8X Diode Murder fund

[Tech_Junkie]

Ah sorry, I meant readers

 

[sportcoupe]

Dave makes complete sense, as always. Its already past the level of average-high use. Why waste more time just to kill it.

Why? Because these diodes were bought to murder (kill), not to give away when someone says they've had enough.

 

[Tech_Junkie]

We not? We GAVE IT to Igor. It's a failing diode, big deal. Plus if it can make some money for the forum its a double plus.

 

[bryce007]

Plus then he'll have room to test the second 8x as well as the 12x at the same time.

 

[IgorT]

Why? Because these diodes were bought to murder (kill), not to give away when someone says they've had enough.

We not? We GAVE IT to Igor. It's a failing diode, big deal. Plus if it can make some money for the forum its a double plus.

Plus then he'll have room to test the second 8x as well as the 12x at the same time.

What is this about? :thinking:
I really need to catch up with the forum, i've been drowning in work for way too long now.


I thought this was the 8x MURDER experiment. I was kinda hoping to see the diodes die, and not (just) cos i like to see them suffer. We will definitelly see the second 8x die (as well as the 12x most likelly), since it will be at a higher current, but it would be interesting to see the degradation patterns of all of them till the bitter end - it would help predict behavior of other diodes, figuring out how much longer they have to live, as well as making lifetume guesstimates for the currents in between the two experiment settings...


At no point did it occur to me that the first experiment should be stopped after a certain number of hours. The 100-150h thing was just one of my suggestions for a standard of decent reliability in hobby pointer terms.


I do think it would be a good idea to start the second 8x murder experiment now that we know 300mA is pretty reliable, i've been remodeling the torture chamber to start it simultaneously with the 12x, but i was still hoping to see just how long the first one can survive in total, as well as how far and how fast it will degrade (in fact i was working on a way to keep the first one running along with the second two).



While i was considering making a third Torture Chamber position, it might be a good idea to shelve this diode for a while. Not long, just a few days, to see how well the second one does at the higher current. If the results are as surprising as these were, then maybe the first one does still have some life left in it.

If the second one dies too soon, the first one could still be used to get more data out of it.

If the second one turns out to be reliable enough at higher currents, then it really might not be necessary to kill the first one completelly, afterall.


Altho, the goal of the experiment, at least as far as i understood it, was always to find out, just how long can a diode survive a certain current under laser pointer conditions. At least that's how i've been doing it till now (on other diodes).


The fact that the first 8x survived 150h doesn't mean we found the "sweet-spot". If it keeps going on, the sweet spot could be higher up. And to find out how much, the total number of hours would help a lot.

Knowing the total number of hours at one current and then the total at another higher current, would allow guesstimating the inbetween.


I don't know. I need to read the last few pages of the thread, to see what the suggestions were, but i have to finish the Torture Chamber renovations first...

 

[daguin]

The question came up because we were starting to think that maybe this first one would last for months at 300mA. If so, watching it degrade for that amount of time would probably be beyond our usefulness.

Some just want to see it die, no matter if there is any worthwhile science gleaned or not by altering the test conditions (turning up the curent). Others want to have you either build a laser with it to sell (at a discount) to buy another diode (maybe a second 12X) or "raffle" the diode off to one the people who contributed so someone can have longer term benefit from it.

Part of the reasonning is in your own post. We will see one 8X and one 12X degrade to failure with the second test phase. The assumption is that it will be more rapid. If it is not more rapid, then the first will take even longer to die! Killing the first diode, by altering the test conditions, will not give us significant science. It will just be a replication (granted not perfect) of observing the final stages of degradation in the second diode test. Without turning it up, the failure of the first diode may be a long time coming.

Peace,
dave

 

[sportcoupe]

..... Without turning it up, the failure of the first diode may be a long time coming....

Then just let it run till it dies. We need a total number of hours, even if it is over 500. I am willing to wait months. Anyone else agree?

 

[burnerlaser]

Hi, does anyone know why a hommade burning laser diode from a cd burner doesn't work? I accidentally used a 9 volt battery to test it. what should I do.

 

[daguin]

Hi, does anyone know why a hommade burning laser diode from a cd burner doesn't work? I accidentally used a 9 volt battery to test it. what should I do.[/QUOTE]

You should read enough to know where to put your question. Your query is totally unrelated to this thread.

Start by reading the FAQ and the "before posting' threads in the General board

Peace,
dave

 

[Krutz]

many things here! first, a cd-burner-diode is a very bad choice. its not that powerful, but invisible. so it can easily blind you, without you even noticing it! with red ("LOC") diodes and violet ("PHR-803") diodes being around 10$ now, with more output power than that cd-burner-diode, there is no reason to use it at all.
second, you cant simply connect a battery to any laserdiode. it will definitely die, instantly. you need a driver. you can buy those here as well. you just need to decide on what battery (=voltage) you want to use, then get the driver that fits.
read more on this first! all info is here. it will save you your money and parts, and your eyesight.

manuel

 

[ossumguywill]

Hi, does anyone know why a hommade burning laser diode from a cd burner doesn't work? I accidentally used a 9 volt battery to test it. what should I do.

Please read the forums before posting questions, especially such dumb questions.

Anyway-I think you guys should raffle/sell the diode, but maybe that's just because I'm not a cruel bastard who wants to kill diodes.

 

[Tech_Junkie]

I dont know why you guys even bothered answering that idiot.

If the first 8X is not holding up the other test diodes, then fine, let it run. But if it is, dump it, and move on. I think we all know now 300mAs is a reliable setting.

 

[cappernicus]

Igor, are you also checking the spot profile to see how the output changes as it degrades? It might provide useful info to others who have them, but it might also be interesting just to see...

 

[Krutz]

i couldnt wait longer. i built a laser from my diode. slowly turned it up, in 10mA increments, until 350mA with 510mW after a 405-g1 lens!
..which is highly not recommended, the current jumped easily 30mA at the end. fortunately right to 350mA, and not from 340 to 380mA or similar.. phew!

so far its living, with less than one hour runtime. and wow, it burns anything! collimated, not focused! white paper for breakfast!
(no burns on a wall though.. yet)

edit:
this is 20mW more than expected from the graph (diode #8). since my DMM died, i only have my small one, up to 200mA (argh), so i measured 150mA and used a pot as a senseresistor, set so it shows 150mV. the dmm told me the resistor was 1.8R. what the heck. anyway, i wanted classIV anyway. cant be too sure about the current therefore.

manuel

 

[daguin]

i couldnt wait longer. i built a laser from my diode. slowly turned it up, in 10mA increments, until 350mA with 510mW after a 405-g1 lens!
..which is highly not recommended, the current jumped easily 30mA at the end. fortunately right to 350mA, and not from 340 to 380mA or similar.. phew!

so far its living, with less than one hour runtime. and wow, it burns anything! collimated, not focused! white paper for breakfast!
(no burns on a wall though.. yet)

I do :shhh:

Peace,
dave

 

[yobresal]

The wall is actually one of the things in my office at work that I like to burn with my 8X when people aren't bugging me. That and the desk...and my pens, and documents and pretty much everything in here actually.