we introduced another variable by upping the current.

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This is true. In any case another diode will have to be purchased to experiment further.

Igor is saying he will sell one of his lasers to pay for another diode. IMHO I think that this is unacceptable, Igor is doing everyone here a favour by doing these experimants, so we should not let him pay for a new one. I think that the cost should be spread over the number of people who wish to see the results.

Do people agree with me on this?


EDIT: I just looked at the picture of the 'face' diode...very strange, lol

Re: 12x Murder Fund! (Complete!)

Well, if the diode is dead, i'm sad for the experiment and for our expectances ..... and if i can, i add something if he want to start a second murder fund collect ..... but, let me say ..... if that pic is not photoshopped , it's the more damn weird way that i've ever seen from a diode to say you "i'm dead" ..... i mean, look at that "face shape", it lack only a tongue .....

:crackup: :crackup: :crackup:

Re: 12x Murder Fund! (Complete!)

Why was the current changed 4 hours into the experiment? I "thought" that was a completely wrong thing to do and I even got chastised for suggesting it in the first 8x murder experiment.

Re: 12x Murder Fund! (Complete!)

I don't know why it was changed... Perhaps the 12x murder poll had something to do with it. I don't know if we can learn anything from what has happened so far...

Re: 12x Murder Fund! (Complete!)

jayrob said:

If you spend money on a second one Igor, you may want to consider turning it down to 360mA's...

After alll, it's not your fault it died at 393mA's... That's the result of the test at 393mA's for that particular (low efficiency 12X) diode...

Click to expand...

In theory, it could be that the 4h of 393mA did this. It's extremelly unlikelly one 420mA powerup would kill the diode.

But if so, it would be quite scary. 12x's SHOULD survive more than 8x's, shouldn't they? 390mA was my halfway safe bet...


But unfortunatelly i screwed up the test protocol. I did not do an inbetween test, so i can't know for sure.

I didn't do it, cos i didn't expect one 420mA powerup to kill the diode, all i was trying to do was measure the power, to determine the top point and do a simple re-plot.


Had the diode survived, the test would also show if the previous cycling did any damage, and if a complete replot was necessary.


If anything, i would have expected a tiny drop in power. But a complete deformation of the beam?!?

The miracle here is, that this weird thing is still lasing, that it produces a perfectly round beam with holes in it, but one that could still burn! :thinking:


I only once saw degradation like this without death, and it was on a PHR that lost almost half it's power in the hands of a buyer, over a couple of months... The beam profile was similar...



In any case, i don't want to believe that a 12x would degrade this quickly at 393mA, even tho i was slightly scared of this current.

But on the other hand, expecting that every single diode will degrade in the exact same way as the first test 8x...

I don't know, this is weird.

Re: 12x Murder Fund! (Complete!)

sportcoupe said:

Why was the current changed 4 hours into the experiment? I "thought" that was a completely wrong thing to do and I even got chastised for suggesting it in the first 8x murder experiment.

Click to expand...

It got changed, cos people expressed different wishes.

4 hours did not seem much in comparison to the 150h+ we got from the first 8x diode. I did not deem it important. (The chastising was done as that 8x neared 100h...)


The reason i want to sell one of my lasers and redo the experiment is, because i did not do a complete replot ON THE DIODE ANALYZER when i paused the cycler, to find out the results of the poll.

On the other hand, the TEST switch i built into the new Torture Chamber was meant to simplify replotting after we've learned that Ith doesn't move - the top point with a cold diode should be enough to replot it completelly.

For me, flipping it equated a simplified replotting up to a slightly higher current that seemed one of the most desired possibilities... With the first 8x i also kept replotting it 20mA higher than was tested.


I did not expect the 27mA more to do this at the flip of the switch. It's actually more likelly that the previous cycling did it.
Had i flipped the switch and saw this before changing the current, i would declare this the end of the 393mA experiment.


But i can't be sure, which is why i want to buy another diode and redo the experiment. Perhaps at a more reasonable current possibly based on some observations of other members with their 12x lasers made by the time the diode gets here.



So anyone with a 12x laser, please post here if you notice ANY power loss, regardless of how small.

I keep noticing the power of my 8x dropping bit by bit. If 400mA is too much for 12x's, people who set them there should hopefully notice it.

Re: 12x Murder Fund! (Complete!)

There are also some news about the second 8x diode.

It seems to have degraded quite a bit (but at least the beam profile is still normal).

It's been cycling away at 348mA for 6 hours, and a quick test showed the power a lot lower than the zero hour plot shows.


I need to wait for it to cool down, but it's quite possible we are expecting too much of these diodes.


150h and still going is a lot. 6 or 4 is not. But it's enough to fool us into thinking it works. With a short enough duty cycle 4 hours can last a month or more. Besides, some would obviously last longer than others, maybe up to 20h or a bit more... This was a low efficiency 8x and 12x....


We shall know more when the 8x cools down.

Re: 12x Murder Fund! (Complete!)

I would be happy to contribute another $20 dollars for a second 12X, but I would want it at 360mA's...

I was one of the ones that never wanted to see the first one pushed so high...

Re: 12x Murder Fund! (Complete!)

I'd throw another nickle in the pot. Maybe someone should start a new fundraiser thread.