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12x Murder Fund! + Graph!

ShaneL

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Re: 12x Murder Fund! (Complete!)

Also: Are you going to use some kind of icebox design as a heat-dissipation solution? it seems like it would be safer to use peltier plates for such an expensive diode than just metal.
Since we can't really use a peltier in a typical flashlight style unit, it doesn't really make sense to use one since most hosts have limited passive heat sinking capability.
 
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MISTERWILLING

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Re: 12x Murder Fund! (Complete!)

Then it may be time to design some hosts with tiny TEC's. I have a small TEC from a busted to-3 diode. maybe I will work on a prototype.
 

ossumguywill

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Re: 12x Murder Fund! (Complete!)

Since we can't really use a peltier in a typical flashlight style unit, it doesn't really make sense to use one since most hosts have limited passive heat sinking capability.
yeah, but realistically for the time being it is more likely to be used in lab-style lasers. Also, doesn't wicked lasers use microcontroller-peltier tech in their higher powered lasers? We should find us some round peltier systems...
 

brtaman

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Re: 12x Murder Fund! (Complete!)

yeah, but realistically for the time being it is more likely to be used in lab-style lasers. Also, doesn't wicked lasers use microcontroller-peltier tech in their higher powered lasers? We should find us some round peltier systems...
That was one of the inherent flaws of the Spyder II laser (dunno about spyder III). The peltier would keep the crystals (or diode, dunno what they decided to cool...probably both) cool for a bit of time, but the problem is the sinking.

After a limited amount of time the laser itself would overheat (remember reading long ago some user mention the laser getting HOT quick), due to a lack of thermal mass. The heat itself cannot be radiated fast enough.

When the hot plate of the TEC becomes to hot, the effectiveness of the peltier drops significant, with the "microcontroller" not being able to hold a temperature due to an inherent lack of sinking mass, the stability goes out the window. (Hercules uses active cooling, allowing complete thermal stability over time)

Though these 8X 5,6mm diodes do radiate less heat than a DPSS laser, their need for temperature stability is nowhere near that of a tuned DPSS system.

Another thing to consider is that a peltier is 5-10% efficient and will result in extra heat being dumped into the host (it is not a magical device that teleports heat to a distant black hole), effectively shortening the "duty cycle", very counter-productive.

In our case, limited thermal mass and passive cooling, adding a peltier which would admittedly add a "cool" factor to a host, is not justifiable from an engineering point of view, imo.




BTW: Just read this and the 8X murder thread, AWESOME guys, now this is a community, everyone joining together for the future generations and for knowledge, awesome, everyone who donated to this and the 8X fund, thank you. (BTW You can count on me on the next murder batch or now if there is another fund somewhere. (haven't been reading too actively :())
 
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Tech_Junkie

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Re: 12x Murder Fund! (Complete!)

I think most of you are not getting the "Murder Fund" idea. Its not a longevity test, its a "see how high we can push it" test. Anything under 400mA is wasting time. Most 8X are surviving at that setting. I say start at least at 400mA, then every 10 hours push it up 25mA till it dies.
 

ossumguywill

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Re: 12x Murder Fund! (Complete!)

I think most of you are not getting the "Murder Fund" idea. Its not a longevity test, its a "see how high we can push it" test. Anything under 400mA is wasting time. Most 8X are surviving at that setting. I say start at least at 400mA, then every 10 hours push it up 25mA till it dies.
I say start at 450, because turning the current up after the diode has been used is not a reliable test. A brand new diode may be pushed to higher currents, or it may only be pushed to lower currents. But don't you think we should first hook it up to an LPM, then turn up the current until the output stops climbing? It seems like the way to go, then we get the definite peak current.
 

Tech_Junkie

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Re: 12x Murder Fund! (Complete!)

I say start at 450, because turning the current up after the diode has been used is not a reliable test.
They test all diode pushing them up in steps. In fact, though its not proven yet, it may add to the longevity of the diode.
 

lasersbee

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Re: 12x Murder Fund! (Complete!)

Yeah... no sense in shocking it...
Dave always seems to get Freak high output Laser Diodes...
no matter what type....
Maybe it has something to do with the fact that he ramps
up the current when testing LDs...
I might be wrong... but there seems to be something there.:cool:

Jerry
 
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ossumguywill

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Re: 12x Murder Fund! (Complete!)

They test all diode pushing them up in steps. In fact, though its not proven yet, it may add to the longevity of the diode.
exactly-but we have to give every diode the same opportunity to prove itself. On this, he didn't run it for 120 hours and then turn it up, he turned it up near the beginning. So we have to re-create similar circumstances with a non-degraded diode.
 

Slipstream

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Re: 12x Murder Fund! (Complete!)

I think most of you are not getting the "Murder Fund" idea. Its not a longevity test, its a "see how high we can push it" test. Anything under 400mA is wasting time. Most 8X are surviving at that setting. I say start at least at 400mA, then every 10 hours push it up 25mA till it dies.
Now that's what i call murdering a diode!
 

ossumguywill

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Re: 12x Murder Fund! (Complete!)

Hey guys, speaking of murdering diodes... has anyone here actually tested the physical durability of a diode? It wouldn't need to be expensive, but it would be nice to know at what pressure, shock, moisture level, etc. a blu-ray or DVD burner breaks.
 

HIMNL9

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Re: 12x Murder Fund! (Complete!)

^ Well, if you have 8 or 10 BR 12X burner to throw away, i will be glad to make some of the tests for you ..... :p :D
 

MISTERWILLING

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Re: 12x Murder Fund! (Complete!)

Hey guys, speaking of murdering diodes... has anyone here actually tested the physical durability of a diode? It wouldn't need to be expensive, but it would be nice to know at what pressure, shock, moisture level, etc. a blu-ray or DVD burner breaks.
My 8x pointer went flying across my car and is still fine. I have also dropped the pointers several feet with no consequence.
 

ossumguywill

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Re: 12x Murder Fund! (Complete!)

My 8x pointer went flying across my car and is still fine. I have also dropped the pointers several feet with no consequence.
Yeah, my BR fell about 2.5 feet and it nocked a wire off the switch, but otherwise it was fine.
 

daguin

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Re: 12x Murder Fund! (Complete!)

Yeah, my BR fell about 2.5 feet and it nocked a wire off the switch, but otherwise it was fine.
I've had somebody report that they dropped their laser and it knocked the module loose




Of course it must have dropped into a tool box because there were marks from a pair of pliers on it ;)





And it must have hit the pot because the current was turned up to 400mA :shhh:



Peace,
dave
 




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