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FrozenGate by Avery

12x Murder Fund! + Graph!

Re: 12x Murder Fund! (Complete!)

Dusty said:
isnt 393mA about 550mW with this diode?:thinking:
Click to expand...


A while ago i asked for people to vote in power and not in current, since these diodes are different from 8x's and same currents might have different meanings.

And YES, 393mA IS 550mW.

Also, before i went to the hospital, i was told most votes averaged around 390mA /550mW by Bryce and a couple of others.


It's not too late to change anything, since i caught this now, but i thought we are right on the spot with the 550mW.


It answers three questions:
- How reliable the 12x's are at 550mW / high efficiency ones at 600mW...
- How much more reliable they would be at 500mW...
- How much leeway there is to go even higher...


That's why i also thought this was the right spot to test. And as mentioned in the first question, keep in mind, this is a low efficiency 12x. Others will push 600mW through the lens at the same current.


Another thing to keep in mind is, this is a 150mW CW diode. At 600mW after the lens, it would be pushing four times it's rated CW power through the lens. And yet the 393mA test will show if the average or better 12x's can do so safelly.


Some of the data will also be extrapolated from the second 8x murder experiment which will hopefully show if and how efficiency influences the survivability of diodes...
 





Re: 12x Murder Fund! (Complete!)

Hallucynogenyc said:
I still would go for 420mA. Btw, I'm glad your back and fine, the forum missed you ;)

I've started a poll here to make sure we get the desired current. IMO 390mA isn't that much. 600mW sounds better :D

http://laserpointerforums.com/f58/current-12x-murder-experiment-47461.html
Click to expand...


Ah, see, i didn't know that, i was working on old data from before i left, and it suggested 390mA...

But i paused it now, and in the morning i will read through it, and then make my final decision.



However, when i started torturing the first 8x, 300mA was my reliability recommendation for an 8x and it worked out fine.

390mA is NOT my reliability recommendation for a 12x, not even close! It's pretty far out, and risky. A few 12x's "surviving" up to 450mA for now means nothing, cos they are being used sparingly.... In the torture chamber time runs much faster...




P.S. 420mA? Why? Cos that's the current open cans are set to? If so, the data point is meaningless, we have to work from what we know.

Altho one thing is the same between open cans and 12x's. Their CW rating - 150mW... But that's where the similarities end...

While they do have the same CW rating, the diodes themselves are completelly different.


For example Vf. Vf of a BluRay diode is way higher than that of a red. Because of that, currents can not be compared between them directly. One would have to calculate the electrical power going into an open can at 420mA (P=UxI), and then divide it with a 12x's Vf, to get a comparable current as a result. And that current would be much lower. A quick calculation shows, that at 228mA, there is as much electrical power flowing into a 12x as flows into an open can at 420mA.
 
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Re: 12x Murder Fund! (Complete!)

"A few 12x's "surviving" up to 450mA for now means nothing, cos they are being used sparingly.... In the torture chamber time runs much faster..."

This is a murder afterall :eg:

Let's see how how long it lasts @ 450mA in your torture chamber.
 
Re: 12x Murder Fund! (Complete!)

Slipstream said:
"A few 12x's "surviving" up to 450mA for now means nothing, cos they are being used sparingly.... In the torture chamber time runs much faster..."

This is a murder afterall :eg:

Let's see how how long it lasts @ 450mA in your torture chamber.
Click to expand...

We called it a "murder", but we don't want it to die so quickly that we learn very little from it. We are searching for survivability, NOT a dead diode.

Peace,
dave
 
Re: 12x Murder Fund! (Complete!)

what if it ends up lasting 600 cycles at that current?


Or i my question is , how many cycles until a current can be called "ok" for a diode?


How are you doing by the way Daguin? Haven't spoke with you in a little while. Any progress with the 2 argon's?
 
Re: 12x Murder Fund! (Complete!)

Slipstream said:
what if it ends up lasting 600 cycles at that current?


Or i my question is , how many cycles until a current can be called "ok" for a diode?


How are you doing by the way Daguin? Haven't spoke with you in a little while. Any progress with the 2 argon's?
Click to expand...

600 cycles? so 10 hours of life? I'd call that very low, and you'll see degradation very soon even with a new diode.
 
