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big problems with sharp 185 mW 638 nm diodes

reloader45

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hello,

I will take a photo, when the tester is finished. I do not use any capacitor in this tester. I also showed pictures of the current from an oscilloscope from such a Driver during power switching on and off in annother thread. The switching is very smooth, no Spikes.
This driver will never kill a Diode that was not dead before.

best regards

Edgar
 



trinh hong phuoc

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hello,

I will take a photo, when the tester is finished. I do not use any capacitor in this tester. I also showed pictures of the current from an oscilloscope from such a Driver during power switching on and off in annother thread. The switching is very smooth, no Spikes.
This driver will never kill a Diode that was not dead before.

best regards

Edgar
sound good, goodluck for your works bros
 

Lifetime17

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Hi, Reloader,
You should try the Mitsu 500 638nm diodes they are very strong and take a beating. Its an open can diode but very robust. And these can do 1W+ easy for a long time, I have several running for years now awesome diodes.
Rich:)
 

paul1598419

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I use transistor sockets with my PS when testing diodes for wavelength. That way I never have to solder to any diode in test. I have some copper cube modules for heat dissipation. They are easy to press diodes into and out of.
 

reloader45

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Hello,

I ordered some Mitsu 500 mA 638 nm from a chinese dealer beginning of this year. After 3 months I got tired of waiting and cancelled my order. The dealer wants a 5 star note from me before he would send the money back. That was the time when I called in Ebay and everthing was fine.

Meanwhile I bought two 700 mA Oclaro diodes. The power oputput is ok, but the beam has a lot of divergence. I don´t like this diode.
Is the beam of the Mitsu more visible?

High Paul, I am thinking about a collet like copper heat sink for diode testing. So I do`nt have to press diodes in and out. When I am sure which construction is ok, I will build one
 

paul1598419

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The Oclaro and the MIts have the same awful divergence. I prefer the Mits because I killed both of my Oclaros years ago, but have never had a problem with the Mitsubishi. They both stink in that you get a long line out instead of a short one or a dot.

I have some round modules that don't need pressing for heat sinking too, when testing diodes without having to solder or press them. It is just easier to use the cube modules as they don't roll.
 

Lifetime17

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Hi
Yes the Oclaro and the Mitsu have the same divergence but the 500 will last forever compared to the Oclaro by a mile
Rich
 

RedCowboy

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I like the Sharp 185mw 638nm very well, it has good divergence, it is single mode but mitsu 500 and oclero 700 are multi mode and have terrible divergence.

Maybe try Sharp 185mw again but avoid static.

Here's one of my sharp 185mw 638nm, I drive @ 300ma and get about a 1/4 watt out.
I also am using an LDSE500 driver, it's a great driver.

65405
 
Last edited:

CDBEAM777

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Hello,

at the Moment I build a laser Diode tester from LM317 IC with 3 current steps from 120 mA to 240 mA.
I will power the tester with a 18350 cell and magnetic contacts.
Power on is made with a push button to run the uncooled Diode only for the split of a second. I am waiting for the IC test socket to connect the laser Diode to my test device. So I am sure, that I will not kill further diodes during function control.

I do not think , that this posting is Entertainment.


best regards

Edgar
Hmmm...I think " Entertaining " was a poor choice of words on my part. More like...." Interesting" to see that others have these unexplained failures at times. I find no entertainment in reading about your frustration....just a " I have been there Too " feeling . Good luck.

CDBEAM
 

reloader45

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Hallo,

I am not frustrated. I only lost money for nothing.

Yes, I will give the sharp diodes a second chance. But I will go to holydays in a week. So I can not order anything from US or China at the moment.
Yesterday, I made my first attempt to anodize aluminum. The result looks good, but now I am waiting for the black dye from Tifoo


best regards

Edgar
 

reloader45

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Hello,

as promised, my first collet 5,6 mm heat sink for dide testing. I use it together with my laser diode test device. The bore is 5,60 mm. The diode can be pressed in with finger force and than the M4 screw will fix the diode in the collet.
So there is no need for pressing the diode and no risk of damaging the diode.

collet heat sink.jpg

with best regards

Edgar
 

paul1598419

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Can't tell if there is a seat for the diode's rim to butt up against. That is necessary to remove heat from the diode because just using the rim's edge is not enough.
 

reloader45

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Dear Paul,

this collet type heat sink is only made for testing diodes. Sso they will only run for seconds. With 250 mA, the heat sink did not even get warm.
I could, of course, build a perfect heat sink, but this device works well for his task.

But I have another question. I could not find how to send a personal message to a member. Any advice is welcome.

best regards

Edgar
 

trinh hong phuoc

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Dear Paul,

this collet type heat sink is only made for testing diodes. Sso they will only run for seconds. With 250 mA, the heat sink did not even get warm.
I could, of course, build a perfect heat sink, but this device works well for his task.

But I have another question. I could not find how to send a personal message to a member. Any advice is welcome.

best regards

Edgar
You only need cilck name of members,then click "start conversation"
 

reloader45

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Hello,

thank you, I was not sure sure if the conversation is public.


best regards

Edgar
 

reloader45

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Hello,

attached you will see a photo of my test device running at 250 mA. It is battery powerd with two 18350 cells.



I took a testr device.JPGused plastic box, so the look is not very nice.

best regards

Edgar
 




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