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FrozenGate by Avery

GB: PL520 murder fund






ApexProxy said:
I would love to see what -50C would do to wavelength on a PL520 and to a M140.
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Yeah that was my whole reason for suggesting it was to see what unique wavelength might come from it. It sounded like a better Idea in my head but it definitely is way over board,complicated, and expensive.
 
Zathras said:
How about using a CO2 fire extinguisher?

The CO2 is delivered at the horn output at approximately -130 degrees F.
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Dry ice would be better IMO. Its easier to handle, cheaper and not hard to get at all. Its not quite as cold but much more stable to work with.
 
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What if you just keep the diode in a box with lots of silica gel first? That'd rid the moisture and prevent the frost. Then depending on how you might want to do it, it could be an option to conduct the experiment in that box too.
 
Mariomaster and I both have cryogenic coolers capable of condensing gas to cryogenic temperatures. Its not liquid nitrogen but its close. Mariomaster also has a spectrometer.

Few problems that I see with testing these diodes in cryogenic temps is ice and water collecting inside of the diode and on the window. It would have to be done in an extremely dry environment if you want any chance of not killing/damaging it with moisture.

Cooling the diode from room temp to cryogenic temps may cause the die to crack from thermal contraction. It would most likely crack the window as well.

You could probably do this test for jokes after all the important stuff is done.

Just my 2 cents
 
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jeffreythe00 said:
Mariomaster and I both have cryogenic coolers capable of condensing gas to cryogenic temperatures. Its not liquid nitrogen but its close. Mariomaster also has a spectrometer.

Few problems that I see with testing these diodes in cryogenic temps is ice and water collecting inside of the diode and on the window. It would have to be done in an extremely dry environment if you want any chance of not killing/damaging it with moisture.

Cooling the diode from room temp to cryogenic temps may cause the die to crack from thermal contraction. It would most likely crack the window as well.

You could probably do this test for jokes after all the important stuff is done.

Just my 2 cents
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From what I have seen the best method to prevent damage to the diode due to extreme cooling is to turn the laser on before its cooled down so that it will be producing heat actively which causes it cool more gradually.
 
Thats is one of the coolest things Ive ever seen. It simply gets so cold liquid air drips off.

I need one...

How much did that cost you? Ben krasnow talks about getting them for under $300 on ebay.
 
benmwv said:
Thats is one of the coolest things Ive ever seen. It simply gets so cold liquid air drips off.

I need one...

How much did that cost you? Ben krasnow talks about getting them for under $300 on ebay.
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I dunno about $300, "maybe" but I don't think so. It seems the average going price is around $500-$600 thought you might be able to get them within the $400-$500 range if you are patient enough.

Mine costed 450$ shipping included and I have watched ebay for them routinely for a few months before I found one within my price range.
 
Hi, I feel really bad for saying this but..

If someone does ever run into a "zombie" 520 can they please consider selling it to me as I need a very low power (<5mW) for data recovery.

I tried the experiment with 405nm but it never worked as the lenses on most DVD writers attenuate this far too much.
520nm might barely work and plus the diode should fit inside the existing block on many cheap writers :-)

Thanks!!
-Andre
 
^ I have yet to hear of a zombie PL520, they are pretty hard to kill :p
 
Mine did something weird... At first, and at only an absolute max of 280 mA, it gave 84 mW. After a few days I noticed it wasnt as bright and decided to LPM it again. It only gave a max of 10 ish mW. I reduced the current using the pot on my Xboost and watched the LPM graph. At around 200 mA I got a max of 15 mW and there it stayed...So yes they can be damaged with 280 mA.

The good news is that the wavelength shifted in the process and as it looked more slightly more blueish, I decided to use a diffraction grating to test it. The new wavelength was 510 nm. ;)

The diode is still working fine but now with a reduced output of 15 mW the colour next to my 532 is much bluer though! :) The diode was bought from DTR so it wasnt a problem with the source. :beer:

Edit heres a pic against a 532 - Taken from my fun in the garden thread ;)

42788d1376439211-fun-garden-520-white-light-pic-heavy-garden-pics-2.jpg
 
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Hey grainde,
I still think your "Fun in the Garden" pics are among the best on this forum. So surreal!
 
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