Re: 12x Murder Fund! (Complete!)

Slipstream said:
what if it ends up lasting 600 cycles at that current?
Or i my question is , how many cycles until a current can be called "ok" for a diode?
How are you doing by the way Daguin? Haven't spoke with you in a little while. Any progress with the 2 argon's?
Click to expand...

We're looking for 100 HOURS of burn time.

Thos argons are just sitting, collecting dust right now. Showa is a Japan ONLY company. I'm still trying to get a "manual" from them (in Japanese). They do not want to send one to me. If I cannot convince them, then I will try through ABI (the company who's equipment these are being pulled from).

Peace,
dave
 
Re: 12x Murder Fund! (Complete!)

10 Cycled hours.. with 1 min on and 1 min off, i think the frequency of the cycling will have a big impact on how long it lasts and when and how much it degrades.
 
Re: 12x Murder Fund! (Complete!)

Slipstream said:
10 Cycled hours.. with 1 min on and 1 min off, i think the frequency of the cycling will have a big impact on how long it lasts and when and how much it degrades.
Click to expand...

Cycling is just simulation of average normal use.

10 cycled hours has no meaning, cos all the hours will be cycled.

With the first 8x we crossed 150h with 10% degradation and the diode still alive. That translates to years of heavy use.

10 hours on the other hand is not what i would want my laser at.



In any case, what do i set the final current to?

I'm up for 400mA. Any suggestions?
 
Re: 12x Murder Fund! (Complete!)

I was happy with the 393mA, as for me the appeal of a 12x would be to have around 550mW output reliably. If most people would prefere to push the diode harder then perhaps 400mA would be more suitable, but as i said i am happy with it at 393mA...:whistle:
 
Re: 12x Murder Fund! (Complete!)

Slipstream said:
10 Cycled hours.. with 1 min on and 1 min off, i think the frequency of the cycling will have a big impact on how long it lasts and when and how much it degrades.
Click to expand...

When we count time on the cycler we only count time "ON." It is always "60 on; 60 off." A cycled hour would only be 30 minutes on time. We are looking for at least 100 hours of "on" time while being cycled at "60 on; 60 off." That equated to 200 cycled hours in real time.

As IgorT stated above, 150 hours of on time in the cycler takes 300 hours of real time. Our discussions have shown that 150 hours of actual on time (cycled) equates to an average enthusiast's laser use for a year.

Peace,
dave
 
Re: 12x Murder Fund! (Complete!)

Edit: @ Dusty: Well, there's not too much difference between 393 and 400, i think ..... :p ;)



@ IgorT:

First of all, glad to see you're back in health ..... i know what means go around for hospitals (actually i'm in and out for my father, and i'm still on my idea that hospitals are a very good places ..... when you can see them from outside :p :D)

Back to diodes ..... you said that this one that you're testing is the LESS efficent one ? ..... with an output of 550mW "eating" 393mA ? ..... well, this perhaps indicate some improvement in the constructive technology, at least in appearence ..... maybe this also mean that the diode can be overstressed a bit more, but it's just a personal impression .....

Anyway, if i can say a thing ..... as first choice, most have decided to test it at the current that grant 550mW of output, so, for now, why not keep this current and see if the diode can last at least 100 hours (as in the original plot), without loose too much output power ? ..... then, if, as example, you get 100 hours of working time with, say, less than 5% of degradation (i know, i'm an optimist :p), after this the diode can be still considered in good conditions, and if you want, you can change the typology of the test ..... always as example, set it on 420 mA, or similar, and do a second cycle, with the diode more stressed this time, for see what happen (but first, ending at least the first 100 hours cycle ..... changing the conditions in the middle of the test, i'm not sure that can give you significative data)

(BTW, beware ..... in the case you decide to do this, and also the second cycle don't kill the diode, the secret service can cancel your "00" killing license ..... j/k :p :crackup:)
 
Re: 12x Murder Fund! (Complete!)

I predict right now both diodes are going to make the 100 hour goal without dieing. I am sure of this since the currents are being kept to reasonable safe levels. There will be no "murder" here.
 
Re: 12x Murder Fund! (Complete!)

Edit: Yeah I'm a moron. :yabbem:
 
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